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Astronomy With An Opera-Glass
By
Garrett P. Serviss
Cont=
ents
CHAPTER
I - THE STARS OF SPRING.
CHAPTER
II - THE STARS OF SUMMER.
CHAPTER
III - THE STARS OF AUTUMN.
CHAPTER
IV - THE STARS OF WINTER.
CHAPTER
V - THE MOON, THE PLANETS, AND THE SUN.
In the
pages that follow, the author has endeavored to encourage the study of the
heavenly bodies by pointing out some of the interesting and marvelous pheno=
mena
of the universe that are visible with little or no assistance from optical
instruments, and indicating means of becoming acquainted with the
constellations and the planets. Knowing that an opera-glass is capable of
revealing some of the most beautiful sights in the starry dome, and believi=
ng
that many persons would be glad to learn the fact, he set to work with such=
an
instrument and surveyed all the constellations visible in the latitude of N=
ew
York, carefully noting everything that it seemed might interest amateur
star-gazers. All the objects thus observed have not been included in this b=
ook,
lest the multiplicity of details should deter or discourage the very readers
for whom it was specially written. On the other hand, there is nothing desc=
ribed
as visible with an opera-glass or a field-glass which the author has not se=
en
with an instrument of that description, and which any person possessing
eye-sight of average quality and a competent glass should not be able to
discern.
But, in order to lend due interest to the subj=
ect,
and place it before the reader in a proper light and true perspective, many
facts have been stated concerning the objects described, the ascertainment =
of
which has required the aid of powerful telescopes, and to observers with su=
ch instruments
is reserved the noble pleasure of confirming with their own eyes those
wonderful discoveries which the looker with an opera-glass can not hope to
behold unless, happily, he should be spurred on to the possession of a
telescope. Yet even to glimpse dimly these distant wonders, knowing what a
closer view would reveal, is a source of no mean satisfaction, while the
celestial phenomena that lie easily within reach of an opera-glass are
sufficient to furnish delight and instruction for many an evening.
It should be said that the division of the sta=
rs
used in this book into the "Stars of Spring," "Stars of
Summer," "Stars of Autumn," and "Stars of Winter,"=
is
purely arbitrary, and intended only to indicate the seasons when certain
constellations are best situated for observation or most conspicuous.
The greater part of the matter composing this
volume appeared originally in a series of articles contributed by the autho=
r to
"The Popular Science Monthly" in 1887-'88. The reception that tho=
se
articles met with encouraged him to revise and enlarge them for publication=
in
the more permanent form of a book.
=
G. P. S.
BROO=
KLYN,
N. Y., September, 1888.
Star-=
gazing
was never more popular than it is now. In every civilized country many
excellent telescopes are owned and used, often to very good purpose, by per=
sons
who are not practical astronomers, but who wish to see for themselves the
marvels of the sky, and who occasionally stumble upon something that is new
even to professional star-gazers. Yet, notwithstanding this activity in the
cultivation of astronomical studies, it is probably safe to assert that har=
dly
one person in a hundred knows the chief stars by name, or can even recognize
the principal constellations, much less distinguish the planets from the fi=
xed
stars. And of course they know nothing of the intellectual pleasure that
accompanies a knowledge of the stars. Modern astronomy is so rapidly and
wonderfully linking the earth and the sun together, with all the orbs of sp=
ace,
in the bonds of close physical relationship, that a person of education and
general intelligence can offer no valid excuse for not knowing where to look
for Sirius or Aldebaran, or the Orion nebula, or the planet Jupiter. As
Australia and New Zealand and the islands of the sea are made a part of the
civilized world through the expanding influence of commerce and cultivation=
, so
the suns and planets around us are, in a certain sense, falling under the d=
ominion
of the restless and resistless mind of man. We have come to possess vested =
intellectual
interests in Mars and Saturn, and in the sun and all his multitude of fello=
ws,
which nobody can afford to ignore.
A singular proof of popular ignorance of the
starry heavens, as well as of popular curiosity concerning any uncommon
celestial phenomenon, is furnished by the curious notions prevailing about =
the
planet Venus. When Venus began to attract general attention in the western =
sky
in the early evenings of the spring of 1887, speculation quickly became rife
about it, particularly on the great Brooklyn Bridge. As the planet hung daz=
zlingly
bright over the New Jersey horizon, some people appeared to think it was the
light of Liberty's torch, mistaking the bronze goddess's real flambeau for a
part of the electric-light system of the metropolis. Finally (to judge from=
the
letters written to the newspapers, and the questions asked of individuals
supposed to know something about the secrets of the sky), the conviction se=
ems
to have become pretty widely distributed that the strange light in the west=
was
no less than an electrically illuminated balloon, nightly sent skyward by M=
r.
Edison, for no other conceivable reason than a wizardly desire to mystify h=
is
fellow-men. I have positive information that this ridiculous notion has been
actually entertained by more than one person of intelligence. And as Venus
glowed with increasing splendor in the serene evenings of June, she continu=
ed
to be mistaken for some petty artificial light instead of the magnificent w=
orld
that she was, sparkling out there in the sunshine like a globe of burnished
silver. Yet Venus as an evening star is not so rare a phenomenon that peopl=
e of
intelligence should be surprised at it. Once in every 584 days she reappear=
s at
the same place in the sunset sky--
&quo=
t;Gem
of the crimson-colored even, Comp=
anion
of retiring day."
No eye can fail to note her, and as the nearest
and most beautiful of the Earth's sisters it would seem that everybody shou=
ld
be as familiar with her appearance as with the face of a friend. But the
popular ignorance of Venus, and the other members of the planetary family t=
o which
our mother, the Earth, belongs, is only an index of the denser ignorance
concerning the stars--the brothers of our great father, the Sun. I believe =
this
ignorance is largely due to mere indifference, which, in its turn, arises f=
rom
a false and pedantic method of presenting astronomy as a creature of
mathematical formulæ, and a humble handmaiden of the art of navigation. I do
not, of course, mean to cast doubt upon the scientific value of technical w=
ork
in astronomy. The science could not exist without it. Those who have made t=
he
spectroscope reveal the composition of the sun and stars, and who are now
making photography picture the heavens as they are, and even reveal phenome=
na which
lie beyond the range of human vision, are the men who have taken astronomy =
out
of its swaddling-clothes, and set it on its feet as a progressive science. =
But
when one sees the depressing and repellent effect that has evidently been
produced upon the popular mind by the ordinary methods of presenting astron=
omy,
one can not resist the temptation to utter a vigorous protest, and to decla=
re
that this glorious science is not the grinning mathematical skeleton that it
has been represented to be.
Perhaps one reason why the average educated ma=
n or
woman knows so little of the starry heavens is because it is popularly supp=
osed
that only the most powerful telescopes and costly instruments of the
observatory are capable of dealing with them. No greater mistake could be m=
ade.
It does not require an optical instrument of any kind, nor much labor, as c=
ompared
with that expended in the acquirement of some polished accomplishments rega=
rded
as indispensable, to give one an acquaintance with the stars and planets wh=
ich
will be not only pleasurable but useful. And with the aid of an opera-glass
most interesting, gratifying, and, in some instances, scientifically valuab=
le
observations may be made in the heavens. I have more than once heard persons
who knew nothing about the stars, and probably cared less, utter exclamatio=
ns
of surprise and delight when persuaded to look at certain parts of the sky =
with
a good glass, and thereafter manifest an interest in astronomy of which they
would formerly have believed themselves incapable.
Being convinced that whoever will survey the
heavens with a good opera-glass will feel repaid many fold for his time and
labor, I have undertaken to point out some of the objects most worthy of
attention, and some of the means of making acquaintance with the stars.
First, a word about the instrument to be used.
Galileo made his famous discoveries with what was, in principle of
construction, simply an opera-glass. This form of telescope was afterward
abandoned because very high magnifying powers could not be employed with it,
and the field of view was restricted. But, on account of its brilliant
illumination of objects looked at, and its convenience of form, the opera-g=
lass
is still a valuable and, in some respects, unrivaled instrument of observat=
ion.
In choosing an opera-glass, see first that the
object-glasses are achromatic, although this caution is hardly necessary, f=
or
all modern opera-glasses, worthy of the name, are made with achromatic
objectives. But there are great differences in the quality of the work. If a
glass shows a colored fringe around a bright object, reject it. Let the dia=
meter
of the object-glasses, which are the large lenses in the end farthest from =
the
eye, be not less than an inch and a half. The magnifying power should be at
least three or four diameters. A familiar way of estimating the magnifying
power is by looking at a brick wall through one barrel of the opera-glass w=
ith
one eye, while the other eye sees the wall without the intervention of the
glass. Then notice how many bricks seen by the naked eye are required to eq=
ual
in thickness one brick seen through the glass. That number represents the
magnifying power.
The instrument used by the writer in making mo=
st
of the observations for this book has object-glasses 1.6 inch in diameter, =
and
a magnifying power of about 3.6 times.
See that the fields of view given by the two
barrels of the opera-glass coincide, or blend perfectly together. If one
appears to partially overlap the other when looking at a distant object, the
effect is very annoying. This fault arises from the barrels of the opera-gl=
ass
being placed too far apart, so that their optical centers do not coincide w=
ith the
centers of the observer's eyes.
Occasionally, on account of faulty centering of
the lenses, a double image is given of objects looked at, as illustrated in=
the
accompanying cut. In such a case the glass is worthless; but if the effect =
is
simply the addition of a small, crescent-shaped extension on one side of th=
e field
of view without any reduplication, the fault may be overlooked, though it is
far better to select a glass that gives a perfectly round field. Some glass=
es
have an arrangement for adjusting the distance between the barrels to suit =
the
eyes of different persons, and it would be well if all were made adjustable=
in
the same way.
Don't buy a cheap glass, but don't waste your
money on fancy mountings. What the Rev. T. W. Webb says of telescopes is
equally true of opera-glasses: "Inferior articles may be showily got u=
p,
and the outside must go for nothing." There are a few makers whose nam=
es,
stamped upon the instrument, may generally be regarded as a guarantee of
excellence. But the best test is that of actual performance. I have a
field-glass which I found in a pawn-shop, that has no maker's name upon it,=
but
in some respects is quite capable of bearing comparison with the work of the
best advertised opticians. And this leads me to say that, by the exercise of
good judgment, one may occasionally purchase superior glasses at very
reasonable prices in the pawn-shops. Ask to be shown the old and well-tried
articles; you may find among them a second-hand glass of fine optical
properties. If the lenses are not injured, one need not trouble one's self
about the worn appearance of the outside of the instrument; so much the more
evidence that somebody has found it well worth using.
A good field or marine glass is in some respec=
ts
better than an opera-glass for celestial observations. It possesses a much
higher magnifying power, and this gives sometimes a decided advantage. But,=
on the
other hand, its field of view is smaller, rendering it more difficult to fi=
nd
and hold objects. Besides, it does not present as brilliant views of scatte=
red
star-clusters as an opera-glass does. For the benefit of those who possess
field-glasses, however, I have included in this brief survey certain objects
that lie just beyond the reach of opera-glasses, but can be seen with the
larger instruments.
I have thought it advisable in the description=
s of
the constellations which follow to give some account of their mythological
origin, both because of the historical interest which attaches to it, and
because, while astronomers have long since banished the constellation figur=
es from
their maps, the names which the constellations continue to bear require some
explanation, and they possess a literary and romantic interest which can no=
t be
altogether disregarded in a work that is not intended for purely scientific=
readers.
Having
selected your glass, the next thing is to find the stars. Of course, one co=
uld
sweep over the heavens at random on a starry night and see many interesting
things, but he would soon tire of such aimless occupation. The observer must
know what he is looking at in order to derive any real pleasure or satisfac=
tion
from the sight.
It really makes no difference at what time of =
the
year such observations are begun, but for convenience I will suppose that t=
hey are
begun in the spring. We can then follow the revolution of the heavens throu=
gh a
year, at the end of which the diligent observer will have acquired a compet=
ent knowledge
of the constellations. The circular map, No. 1, represents the appearance of
the heavens at midnight on the 1st of March, at eleven o'clock on the 15th =
of
March, at ten o'clock on the 1st of April, at nine o'clock on the 15th of
April, and at eight o'clock on the 1st of May. The reason why a single map =
can
thus be made to show the places of the stars at different hours in different
months will be plain upon a little reflection. In consequence of the earth's
annual journey around the sun, the whole heavens make one apparent revoluti=
on
in a year. This revolution, it is clear, must be at the rate of 30° in a mo=
nth,
since the complete circuit comprises 360°. But, in addition to the annual r=
evolution,
there is a diurnal revolution of the heavens which is caused by the earth's
daily rotation upon its axis, and this revolution must, for a similar reaso=
n,
be performed at the rate of 15° for each of the twenty-four hours. It follo=
ws
that in two hours of the daily revolution the stars will change their place=
s to
the same extent as in one month of the annual revolution. It follows also t=
hat,
if one could watch the heavens throughout the whole twenty-four hours, and =
not
be interrupted by daylight, he would behold the complete circuit of the sta=
rs
just as he would do if, for a year, he should look at the heavens at a part=
icular
hour every night. Suppose that at nine o'clock on the 1st of June we see the
star Spica on the meridian; in consequence of the rotation of the earth, two
hours later, or at eleven o'clock, Spica will be 30° west of the meridian. =
But
that is just the position which Spica would occupy at nine o'clock on the 1=
st
of July, for in one month (supposing a month to be accurately the twelfth p=
art
of a year) the stars shift their places 30° toward the west. If, then, we
should make a map of the stars for nine o'clock on the 1st of July, it would
answer just as well for eleven o'clock on the 1st of June, or for seven o'c=
lock
on the 1st of August.
The center of the map is the zenith, or point
overhead. The reader must now exercise his imagination a little, for it is
impossible to represent the true appearance of the concave of the heavens on
flat paper. Holding the map over your head, with the points marked East, We=
st,
North, and South in their proper places, conceive of it as shaped like the
inside of an open umbrella, the edge all around extending clear down to the=
horizon.
Suppose you are facing the south, then you will see, up near the zenith, the
constellation of Leo, which can be readily recognized on the map by six sta=
rs
that mark out the figure of a sickle standing upright on its handle. The la=
rge
star in the bottom of the handle is Regulus. Having fixed the appearance and
situation of this constellation in your mind, go out-of-doors, face the sou=
th,
and try to find the constellation in the sky. With a little application you
will be sure to succeed.
Using Leo as a basis of operations, your conqu=
est
of the sky will now proceed more rapidly. By reference to the map you will =
be
able to recognize the twin stars of Gemini, southwest of the zenith and high
up; the brilliant lone star, Procyon, south of Gemini; the dazzling Sirius,=
flashing
low down in the southwest; Orion, with all his brilliants, blazing in the w=
est;
red Aldebaran and the Pleiades off to his right; and Capella, bright as a
diamond, high up above Orion, toward the north. In the southeast you will
recognize the quadrilateral of Corvus, with the remarkably white star Spica
glittering east of it.
Next face the north. If you are not just sure
where north is, try a pocket-compass. This advice is by no means unnecessar=
y,
for there are many intelligent persons who are unable to indicate true north
within many degrees, though standing on their own doorstep. Having found th=
e north
point as near as you can, look upward about forty degrees from the horizon,=
and
you will see the lone twinkler called the north or pole star. Forty degrees=
is
a little less than half-way from the horizon to the zenith.
By the aid of the map, again, you will be able=
to
find, high up in the northeast, near the zenith, the large dipper-shaped fi=
gure
in Ursa Major, and, when you have once noticed that the two stars in the ou=
ter edge
of the bowl of the Dipper point almost directly to the pole-star, you will =
have
an unfailing means of picking out the latter star hereafter, when in doubt.=
[A]
Continuing the curve of the Dipper-handle, in the northeast, your eye will =
be
led to a bright reddish star, which is Arcturus, in the constellation Boöte=
s.
[A=
] Let
the reader remember that the distance between the two stars in the brim of the bowl of =
the
Dipper is about ten degrees=
, and
he will have a measuring-stick that he can apply in estimating other distanc=
es in
the heavens.
In the same way you will be able to find the
constellations Cassiopeia, Cepheus, Draco, and Perseus. Don't expect to
accomplish it all in an hour. You may have to devote two or three evenings =
to
such observation, and make many trips indoors to consult the map, before you
have mastered the subject; but when you have done it you will feel amply re=
paid
for your exertions, and you will have made for yourself silent friends in t=
he
heavens that will beam kindly upon you, like old neighbors, on whatever sid=
e of
the world you may wander.
Having fixed the general outlines and location=
of
the constellations in your mind, and learned to recognize the chief stars, =
take
your opera-glass and begin with the constellation Leo and the star Regulus.=
Contrive
to have some convenient rest for your arms in holding the glass, and thus
obtain not only comfort but steadiness of vision. A lazy-back chair makes a
capital observing-seat. Be very particular, too, to get a sharp focus. Reme=
mber
that no two persons' eyes are alike, and that even the eyes of the same
observer occasionally require a change. In looking for a difficult object, I
have sometimes suddenly brought the sought-for phenomenon into view by a sl=
ight
turn of the focusing-screw.
You will at once be gratified by the increased
brilliancy of the star as seen by the glass. If the night is clear, it will
glow like a diamond. Yet Regulus, although ranked as a first-magnitude star,
and of great repute among the ancient astrologers, is far inferior in
brilliancy to such stars as Capella and Arcturus, to say nothing of Sirius.=
By consulting map No. 2 you will next be able =
to
find the celebrated star bearing the name of the Greek letter Gamma ([gamma=
]).
If you had a telescope, you would see this star as a close and beautiful
double, of contrasted colors. But it is optically double, even with an
opera-glass. You can not fail to see a small star near it, looking quite cl=
ose
if the magnifying power of your glass is less than three times. You will be=
struck
by the surprising change of color in turning from Regulus to Gamma--the for=
mer
is white and the latter deep yellow. It will be well to look first at one a=
nd
then at the other, several times, for this is a good instance of what you w=
ill
meet with many times in your future surveys of the heavens--a striking cont=
rast
of color in neighboring stars. One can thus comprehend that there is more t=
han
one sense in which to understand the Scriptural declaration that "one =
star
differeth from another in glory." The radiant point of the famous Nove=
mber
meteors, which, in 1833 and 1866, filled the sky with fiery showers, is near
Gamma. Turn next to the star in Leo marked Zeta ([zeta]). If your glass is a
pretty large and good one, and your eye keen, you will easily see three min=
ute
companion stars keeping company with Zeta, two on the southeast, and one, m=
uch
closer, toward the north. The nearest of the two on the south is faint, bei=
ng
only between the eighth and ninth magnitude, and will probably severely test
your powers of vision. Next look at Epsilon ([epsilon]), and you will find =
near
it two seventh-magnitude companions, making a beautiful little triangle.
Away at the eastern end of the constellation, =
in
the tail of the imaginary Lion, upon whose breast shines Regulus, is the st=
ar
Beta ([beta]) Leonis, also called Denebola. It is almost as bright as its l=
eader,
Regulus, and you will probably be able to catch a tinge of blue in its rays.
South of Denebola, at a distance of nineteen minutes of arc, or somewhat mo=
re
than half the apparent diameter of the moon, you will see a little star of =
the
sixth magnitude, which is one of the several "companions" for whi=
ch
Denebola is celebrated. There is another star of the eighth magnitude in the
same direction from Denebola, but at a distance of less than five minutes, =
and
this you may be able to glimpse with a powerful field-glass, under favorable
conditions. I have seen it well with a field-glass of 1.6-inch aperture, an=
d a
magnifying power of seven times. But it requires an experienced eye and ste=
ady vision
to catch this shy twinkler.
When looking for a faint and difficult object,=
the
plan pursued by telescopists is to avert the eye from the precise point upon
which the attention is fixed, in order to bring a more sensitive part of th=
e retina
into play than that usually employed. Look toward the edge of the field of
view, while the object you are seeking is in the center, and then, if it ca=
n be
seen at all with your glass, you will catch sight of it, as it were, out of=
the
corner of your eye. The effect of seeing a faint star in this way, in the
neighborhood of a large one, whose rays hide it from direct vision, is
sometimes very amusing. The little star seems to dart out into view as thro=
ugh
a curtain, perfectly distinct, though as immeasurably minute as the point o=
f a
needle. But the instant you direct your eyes straight at it, presto! it is
gone. And so it will dodge in and out of sight as often as you turn your ey=
es.
If you will sweep carefully over the whole ext=
ent
of Leo, whose chief stars are marked with their Greek-letter names on our
little map, you will be impressed with the power of your glass to bring into
sight many faint stars in regions that seem barren to the naked eye. An
opera-glass of 1.5 aperture will show ten times as many stars as the naked =
eye
can see.
A word about the "Lion" which this
constellation is supposed to represent. It requires a vivid imagination to =
perceive
the outlines of the celestial king of beasts among the stars, and yet someb=
ody
taught the people of ancient India and the old Egyptians to see him there, =
and there
he has remained since the dawn of history. Modern astronomers strike him ou=
t of
their charts, together with all the picturesque multitude of beasts and bir=
ds
and men and women that bear him company, but they can not altogether banish
him, or any of his congeners, for the old names, and, practically, the old
outlines of the constellations are retained, and always will be retained. T=
he
Lion is the most conspicuous figure in the celebrated zodiac of Dendera; an=
d,
indeed, there is evidence that before the story of Hercules and his labors =
was
told this lion was already imagined shining among the stars. It was
characteristic of the Greeks that they seized him for their own, and tried =
to
rob him of his real antiquity by pretending that Jupiter had placed him amo=
ng the
stars in commemoration of Hercules's victory over the Nemæan lion. In the
Hebrew zodiac Leo represented the Lion of Judah. It was thus always a lion =
that
the ancients thought they saw in this constellation.
In the old star-maps the Lion is represented a=
s in
the act of springing upon his prey. His face is to the west, and the star R=
egulus
is in his heart. The sickle-shaped figure covers his breast and head, Gamma
being in the shoulder, Zeta in the mane of the neck, Mu and Epsilon in the =
cheek,
and Lambda in the jaws. The fore-paws are drawn up to the breast and
represented by the stars Zi and Omicron. Denebola is in the tuft of the tai=
l.
The hind-legs are extended downward at full length, in the act of springing.
Starting from the star Delta in the hip, the row consisting of Theta, Iota,
Tau, and Upsilon, shows the line of the hind-legs.
Leo had an unsavory reputation among the ancie=
nts
because of his supposed influence upon the weather. The greatest heat of su=
mmer
was felt when the sun was in this constellation:
&quo=
t;Most
scorching is the chariot of the Sun, And waving spikes no longer hide the fu=
rrows When he begins to travel with the Lion.=
"
Looking now westwardly from the Sickle of Leo,=
at
a distance about equal to twice the length of the Sickle, your eye will be
caught by a small silvery spot in the sky lying nearly between two rather f=
aint
stars. This is the famous Præsepe, or Manger, in the center of the constell=
ation
Cancer. The two stars on either side of it are called the Aselli, or the As=
s's
Colts, and the imagination of the ancients pictured them feeding from their
silver manger. Turn your glass upon the Manger and you will see that it
consists of a crowd of little stars, so small and numerous that you will
probably not undertake to count them, unless you are using a large field-gl=
ass.
Galileo has left a delightful description of his surprise and gratification
when he aimed his telescope at this curious cluster and other similar
aggregations of stars and discovered what they really were. Using his best
instrument, he was able to count thirty-six stars in the Manger. The Manger=
was
a famous weather-sign in olden times, and Aratus, in his "Diosemia,&qu=
ot; advises
his readers to--
&quo=
t;...
watch the Manger: like a little mist Far north in Cancer's territory it floa=
ts. Its confines are two faintly glimmering
stars; These are two asses that a
manger parts, Which suddenly, whe=
n all
the sky is clear, Sometimes quite
vanishes, and the two stars Seem =
to
have closer moved their sundered orbs. No feeble tempest then will soak the le=
as; A murky manger with both stars Shining unaltered is a sign of rain.&qu=
ot;
Like other old weather-saws, this probably
possesses a gleam of sense, for it is only when the atmosphere is perfectly
transparent that the Manger can be clearly seen; when the air is thick with
mist, the harbinger of coming storm, it fades from sight.
The constellation Cancer, or the Crab, was
represented by the Egyptians under the figure of a scarabæus. The observer =
will
probably think that it is as easy to see a beetle as a crab there. Cancer, =
like
Leo, is one of the twelve constellations of the Zodiac, the name applied to=
the
imaginary zone 16° degrees wide and extending completely around the heavens,
the center of which is the ecliptic or annual path of the sun. The names of
these zodiacal constellations, in their order, beginning at the west and
counting round the circle, are: Aries, Taurus, Gemini, Cancer, Leo, Virgo,
Libra, Scorpio, Sagittarius, Capricornus, Aquarius, and Pisces. Cancer has
given its name to the circle called the Tropic of Cancer, which indicates t=
he
greatest northerly declination of the sun in summer, and which he attains on
the 21st or 22d of June. But, in consequence of the precession of the
equinoxes, all of the zodiacal constellations are continually shifting towa=
rd
the east, and Cancer has passed away from the place of the summer solstice,
which is now to be found in Gemini.
Below the Manger, a little way toward the sout=
h,
your eye will be caught by a group of four or five stars of about the same
brightness as the Aselli. This marks the head of Hydra, and the glass will =
show
a striking and beautiful geometrical arrangement of the stars composing it.
Hydra is a very long constellation, and trending southward and eastward fro=
m the
head it passes underneath Leo, and, sweeping pretty close down to the horiz=
on,
winds away under Corvus, the tail reaching to the eastern horizon. The leng=
th
of this skyey serpent is about 100°. Its stars are all faint, except Alphar=
d,
or the Hydra's Heart, a second-magnitude star, remarkable for its lonely
situation, southwest of Regulus. A line from Gamma Leonis through Regulus
points it out. It is worth looking at with the glass on account of its rich
orange-tint.
Hydra is fabled to be the hundred-headed monst=
er
that was slain by Hercules. It must be confessed that there is nothing very
monstrous about it now except its length. The most timid can look upon it
without suspecting its grisly origin.
Coming back to the Manger as a starting-point,
look well up to the north and west, and at a distance somewhat less than th=
at
between Regulus and the Manger you will see a pair of first-magnitude stars,
which you will hardly need to be informed are the celebrated Twins, from wh=
ich
the constellation Gemini takes its name. The star marked [alpha] in the map=
is
Castor, and the star marked [beta] is Pollux. No classical reader needs to =
be
reminded of the romantic origin of these names.
A sharp contrast in the color of Castor and Po=
llux
comes out as soon as the glass is turned upon them. Castor is white, with
occasionally, perhaps, a suspicion of a green ray in its light. Pollux is d=
eep
yellow. Castor is a celebrated double star, but its components are far too
close to be separated with an opera-glass, or even the most powerful field-=
glass.
You will be at once interested by the singular cortége of small stars by wh=
ich
both Castor and Pollux are surrounded. These little attendant stars, for su=
ch
they seem, are arrayed in symmetrical groups--pairs, triangles, and other
figures--which, it seems difficult to believe, could be unintentional, alth=
ough
it would be still more difficult to suggest any reason why they should be
arranged in that way.
Our map will show you the position of the principal stars of the constellation. Castor and Pollux are in the heads of= the Twins, while the row of stars shown in the map Xi ([xi]), Gamma ([gamma]), = Nu ([nu]), Mu ([mu]), and Eta ([eta]), marks their feet, which are dipped in t= he edge of the Milky-Way. One can spend a profitable and pleasurable half-hour in exploring the wonders of Gemini. The whole constellation, from head to foot= , is gemmed with stars which escape the naked eye, but it sparkles like a bead-spangled garment when viewed with the glass. Owing to the presence of = the Milky-Way, the spectacle around the feet of the Twins is particularly magnificent. And here the possessor of a good opera-glass can get a fine vi= ew of a celebrated star-cluster known in the catalogues as 35 M. It is situate= d a little distance northwest of the star Eta, and is visible to the naked eye,= on a clear, moonless night, as a nebulous speck. With a good glass you will see two wonderful streams of little stars starting, one from Eta and the other = from Mu, and running parallel toward the northwest; 35 M is situated between the= se star-streams. The stars in the cluster are so closely aggregated that you w= ill be able to clearly separate only the outlying ones. The general aspect is l= ike that of a piece of frosted silver over which a twinkling light is playing. A field-glass brings out more of the component stars. The splendor of this st= arry congregation, viewed with a powerful telescope, may be guessed at from Admi= ral Smyth's picturesque description: "It presents a gorgeous field of star= s, from the ninth to the sixteenth magnitude, but with the center of the mass = less rich than the rest. From the small stars being inclined to form curves of t= hree or four, and often with a large one at the root of the curve, it somewhat r= eminds one of the bursting of a sky-rocket." And Webb adds that there is an "elegant festoon near the center, starting with a reddish star."<= o:p>
No one can gaze upon this marvelous phenomenon,
even with the comparatively low powers of an opera-glass, and reflect that =
all
these swarming dots of light are really suns, without a stunning sense of t=
he immensity
of the material universe.
It is an interesting fact that the summer
solstice, or the point which the sun occupies when it attains its greatest
northerly declination, on the longest day of the year, is close by this gre=
at
cluster in Gemini. In the glare of the sunshine those swarming stars are th=
en
concealed from our sight, but with the mind's eye we can look past and beyo=
nd
our sun, across the incomprehensible chasm of space, and behold them still =
shining,
their commingled rays making our great God of Day seem but a lonely wandere=
r in
the expanse of the universe.
It was only a short distance southwest of this
cluster that one of the most celebrated discoveries in astronomy was made.
There, on the evening of March 13, 1781, William Herschel observed a star w=
hose
singular aspect led him to put a higher magnifying power on his telescope. =
The higher
power showed that the object was not a star but a planet, or a comet, as
Herschel at first supposed. It was the planet Uranus, whose discovery "=
;at
one stroke doubled the breadth of the sun's dominions."
The constellation of Gemini, as the names of i=
ts
two chief stars indicate, had its origin in the classic story of the twin s=
ons
of Jupiter and Leda:
&quo=
t;Fair
Leda's twins, in time to stars decreed, One fought on foot, one curbed the fiery
steed."
Castor and Pollux were regarded by both the Gr=
eeks
and the Romans as the patrons of navigation, and this fact crops out very
curiously in the adventures of St. Paul. After his disastrous shipwreck on =
the
island of Melita he embarked again on a more prosperous voyage in a ship
bearing the name of these very brothers. "And after three months,"
writes the celebrated apostle (Acts xxviii, 11) "we departed in a ship=
of Alexandria,
which had wintered in the isle, whose sign was Castor and Pollux." We =
may
be certain that Paul was acquainted with the constellation of Gemini, not o=
nly
because he was skilled in the learning of his times, but because, in his sp=
eech
on Mars Hill, he quoted a line from the opening stanzas of Aratus's
"Phenomena," a poem in which the constellations are described.
The map will enable you next to find Procyon, =
or
the Little Dog-Star, more than twenty degrees south of Castor and Pollux, a=
nd
almost directly below the Manger. This star will interest you by its
golden-yellow color and its brightness, although it is far inferior in the
latter respect to Sirius, or the Great Dog-Star, which you will see flashing
splendidly far down beneath Procyon in the southwest. About four degrees
northwest of Procyon is a third-magnitude star, called Gomelza, and the gla=
ss
will show you two small stars which make a right-angled triangle with it, t=
he nearer
one being remarkable for its ruddy color.
Procyon is especially interesting because it is
attended by an invisible star, which, while it has escaped all efforts to
detect it with powerful telescopes, nevertheless reveals its presence by the
effect of its attraction upon Procyon. It is a curious fact that both of the
so-called Dog-Stars are thus attended by obscure or dusky companion-stars,
which, notwithstanding their lack of luminosity, are of great magnitude. In=
the
case of Sirius, the improvement in telescopes has brought the mysterious at=
tendant
into view, but Procyon's mate remains hidden from our eyes. But it can not
escape the ken of the mathematician, whose penetrating mental vision has, in
more than one instance, outstripped the discoveries of the telescope. Almost
half a century ago the famous Bessel announced his conclusion--in the light=
of
later developments it may well be called discovery--that both Sirius and
Procyon were binary systems, consisting each of a visible and an invisible
star. He calculated the probable period of revolution, and found it to be, =
in each
case, approximately fifty years. Sixteen years after Bessel's death, one of
Alvan Clark's unrivaled telescopes at last revealed the strange companion of
Sirius, a huge body, half as massive as the giant Dog-Star itself, but ten
thousand times less brilliant, and more recent observations have shown that=
its
period of revolution is within six or seven months of the fifty years assig=
ned
by Bessel. If some of the enormous telescopes that have been constructed in=
the
past few years should succeed in rendering Procyon's companion visible also=
, it
is highly probable that Bessel's prediction would receive another substanti=
al
fulfillment.
The mythological history of Canis Minor is
somewhat obscure. According to various accounts it represents one of Diana's
hunting-dogs, one of Orion's hounds, the Egyptian dog-headed god Anubis, and
one of the dogs that devoured their master Actæon after Diana had turned him
into a stag. The mystical Dr. Seiss leaves all the ancient myth-makers far =
in the
rear, and advances a very curious theory of his own about this constellatio=
n,
in his "Gospel in the Stars," which is worth quoting as an exampl=
e of
the grotesque fancies that even in our day sometimes possess the minds of m=
en
when they venture beyond the safe confines of this terraqueous globe. After
summarizing the various myths we have mentioned, he proceeds to identify
Procyon, putting the name of the chief star for the constellation, "as=
the
starry symbol of those heavenly armies which came forth along with the King=
of
kings and Lord of lords to the battle of the great day of God Almighty, to =
make
an end of misrule and usurpation on earth, and clear it of all the wild bea=
sts which
have been devastating it for these many ages."
The reader will wonder all the more at this
rhapsody after he has succeeded in picking out the modest Little Dog in the
sky.
Sirius, Orion, Aldebaran, and the Pleiades, al=
l of
which you will perceive in the west and southwest, are generally too much
involved in the mists of the horizon to be seen to the best advantage at th=
is season,
although it will pay you to take a look through the glass at Sirius. But the
splendid star Capella, in the constellation Auriga, may claim a moment's
attention. You will find it high up in the northwest, half-way between Orion
and the pole-star, and to the right of the Twins. It has no rival near, and=
its
creamy-white light makes it one of the most beautiful as well as one of the
most brilliant stars in the heavens. Its constitution, as revealed by the
spectroscope, resembles that of our sun, but the sun would make but a sorry
figure if removed to the side of this giant star. About seven and a half
degrees above Capella, and a little to the left, you will see a
second-magnitude star called Menkalina. Two and a half times as far to the
left, or south, in the direction of Orion, is another star of equal brightn=
ess
to Menkalina. This is El Nath, and marks the place where the foot of Auriga=
, or
the Charioteer, rests upon the point of the horn of Taurus. Capella, Menkal=
ina,
and El Nath make a long triangle which covers the central part of Auriga. T=
he
naked eye shows two or three misty-looking spots within this triangle, one =
to
the right of El Nath, one in the upper or eastern part of the constellation,
near the third-magnitude star Theta ([theta]), and another on a line drawn =
from
Capella to El Nath, but much nearer to Capella. Turn your glass upon these
spots, and you will be delighted by the beauty of the little stars to whose
united rays they are due.
El Nath has around it some very remarkable row=
s of
small stars, and the whole constellation of Auriga, like that of Gemini,
glitters with star-dust, for the Milky-Way runs directly through it.
With a powerful field-glass you may try a glim=
pse
at the rich star-clusters marked 38 M, 37 M, and 33^7.
The mythology of Auriga is not clear, but the
ancients seem to have been of one mind in regarding the constellation as
representing the figure of a man carrying a goat and her two kids in his ar=
ms.
Auriga was also looked upon as a beneficent constellation, and the goat and
kids were believed to be on the watch to rescue shipwrecked sailors. As
Capella, which represents the fabled goat, shines nearly overhead in winter,
and would ordinarily be the first bright star to beam down through the brea=
king
clouds of a storm at that season, it is not difficult to imagine how it got=
its
reputation as the seaman's friend. Dr. Seiss has so spirited a description =
of
the imaginary figure contained in this constellation that I can not refrain
from quoting it:
"The figure itself is that of a mighty man
seated on the Milky-Way, holding a band or ribbon in his right hand, and wi=
th
his left arm holding up on his shoulder a she-goat which clings to his neck=
and
looks out in astonishment upon the terrible bull; while in his lap are two =
frightened
little kids which he supports with his great hand."
It is scarcely necessary to add that Dr. Seiss
insists that Auriga, as a constellation, was invented long before the time =
of
the Greeks, and was intended prophetically to represent that Good Shepherd =
who
was to come and rescue the sinful world.
If any reader wishes to exercise his fancy by
trying to trace the outlines of this figure, he will find the head of Auriga
marked by the star Delta ([delta]) and the little group near it. Capella, in
the heart of the Goat, is just below his left shoulder, and Menkalina marks=
his
right shoulder. El Nath is in his right foot, and Iota ([iota]) in his left
foot. The stars Epsilon ([epsilon]), Zeta ([zeta]), Eta ([eta]), and Lambda
([lambda]) shine in the kids which lie in Auriga's lap. The faint stars
scattered over the eastern part of the constellation are sometimes represen=
ted
as forming a whip with many lashes, which the giant flourishes with his rig=
ht
hand.
Let us turn back to Denebola in the Lion's Tai=
l.
Now glance from it down into the southeast, and you will see a brilliant st=
ar
flashing well above the horizon. This is Spica, the chief twinkler of Virgo,
and it is marked on our circular map. Then look into the northwest, and at
about the same distance from Denebola, but higher above the horizon than Sp=
ica,
you will catch the sparkling of a large, reddish star. It is Arcturus in
Boötes. The three, Denebola, Spica, and Arcturus, mark the corners of a gre=
at
equilateral triangle. Nearly on a line between Denebola and Arcturus, and
somewhat nearer to the former, you will perceive a curious twinkling, as if
gossamers spangled with dew-drops were entangled there. One might think the=
old
woman of the nursery rhyme who went to sweep the cobwebs out of the sky had
skipped this corner, or else that its delicate beauty had preserved it even
from her housewifely instincts. This is the little constellation called
Berenice's Hair. Your opera-glass will enable you to count twenty or thirty=
of
the largest stars composing this cluster, which are arranged, as so often
happens, with a striking appearance of geometrical design. The constellation
has a very romantic history. It is related that the young Queen Berenice, w=
hen
her husband was called away to the wars, vowed to sacrifice her beautiful
tresses to Venus if he returned victorious over his enemies. He did return =
home
in triumph, and Berenice, true to her vow, cut off her hair and bore it to =
the
Temple of Venus. But the same night it disappeared. The king was furious, a=
nd
the queen wept bitterly over the loss. There is no telling what might have
happened to the guardians of the temple, had not a celebrated astronomer na=
med
Conon led the young king and queen aside in the evening and showed them the
missing locks shining transfigured in the sky. He assured them that Venus h=
ad placed
Berenice's lustrous ringlets among the stars, and, as they were not skilled=
in
celestial lore, they were quite ready to believe that the silvery swarm they
saw near Arcturus had never been there before. And so for centuries the wor=
ld
has recognized the constellation of Berenice's Hair.
Look next at Corvus and Crater, the Crow and t=
he
Cup, two little constellations which you will discover on the circular map,=
and
of which we give a separate representation in Map 5. You will find that the
stars Delta ([delta]) and Eta ([eta]), in the upper left-hand corner of the=
quadrilateral
figure of Corvus, make a striking appearance. The little star Zeta ([zeta])=
is
a very pretty double for an opera-glass. There is a very faint pair of stars
close below and to the right of Beta ([beta]). This forms a severe test. On=
ly a
good opera-glass will show these two stars as a single faint point of light=
. A
field-glass, however, will show both, one being considerably fainter than t=
he
other. Crater is worth sweeping over for the pretty combinations of stars t=
o be
found in it.
You will observe that the interminable Hydra
extends his lengthening coils along under both of the constellations. In fa=
ct,
both the Cup and the Crow are represented as standing upon the huge serpent.
The outlines of a cup are tolerably well indicated by the stars included un=
der
the name Crater, but the constellation of the Crow might as well have borne=
any
other name so far as any traceable likeness is concerned. One of the legends
concerning Corvus avers that it is the daughter of the King of Phocis, who =
was
transformed into a crow to escape the pursuit of Neptune. She is certainly =
safe
in her present guise.
Arcturus and Spica, and their companions, may =
be
left for observation to a more convenient season, when, having risen higher,
they can be studied to better advantage. It will be well, however, to merely
glance at them with the glass in order to note the great difference of
color--Spica being brilliantly white and Arcturus almost red.
We will now turn to the north. You have already
been told how to find the pole-star. Look at it with your glass. The pole-s=
tar
is a famous double, but its minute companion can only be seen with a telesc=
ope.
As so often happens, however, it has another companion for the opera-glass,=
and
this latter is sufficiently close and small to make an interesting test for=
an
inexperienced observer armed with a glass of small power. It must be looked=
for
pretty close to the rays of the large star, with such a glass. It is of the
seventh magnitude. With a large field-glass several smaller companions may =
be
seen, and a very excellent glass may show an 8.5-magnitude star almost hidd=
en
in the rays of the seventh-magnitude companion.
With the aid of map No. 6 find in Ursa Minor,
which is the constellation to which the pole-star belongs, the star Beta
([beta]), which is also called Kochab (the star marked [alpha] in the map is
the pole-star). Kochab has a pair of faint stars nearly north of it, about =
one
degree distant. With a small glass these may appear as a single star, but a
stronger glass will show them separately.
And now for Ursa Major and the Great
Dipper--Draco, Cepheus, Cassiopeia, and the other constellations represente=
d on
the circular map, being rather too near the horizon for effective observati=
on
at this time of the year. First, as the easiest object, look at the star in=
the
middle of the handle of the Dipper (this handle forms the tail of Ursa Majo=
r), and
a little attention will show you, without the aid of a glass, if your eye-s=
ight
is good, that the star is double. A smaller star seems to be almost in cont=
act
with it. The larger of these two stars is called Mizar and the smaller
Alcor--the Horse and his Rider the Arabs said. Your glass will, of course,
greatly increase the distance between Alcor and Mizar, and will also bring =
out
a clear difference of color distinguishing them. Now, if you have a very
powerful glass, you may be able to see the Sidus Ludovicianum, a minute star
which a German astronomer discovered more than a hundred and fifty years ag=
o,
and, strangely enough, taking it for a planet, named it after a German prin=
ce.
The position of the Sidus Ludovicianum, with reference to Mizar and Alcor, =
is
represented in the accompanying sketch. You must look very sharply if you
expect to see it, and your opera-glass will have to be a large and strong o=
ne.
A field-glass, however, can not fail to show it.
Sweep along the whole length of the Dipper's
handle, and you will discover many fine fields of stars. Then look at the s=
tar
Alpha ([alpha]) in the outer edge of the bowl nearest to the pole-star. The=
re is
a faint star, of about the eighth magnitude, near it, in the direction of B=
eta
([beta]). This will prove a very difficult test. You will have to try it wi=
th
averted vision. If you have a field-glass, catch it first with that, and,
having thus fixed its position in your mind, try to find it with the
opera-glass. Its distance is a little over half that between Mizar and Alco=
r.
It is of a reddish color.
You will notice nearly overhead three pairs of
pretty bright stars in a long, bending row, about half-way between Leo and =
the
Dipper. These mark three of Ursa Major's feet, and each of the pairs is well
worth looking at with a glass, as they are beautifully grouped with stars
invisible to the naked eye. The letters used to designate the stars forming
these pairs will be found upon our map of Ursa Major. The scattered group o=
f faint
stars beyond the bowl of the Dipper forms the Bear's head, and you will find
that also a field worth a few minutes' exploration.
The two bears, Ursa Major and Ursa Minor, swin=
ging
around the pole of the heavens, have been conspicuous in the star-lore of a=
ll
ages. According to fable, they represent the nymph Calisto, with whom Jupit=
er was
in love, and her son Arcas, who were both turned into bears by Juno, whereu=
pon
Jupiter, being unable to restore their form, did the next best thing he cou=
ld
by placing them among the stars. Ursa Major is Calisto, or Helica, as the
Greeks called the constellation. The Greek name of Ursa Minor was Cynosura.=
The
use of the pole-star in navigation dates back at least to the time of the
Phoenicians. The observer will note the uncomfortable position of Ursa Mino=
r,
attached to the pole by the end of its long tail.
But, after all, no one can expect to derive fr=
om
such studies as these any genuine pleasure or satisfaction unless he is min=
dful
of the real meaning of what he sees. The actual truth seems almost too
stupendous for belief. The mind must be brought into an attitude of profoun=
d contemplation
in order to appreciate it. From this globe we can look out in every directi=
on
into the open and boundless universe. Blinded and dazzled during the day by=
the
blaze of that star, of which the earth is a near and humble dependent, we a=
re shut
in as by a curtain. But at night, when our own star is hidden, our vision
ranges into the depths of creation, and we behold them sparkling with a
multitude of other suns. With so simple an aid as that of an opera-glass we
penetrate still deeper into the profundities of space, and thousands more of
these strange, far-away suns come into sight. They are arranged in pairs, s=
ets,
rows, streams, clusters--here they gleam alone in distant splendor, there t=
hey
glow and flash in mighty swarms. This is a look into heaven more splendid t=
han
the imagination of Bunyan pictured; here is a celestial city whose temples =
are
suns, and whose streets are the pathways of light.
Let u=
s now
suppose that the Earth has advanced for three months in its orbit since we
studied the stars of spring, and that, in consequence, the heavens have made
one quarter of an apparent revolution. Then we shall find that the stars wh=
ich
in spring shone above the western horizon have been carried down out of sig=
ht,
while the constellations that were then in the east have now climbed to the
zenith, or passed over to the west, and a fresh set of stars has taken their
place in the east. In the present chapter we shall deal with what may be ca=
lled
the stars of summer; and, in order to furnish occupation for the observer w=
ith
an opera-glass throughout the summer months, I have endeavored to so choose=
the
constellations in which our explorations will be made, that some of them sh=
all
be favorably situated in each of the months of June, July, and August. The
circular map represents the heavens at midnight on the 1st of June; at elev=
en
o'clock, on the 15th of June; at ten o'clock, on the 1st of July; at nine
o'clock, on the 15th of July; and at eight o'clock, on the 1st of August.
Remembering that the center of the map is the point over his head, and that=
the
edge of it represents the circle of the horizon, the reader, by a little
attention and comparison with the sky, will be able to fix in his mind the =
relative
situation of the various constellations. The maps that follow will show him
these constellations on a larger scale, and give him the names of their chi=
ef
stars.
The observer need not wait until midnight on t=
he
1st of June in order to find some of the constellations included in our map.
Earlier in the evening, at about that date, say at nine o'clock, he will be
able to see many of these constellations, but he must look for them farther
toward the east than they are represented in the map. The bright stars in B=
oötes
and Virgo, for instance, instead of being over in the southwest, as in the =
map,
will be near the meridian; while Lyra, instead of shining high overhead, wi=
ll
be found climbing up out of the northeast. It would be well to begin at nine
o'clock, about the 1st of June, and watch the motions of the heavens for tw=
o or
three hours. At the commencement of the observations you will find the star=
s in
Boötes, Virgo, and Lyra in the positions I have just mentioned, while half-=
way
down the western sky will be seen the Sickle of Leo. The brilliant Procyon =
and
Capella will be found almost ready to set in the west and northwest,
respectively. Between Procyon and Capella, and higher above the horizon, sh=
ine
the twin stars in Gemini.
In an hour Procyon, Capella, and the Twins wil=
l be
setting, and Spica will be well past the meridian. In another hour the obse=
rver
will perceive that the constellations are approaching the places given to t=
hem
in our map, and at midnight he will find them all in their assigned positio=
ns.
A single evening spent in observations of this sort will teach him more abo=
ut
the places of the stars than he could learn from a dozen books.
Taking, now, the largest opera-glass you can g=
et
(I have before said that the diameter of the object-glasses should not be l=
ess
than 1.5 inch, and, I may add, the larger they are the better), find the co=
nstellation
Scorpio, and its chief star Antares. The map shows you where to look for it=
at
midnight on the 1st of June. If you prefer to begin at nine o'clock at that
date, then, instead of looking directly in the south for Scorpio, you must
expect to see it just rising in the southeast. You will recognize Antares by
its fiery color, as well as by the striking arrangement of its surrounding
stars. There are few constellations which bear so close a resemblance to the
objects they are named after as Scorpio. It does not require a very violent
exercise of the imagination to see in this long, winding trail of stars a
gigantic scorpion, with its head to the west, and flourishing its upraised
sting that glitters with a pair of twin stars, as if ready to strike. Reade=
rs of
the old story of Phaeton's disastrous attempt to drive the chariot of the S=
un
for a day will remember it was the sight of this threatening monster that so
terrified the ambitious youth as he dashed along the Zodiac, that he lost
control of Apollo's horses, and came near burning the earth up by running t=
he
Sun into it.
Antares rather gains in redness when viewed wi=
th a
glass. Its color is very remarkable, and it is a curious circumstance that =
with
powerful telescopes a small, bright-green star is seen apparently almost
touching it. Antares belongs to Secchi's third type of suns, that in which =
the spectroscopic
appearances suggest the existence of a powerfully absorptive atmosphere, and
which are believed on various grounds to be, as Lockyer has said, "in =
the
last visible stage of cooling"; in other words, almost extinct. This
great, red star probably in actual size exceeds our sun, and no one can help
feeling the sublime nature of those studies which give us reason to think t=
hat
here we can actually behold almost the expiring throes of a giant brother of
our giant sun. Only, the lifetime of a sun is many millions of years, and i=
ts
gradual extinction, even after it has reached a stage as advanced as that o=
f Antares
is supposed to be, may occupy a longer time than the whole duration of the
human race.
A little close inspection with the naked eye w=
ill
show three fifth- or sixth-magnitude stars above Antares and Sigma ([sigma]=
),
which form, with those stars, the figure of an irregular pentagon. An
opera-glass shows this figure very plainly. The nearest of these stars to
Antares, the one directly above it, is known by the number 22, and belongs =
to Scorpio,
while the farthest away, which marks the northernmost corner of the pentago=
n,
is Rho in Ophiuchus. Try a powerful field-glass upon the two stars just nam=
ed.
Take 22 first. You will without much difficulty perceive that it has a litt=
le
star under its wing, below and to the right, and more than twice as far away
above it there is another faint star. Then turn to Rho. Look sharp and you =
will
catch sight of two companion stars, one close to Rho on the right and a lit=
tle
below, and the other still closer and directly above Rho. The latter is qui=
te difficult
to be seen distinctly, but the sight is a very pretty one.
The opera-glass will show a number of faint st=
ars
scattered around Antares. Turn now to Beta ([beta]) in Scorpio, with the gl=
ass.
A very pretty pair of stars will be seen hanging below [beta]. Sweeping dow=
nward
from this point to the horizon you will find many beautiful star-fields. The
star marked Nu ([nu]) is a double which you will be able to separate with a
powerful field-glass, the distance between its components being 40".
And next let us look at a star-cluster. You wi=
ll
see on Map No. 8 an object marked 4 M, near Antares. Its designation means =
that
it is No. 4 in Messier's catalogue of nebulæ. It is not a true nebula, but a
closely compacted cluster of stars. With the opera-glass, if you are lookin=
g in
a clear and moonless night, you will see it as a curious nebulous speck. Wi=
th a
field-glass its real nature is more apparent, and it is seen to blaze brigh=
ter
toward the center. It is, in fact, one of those universes within the univer=
se
where thousands of suns are associated together by some unknown law of
aggregation into assemblages of whose splendor the slight view that we can =
get
gives us but the faintest conception.
The object above and to the right of Antares,
marked in the map 80 M., is a nebula, and although the nebula itself is too
small to be seen with an opera-glass (a field-glass shows it as a mere wisp=
of
light), yet there is a pretty array of small stars in its neighborhood worth
looking at. Besides, this nebula is of special interest, because in 1860 a =
star
suddenly took its place. At least, that is what seemed to have happened. Wh=
at
really did occur, probably, was that a variable or temporary star, situated
between us and the nebula, and ordinarily too faint to be perceived, receiv=
ed a
sudden and enormous accession of light, and blazed up so brightly as to blot
out of sight the faint nebula behind it. If this star should make its
appearance again, it could easily be seen with an opera-glass, and so it wi=
ll
not be useless for the reader to know where to look for it. The quarter of =
the
heavens with which we are now dealing is famous for these celestial
conflagrations, if so they may be called. The first temporary star of which
there is any record appeared in the constellation of the Scorpion, near the
head, 134 years before Christ. It must have been a most extraordinary
phenomenon, for it attracted attention all over the world, and both Greek a=
nd
Chinese annals contain descriptions of it. In 393 A. D. a temporary star sh=
one out
in the tail of Scorpio. In 827 A. D. Arabian astronomers, under the Caliph
Al-Mamoun, the son of Haroun-al-Raschid, who broke into the great pyramid,
observed a temporary star, that shone for four months in the constellation =
of
the Scorpion. In 1203 there was a temporary star, of a bluish color, in the
tail of Scorpio, and in 1578 another in the head of the constellation. Besi=
des
these there are records of the appearance of four temporary stars in the
neighboring constellation of Ophiuchus, one of which, that of 1604, is very
famous, and will be described later on. It is conceivable that these strange
outbursts in and near Scorpio may have had some effect in causing this
constellation to be regarded by the ancients as malign in its influence.
We shall presently see some examples of
star-clusters and nebulæ with which the instruments we are using are better
capable of dealing than with the one described above. In the mean time, let=
us
follow the bending row of stars from Antares toward the south and east. When
you reach the star Mu ([mu]), you are not unlikely to stop with an exclamat=
ion
of admiration, for the glass will separate it into two stars that, shining =
side
by side, seem trying to rival each other in brightness. But the next star b=
elow
[mu], marked Zeta ([zeta]), is even more beautiful. It also separates into =
two
stars, one being reddish and the other bluish in color. The contrast in a c=
lear
night is very pleasing. But this is not all. Above the two stars you will
notice a curious nebulous speck. Now, if you have a powerful field-glass, h=
ere
is an opportunity to view one of the prettiest sights in the heavens. The f=
ield-glass
not only makes the two stars appear brighter, and their colors more pronoun=
ced,
but it shows a third, fainter star below them, making a small triangle, and
brings other still fainter stars into sight, while the nebulous speck above
turns into a charmingly beautiful little star-cluster, whose components are=
so
close that their rays are inextricably mingled in a maze of light. This lit=
tle
cut is an attempt to represent the scene, but no engraving can reproduce the
life and sparkle of it.
Following the bend of the Scorpion's tail upwa=
rd,
we come to the pair of stars in the sting. These, of course, are thrown wid=
e apart
by the opera-glass. Then let us sweep off to the eastward a little way and =
find
the cluster known as 7 M. You will see it marked on the map. Above it, and =
near
enough to be included in the same field of view, is 6 M., a smaller cluster.
Both of these have a sparkling appearance with an opera-glass, and by close
attention some of the separate stars in 7 M. may be detected. With a
field-glass these clusters become much more striking and starry looking, and
the curious radiated structure of 7 M. comes out.
In lo=
oking
at such objects we can not too often recall to our minds the significance of
what we see--that these glimmering specks are the lights in the windows of =
the
universe which carry to us, across inconceivable tracts of space, the assur=
ance
that we and our little system are not alone in the heavens; that all around=
us,
and even on the very confines of immensity, Nature is busy, as she is here,=
and
the laws of light, heat, gravitation (and why not of life?), are in full
activity.
The clusters we have just been looking at lie =
on
the borders of Scorpio and Sagittarius. Let us cross over into the latter
constellation, which commemorates the centaur Chiron. We are now in another,
and even a richer, region of wonders. The Milky-Way, streaming down out of =
the northeast,
pours, in a luminous flood, through Sagittarius, inundating that whole regi=
on
of the heavens with seeming deeps and shallows, and finally bursting the
barriers of the horizon disappears, only to glow with redoubled splendor in=
the
southern hemisphere. The stars Zeta ([zeta]), Tau ([tau]), Sigma ([sigma]),=
Phi
([phi]), Lambda ([lambda]), and Mu ([mu]) indicate the outlines of a figure
sometimes called the Milk-Dipper, which is very evident when the eye has on=
ce
recognized it. On either side of the upturned handle of this dipper-like fi=
gure
lie some of the most interesting objects in the sky. Let us take the star [=
mu]
for a starting-point. Sweep downward and to the right a little way, and you
will be startled by a most singular phenomenon that has suddenly made its
appearance in the field of view of your glass. You may, perhaps, be tempted=
to
congratulate yourself on having got ahead of all the astronomers, and
discovered a comet. It is really a combination of a star-cluster with a neb=
ula,
and is known as 8 M. Sir John Herschel has described the "nebulous fol=
ds
and masses" and dark oval gaps which he saw in this nebula with his la=
rge
telescope at the Cape of Good Hope. But no telescope is needed to make it
appear a wonderful object; an opera-glass suffices for that, and a field-gl=
ass
reveals still more of its marvelous structure.
The reader will recollect that we found the su=
mmer
solstice close to a wonderful star-swarm in the feet of Gemini. Singularly
enough the winter solstice is also near a star-cluster. It is to be found n=
ear
a line drawn from 8 M. to the star [mu] Sagittarii, and about one third of =
the way
from the cluster to the star. There is another less conspicuous star-cluster
still closer to the solstitial point here, for this part of the heavens tee=
ms
with such aggregations.
On the opposite side of the star [mu]--that is=
to
say, above and a little to the left--is an entirely different but almost
equally attractive spectacle, the swarm of stars called 24 M. Here, again, =
the field-glass
easily shows its superiority over the opera-glass, for magnifying power is
needed to bring out the innumerable little twinklers of which the cluster is
composed. But, whether you use an opera-glass or a field-glass, do not fail=
to
gaze long and steadily at this island of stars, for much of its beauty beco=
mes
evident only after the eye has accustomed itself to disentangle the glimmer=
ing
rays with which the whole field of view is filled. Try the method of averted
vision, and hundreds of the finest conceivable points of light will seem to
spring into view out of the depths of the sky. The necessity of a perfectly=
clear
night, and the absence of moonlight, can not be too much insisted upon for
observations such as these. Everybody knows how the moonlight blots out the
smaller stars. A slight haziness, or smoke, in the air produces a similar
effect. It is as important to the observer with an opera-glass to have a
transparent atmosphere as it is to one who would use a telescope; but,
fortunately, the work of the former is not so much interfered with by curre=
nts
of air. Always avoid the neighborhood of any bright light. Electric lights =
in
particular are an abomination to star-gazers.
The cloud of stars we have just been looking a=
t is
in a very rich region of the Milky-Way, in the little modern constellation
called "Sobieski's Shield," which we have not named upon our map.
Sweeping slowly upward from 24 M. a little way with the field-glass, we will
pass in succession over three nebulous-looking spots. The second of these,
counting upward, is the famous Horseshoe nebula. Its wonders are beyond the
reach of our instrument, but its place may be recognized. Look carefully all
around this region, and you will perceive that the old gods, who traveled t=
his road
(the Milky-Way was sometimes called the pathway of the gods), trod upon gol=
den
sands. Off a little way to the east you will find the rich cluster called 2=
5 M.
But do not imagine the thousands of stars that your opera-glass or field-gl=
ass
reveals comprise all the riches of this Golconda of the heavens. You might =
ply
the powers of the greatest telescope in a vain attempt to exhaust its wealt=
h.
As a hint of the wonders that lie hidden here, let me quote Father Secchi's
description of a starry spot in this same neighborhood, viewed with the gre=
at telescope
at Rome. After telling of "beds of stars superposed upon one another,&=
quot;
and of the wonderful geometrical arrangement of the larger stars visible in=
the
field, he adds:
"The greater number are arranged in spiral
arcs, in which one can count as many as ten or twelve stars of the ninth to=
the
tenth magnitude following one another in a curve, like beads upon a string.
Sometimes they form rays which seem to diverge from a common focus, and, wh=
at
is very singular, one usually finds, either at the center of the rays, or at
the beginning of the curve, a more brilliant star of a red color, which see=
ms
to lead the march. It is impossible to believe that such an arrangement can=
be
accidental."
The reader will recall the somewhat similar
description that Admiral Smyth and Mr. Webb have given of a star-cluster in
Gemini (see Chapter I).
The milky look of the background of the Galaxy=
is,
of course, caused by the intermingled radiations of inconceivably minute and
inconceivably numerous stars, thousands of which become separately visible,=
the
number thus distinguishable varying with the size of the instrument. But th=
e most
powerful telescope yet placed in human hands can not sound these starry dee=
ps
to the bottom. The evidence given by Prof. Holden, the Director of the Lick
Observatory, on this point is very interesting. Speaking of the performance=
of
the gigantic telescope on Mount Hamilton, thirty-six inches in aperture, he
says:
"The Milky-Way is a wonderful sight, and I
have been much interested to see that there is, even with our superlative
power, no final resolution of its finer parts into stars. There is always t=
he
background of unresolved nebulosity on which hundreds and thousands of stars
are studded--each a bright, sharp, separate point."
The groups of stars forming the eastern half of
the constellation of Sagittarius are worth sweeping over with the glass, as=
a
number of pretty pairs may be found there.
Sagittarius stands in the old star-maps as a
centaur, half-horse-half-man, facing the west, with drawn bow, and arrow
pointed at the Scorpion.
Next let us pass to the double constellation
adjoining Scorpio and Sagittarius on the north--Ophiuchus and the Serpent.
These constellations, as our map shows, are curiously intermixed. The imagi=
nation
of the old star-gazers, who named them, saw here the figure of a giant gras=
ping
a writhing serpent with his hands. The head of the serpent is under the
Northern Crown, and its tail ends over the star-gemmed region that we have =
just
described, called "Sobieski's Shield." Ophiuchus stands, as figur=
ed
in Flamsteed's "Atlas," upon the back of the Scorpion, holding the
serpent with one hand below the neck, this hand being indicated by the pair=
of
stars marked Epsilon ([epsilon]) and Delta ([delta]), and with the other ne=
ar
the tail. The stars Tau ([tau]) and Nu ([nu]) indicate the second hand. The
giant's face is toward the observer, and the star Alpha ([alpha]), also cal=
led Ras
Alhague, shines in his forehead, while Beta ([beta]) and Gamma ([gamma]) ma=
rk
his right shoulder. Ophiuchus has been held to represent the famous physici=
an
Æsculapius. One may well repress the tendency to smile at these fanciful
legends when he reflects upon their antiquity. There is no doubt that this
double constellation is at least three thousand years old--that is to say, =
for
thirty centuries the imagination of men has continued to shape these stars =
into
the figures of a gigantic man struggling with a huge serpent. If it possess=
es
no other interest, then it at least has that which attaches to all things
ancient. Like many other of the constellations it has proved longer-lived t=
han
the mightiest nations. While Greece flourished and decayed, while Rome rose=
and
fell, while the scepter of civilization has passed from race to race, these
starry creations of fancy have shone on unchanged. The mind that would igno=
re
them now deserves compassion.
The reader will observe a little circle in the
map, and near it the figures 1604. This indicates the spot where one of the
most famous temporary stars on record appeared in the year 1604. At first it
was far brighter than any other star in the heavens; but it quickly faded, =
and in
a little over a year disappeared. It is particularly interesting, because
Kepler--the quaintest, and not far from the greatest, figure in astronomical
history--wrote a curious book about it. Some of the philosophers of the day
argued that the sudden outburst of the wonderful star was caused by the cha=
nce
meeting of atoms. Kepler's reply was characteristic, as well as amusing:
"I will tell those disputants, my opponen=
ts,
not my own opinion, but my wife's. Yesterday, when I was weary with writing=
, my
mind being quite dusty with considering these atoms, I was called to supper,
and a salad I had asked for was set before me. 'It seems, then,' said I, al=
oud,
'that if pewter dishes, leaves of lettuce, grains of salt, drops of water,
vinegar and oil, and slices of egg, had been flying about in the air from a=
ll
eternity, it might at last happen by chance that there would come a salad.'
'Yes,' says my wife, 'but not so nice and well-dressed as this of mine
is.'"
While there are no objects of special interest=
for
the observer with an opera-glass in Ophiuchus, he will find it worth while =
to
sweep over it for what he may pick up, and, in particular, he should look at
the group of stars southeast of [beta] and [gamma]. These stars have been
shaped into a little modern asterism called Taurus Poniatowskii, and it wil=
l be
noticed that five of them mark the outlines of a letter V, resembling the
well-known figure of the Hyades.
Also look at the stars in the head of Serpens,
several of which form a figure like a letter [X]. A little west of Theta
([theta]) in the tail of Serpens, is a beautiful swarm of little stars, upon
which a field-glass may be used with advantage. The star [theta] is itself =
a charming
double, just within the separating power of a very powerful field-glass und=
er
favorable circumstances, the component stars being only about one third of a
minute apart.
Do not fail to notice the remarkable subdivisi=
ons
of the Milky-Way in this neighborhood. Its current seems divided into numer=
ous
channels and bays, interspersed with gaps that might be likened to islands,=
and
the star [theta] appears to be situated upon one of these islands of the ga=
laxy.
This complicated structure of the Milky-Way extends downward to the horizon,
and upward through the constellation Cygnus, and of its phenomenal appearan=
ce
in that region we shall have more to say further on.
Directly north of Ophiuchus is the constellati=
on
Hercules, interesting as occupying that part of the heavens toward which the
proper motion of the sun is bearing the earth and its fellow-planets, at the
rate, probably, of not less than 160,000,000 miles in a year--a stupendous =
voyage
through space, of whose destination we are as ignorant as the crew of a ship
sailing under sealed orders, and, like whom, we must depend upon such
inferences as we can draw from courses and distances, for no other informat=
ion
comes to us from the flagship of our squadron.
In the accompanying map we have represented the
beautiful constellations Lyra and the Northern Crown, lying on either side =
of
Hercules. The reader should note that the point overhead in this map is not=
far
from the star Eta ([eta]) in Hercules. The bottom of the map is toward the =
south,
the right-hand side is west, and the left-hand side east. It is important to
keep these directions in mind, in comparing the map with the sky. For insta=
nce,
the observer must not expect to look into the south and see Hercules half-w=
ay
up the sky, with Lyra a little east of it; he must look for Hercules nearly
overhead, and Lyra a little east of the zenith. The same precautions are not
necessary in using the maps of Scorpio, Sagittarius, and Ophiuchus, because
those constellations are nearer the horizon, and so the observer does not h=
ave
to imagine the map as being suspended over his head.
The name Hercules sufficiently indicates the
mythological origin of the constellation, and yet the Greeks did not know i=
t by
that name, for Aratus calls it "the Phantom whose name none can
tell." The Northern Crown, according to fable, was the celebrated crow=
n of
Ariadne, and Lyra was the harp of Orpheus himself, with whose sweet music he
charmed the hosts of Hades, and persuaded Pluto to yield up to him his lost=
Eurydice.
With the aid of the map you will be able to
recognize the principal stars and star-groups in Hercules, and will find ma=
ny
interesting combinations of stars for yourself. An object of special intere=
st
is the celebrated star-cluster 13 M. You will find it on the map between th=
e stars
Eta ([eta]) and Zeta ([zeta]). While an opera-glass will only show it as a
faint and minute speck, lying nearly between two little stars, it is
nevertheless well worth looking for, on account of the great renown of this
wonderful congregation of stars. Sir William Herschel computed the number of
stars contained in it as about fourteen thousand. It is roughly spherical in
shape, though there are many straggling stars around it evidently connected
with the cluster. In short, it is a ball of suns. The reader should not mis=
take
what that implies, however. These suns, though truly solar bodies, are prob=
ably
very much smaller than our sun. Mr. Gore has computed their average diamete=
r to
be forty-five thousand miles, and the distance separating each from the nex=
t to
be 9,000,000,000 miles. It may not be uninteresting to inquire what would be
the appearance of the sky to dwellers within such a system of suns. Adopting
Mr. Gore's estimates, and supposing 9,000,000,000 miles to be very nearly t=
he
uniform distance apart of the stars in the cluster, and forty-five thousand
miles their uniform diameter, then, starting with a single star in the cent=
er,
their arrangement might be approximately in concentric spherical shells,
situated about 9,000,000,000 miles apart. The first shell, counting outward
from the center, would contain a dozen stars, each of which, as seen by an =
observer
stationed upon a planet at the center of the cluster, would shine eleven
hundred times as bright as Sirius appears to us. The number of the stars in
each shell would increase as they receded from the center in proportion to =
the
squares of the radii of the successive shells, while their luminosity, as s=
een
from the center, would vary inversely as those squares. Still, the outermost
stars--the total number being limited to fourteen or fifteen thousand--would
appear to our observer at the center of the system about five times as
brilliant as Sirius.
It is clear, then, that he would be dwelling i=
n a
sort of perpetual daylight. His planet might receive from the particular sun
around which it revolved as brilliant a daylight as our sun gives to us, but
let us see what would be the illumination of its night side. Adopting Zölln=
er's
estimate of the light of the sun as 618,000 times as great as that of the f=
ull
moon, and choosing among the various estimates of the light of Sirius as
compared with the sun 1/4000000000 as probably the nearest the truth, we fi=
nd
that the moon sends us about sixty-five hundred times as much light as Siri=
us
does. Now, since the dozen stars nearest the center of the cluster would ea=
ch
appear to our observer eleven hundred times as bright as Sirius, all of them
together would give a little more than twice as much light as the full moon
sheds upon the earth. But as only half the stars in the cluster would be ab=
ove
the horizon at once we must diminish this estimate by one half, in order to
obtain the amount of light that our supposititious planet would receive on =
its
night side from the nearest stars in the cluster. And since the number of t=
hese
stars increases with their distance from the center in the same ratio as th=
eir
light diminishes, it follows that the total light received from the cluster
would exceed that received from the dozen nearest stars as many times as th=
ere
were spherical shells in the cluster. This would be about fifteen times, and
accordingly all the stars together would shed, at the center, some thirty t=
imes
as much light as that of the moon. Dividing this again by two, because only
half of the stars could be seen at once, we find that the night side of our
observer's planet would be illuminated with fifteen times as much light as =
the
full moon sheds upon the earth.
It is evident, too, that our observer would en=
joy
the spectacle of a starry firmament incomparably more splendid than that wh=
ich
we behold. Only about three thousand stars are visible to our unassisted ey=
es
at once on any clear night, and of those only a few are conspicuous, and two
thirds are so faint that they require some attention in order to be disting=
uished.
But the spectator at the center of the Hercules cluster would behold some s=
even
thousand stars at once, the faintest of which would be five times as brilli=
ant
as the brightest star in our sky, while the brighter ones would blaze like
nearing suns. One effect of this flood of starlight would be to shut out fr=
om
our observer's eyes all the stars of the outside universe. They would be
effaced in the blaze of his sky, and he would be, in a manner, shut up with=
in
his own little star-system, knowing nothing of the greater universe beyond,=
in
which we behold his multitude of luminaries, diminished and blended by dist=
ance
into a faintly shining speck, floating like a silvery mote in a sunbeam.
If our observer's planet, instead of being
situated in the center of the cluster, circled around one of the stars at t=
he
outer edge of it, the appearance of his sky would be, in some respects, sti=
ll
more wonderful, the precise phenomena depending upon the position of the
planet's orbit and the station of the observer. Less than half of his sky w=
ould
be filled, at any time, by the stars of the cluster, the other half opening=
upon
outer space and appearing by comparison almost starless--a vast, cavernous
expanse, with a few faint glimmerings out of its gloomy depths. The plane of
the orbit of his planet being supposed to pass through the center of the
spherical system, our observer would, during his year, behold the night at =
one
season blazing with the splendors of the clustered suns, and at another emp=
tied
of brilliant orbs and faintly lighted with the soft glow of the Milky-Way a=
nd
the feeble flickering of distant stars, scattered over the dark vault. The
position of the orbit, and the inclination of the planet's axis might be su=
ch
that the glories of the cluster would not be visible from one of its
hemispheres, necessitating a journey to the other side of the globe to beho=
ld them.[B]
[B=
] A
similar calculation of the internal appearances of the Hercules cluster, which I made, w=
as
published in 1887 in the
"New York Sun."
Of course, it is not to be assumed that the
arrangement of the stars in the cluster actually is exactly that which we h=
ave
imagined. Still, whatever the arrangement, so long as the cluster is
practically spherical, and the stars composing it are of nearly uniform size
and situated at nearly uniform distances, the phenomena we have described w=
ould
fairly represent the appearances presented to inhabitants of worlds situate=
d in
such a system. As to the possibility of the existence of such worlds and
inhabitants, everybody must draw his own conclusions. Astronomy, as a scien=
ce,
is silent upon that question. But there shine the congregated stars, mingli=
ng
their rays in a message of light, that comes to us across the gulf, proclai=
ming
their brotherhood with our own glorious sun. Mathematicians can not unravel=
the
interlocking intricacies of their orbits, and some would, perhaps a priori,
have said that such a system was impossible, but the telescope has revealed=
them,
and there they are! What purposes they subserve in the economy of the unive=
rse,
who shall declare?
If you have a field-glass, by all means try it
upon 13 M. It will give you a more satisfactory view than an opera-glass is
capable of doing, and will magnify the cluster so that there can be no
possibility of mistaking it for a star. Compare this compact cluster, which
only a powerful telescope can partially resolve into its component stars, w=
ith 7
M. and 24 M., described before, in order to comprehend the wide variety in =
the
structure of these aggregations of stars.
The Northern Crown, although a strikingly
beautiful constellation to the naked eye, offers few attractions to the
opera-glass. Let us turn, then, to Lyra. I have never been able to make up =
my
mind which of three great stars is entitled to precedence--Vega, the leading
brilliant of Lyra, Arcturus in Boötes, or Capella in Auriga. They are the t=
hree
leaders of the northern firmament, but which of them should be called the
chief, is very hard to say. At any rate, Vega would probably be generally
regarded as the most beautiful, on account of the delicate bluish tinge in =
its light,
especially when viewed with a glass. There is no possibility of mistaking t=
his
star because of its surpassing brilliancy. Two faint stars close to Vega on=
the
east make a beautiful little triangle with it, and thus form a further mean=
s of
recognition, if any were needed. Your opera-glass will show that the floor =
of
heaven is powdered with stars, fine as the dust of a diamond, all around the
neighborhood of Vega, and the longer you gaze the more of these diminutive
twinklers you will discover.
Now direct your glass to the northernmost of t=
he
two little stars near Vega, the one marked Epsilon ([epsilon]) in the map. =
You
will perceive that it is composed of two stars of almost equal magnitude. If
you had a telescope of considerable power, you would find that each of these
stars is in turn double. In other words, this wonderful star which appears =
single
to the unassisted eye, is in reality quadruple, and there is reason to think
that the four stars composing it are connected in pairs, the members of each
pair revolving around their common center while the two pairs in turn circle
around a center common to all. With a field-glass you will be able to see t=
hat
the other star near Vega, Zeta ([zeta]), is also double, the distance betwe=
en
its components being three quarters of a minute, while the two stars in
[epsilon] are a little less than 3œ' apart. The star Beta ([beta]) is
remarkably variable in brightness. You may watch these variations, which ru=
n through
a regular period of about 12 days, 21Ÿ hours, for yourself. Between Beta and
Gamma ([gamma]) lies the beautiful Ring nebula, but it is hopelessly beyond=
the
reach of the optical means we are employing.
Let us turn next to the stars in the west. In
consulting the accompanying map of Virgo and Boötes (Map No. 11), the obser=
ver
is supposed to face the southwest, at the hours and dates mentioned above as
those to which the circular map corresponds. He will then see the bright st=
ar
Spica in Virgo not far above the horizon, while Arcturus will be half-way up
the sky, and the Northern Crown will be near the zenith.
The constellation Virgo is an interesting one =
in
mythological story. Aratus tells us that the Virgin's home was once on eart=
h,
where she bore the name of Justice, and in the golden age all men obeyed he=
r.
In the silver age her visits to men became less frequent, "no longer f=
inding
the spirits of former days"; and, finally, when the brazen age came wi=
th the
clangor of war:
"Justice, loathing that race of men, Winged her flight to heaven; and fixed=
Her station in that region Where still by night is seen The Virgin goddess near to bright
Boötes."
The chief star of Virgo, Spica, is remarkable =
for
its pure white light. To my eye there is no conspicuous star in the sky equ=
al
to it in this respect, and it gains in beauty when viewed with a glass. With
the aid of the map the reader will find the celebrated binary star Gamma ([=
gamma])
Virginis, although he will not be able to separate its components without a
telescope. It is a curious fact that the star Epsilon ([epsilon]) in Virgo =
has
for many ages been known as the Grape-Gatherer. It has borne this name in
Greek, in Latin, in Persian, and in Arabic, the origin of the appellation
undoubtedly being that it was observed to rise just before the sun in the
season of the vintage. It will be observed that the stars [epsilon], [delta=
],
[gamma], [eta], and [beta], mark two sides of a quadrilateral figure of whi=
ch
the opposite corner is indicated by Denebola in the tail of Leo. Within thi=
s quadrilateral
lies the marvelous Field of the Nebulæ, a region where with adequate optical
power one may find hundreds of these strange objects thronging together, a =
very
storehouse of the germs of suns and worlds. Unfortunately, these nebulæ are=
far
beyond the reach of an opera-glass, but it is worth while to know where this
curious region is, even if we can not behold the wonders it contains. The s=
tars
Omicron ([omicron]), Pi ([pi]), etc., forming a little group, mark the head=
of Virgo.
The autumnal equinox, or the place where the s=
un
crosses the equator of the heavens on his southerly journey about the 21st =
of
September, is situated nearly between the stars [eta] and [beta] Virginis, a
little below the line joining them, and somewhat nearer to [eta]. Both [eta=
] and
[zeta] Virginis are almost exactly upon the equator of the heavens.
The constellation Libra, lying between Virgo a=
nd
Scorpio, does not contain much to attract our attention. Its two chief star=
s,
[alpha] and [beta], may be readily recognized west of and above the head of
Scorpio. The upper one of the two, [beta], has a singular greenish tint, and
the lower one, [alpha], is a very pretty double for an opera-glass.
The constellation of Libra appears to have bee=
n of
later date than the other eleven members of the zodiacal circle. Its two ch=
ief
stars at one time marked the extended claws of Scorpio, which were afterward
cut off (perhaps the monster proved too horrible even for its inventors) to
form Libra. As its name signifies, Libra represents a balance, and this fac=
t seems
to refer the invention of the constellation back to at least three hundred
years before Christ, when the autumnal equinox occurred at the moment when =
the
sun was just crossing the western border of the constellation. The equality=
of
the days and nights at that season readily suggests the idea of a balance.
Milton, in "Paradise Lost," suggests another origin for the
constellation of the Balance in the account of Gabriel's discovery of Satan=
in
paradise:
"... Now dreadful deeds Might have ensued, nor only paradise In this commotion, but the starry cope =
Of heaven, perhaps, or all the elements=
At least had gone to wrack, disturbed a=
nd
torn With violence of this confli=
ct,
had not soon The Eternal, to prev=
ent
such horrid fray, Hung forth in h=
eaven
his golden scales, yet seen Betwi=
xt
Astrea and the Scorpion sign."
Just north of Virgo's head will be seen the
glimmering of Berenice's Hair. This little constellation was included among
those described in the chapter on "The Stars of Spring," but it is
worth looking at again in the early summer, on moonless nights, when the
singular arrangement of the brighter members of the cluster at once strikes=
the
eye.
Boötes, whose leading brilliant, Arcturus,
occupies the center of our map, also possesses a curious mythical history. =
It
is called by the Greeks the Bear-Driver, because it seems continually to ch=
ase
Ursa Major, the Great Bear, in his path around the pole. The story is that =
Boötes
was the son of the nymph Calisto, whom Juno, in one of her customary fits of
jealousy, turned into a bear. Boötes, who had become a famous hunter, one d=
ay
roused a bear from her lair, and, not knowing that it was his mother, was a=
bout
to kill her, when Jupiter came to the rescue and snatched them both up into=
the
sky, where they have shone ever since. Lucan refers to this story when,
describing Brutus's visit to Cato at night, he fixes the time by the positi=
on
of these constellations in the heavens:
"'Twas when the solemn dead of night came on, When bright Calisto, with her shining s=
on, Now half the circle round the pole had
run."
Boötes is not specially interesting for our
purposes, except for the splendor of Arcturus. This star has possessed a
peculiar charm for me ever since boyhood, when, having read a description o=
f it
in an old treatise on Uranography, I felt an eager desire to see it. As my
search for it chanced to begin at a season when Arcturus did not rise till =
after
a boy's bed-time, I was for a long time disappointed, and I shall never for=
get
the start of surprise and almost of awe with which I finally caught sight of
it, one spring evening, shooting its flaming rays through the boughs of an
apple-orchard, like a star on fire.
When near the horizon, Arcturus has a remarkab=
ly
reddish color; but, after it has attained a high elevation in the sky, it
appears rather a deep yellow than red. There is a scattered cluster of small
stars surrounding Arcturus, forming an admirable spectacle with an opera-gl=
ass on
a clear night. To see these stars well, the glass should be slowly moved ab=
out.
Many of them are hidden by the glare of Arcturus. The little group of stars
near the end of the handle of the Great Dipper, or, what is the same thing,=
the
tail of the Great Bear, marks the upraised hand of Boötes. Between Berenice=
's
Hair and the tail of the Bear you will see a small constellation called Can=
es
Venatici, the Hunting-Dogs. On the old star-maps Boötes is represented as
holding these dogs with a leash, while they are straining in chase of the B=
ear.
You will find some pretty groupings of stars in this constellation.
And now we will turn to the east. Our next map
shows Cygnus, a constellation especially remarkable for the large and strik=
ing
figure that it contains, called the Northern Cross, Aquila the Eagle, the D=
olphin,
and the little asterisms Sagitta and Vulpecula. In consulting the map, the
observer is supposed to face toward the east. In Aquila the curious arrange=
ment
of two stars on either side of the chief star of the constellation, called
Altair, at once attracts the eye. Within a circle including the two attenda=
nts
of Altair you will probably be able to see with the naked eye only two or t=
hree
stars in addition to the three large ones. Now turn your glass upon the same
spot, and you will see eight or ten times as many stars, and with a field-g=
lass
still more can be seen. Watch the star marked Eta ([eta]), and you will find
that its light is variable, being sometimes more than twice as bright as at=
other
times. Its changes are periodical, and occupy a little over a week.
The Eagle is fabled to have been the bird that
Jupiter kept beside his throne. A constellation called Antinous, invented by
Tycho Brahe, is represented on some maps as occupying the lower portion of =
the
space given to Aquila.
The Dolphin is an interesting little
constellation, and the ancients said it represented the very animal on whose
back the famous musician Arion rode through the sea after his escape from t=
he
sailors who tried to murder him. But some modern has dubbed it with the less
romantic name of Job's Coffin, by which it is sometimes called. It presents=
a
very pretty sight to the opera-glass.
Cygnus, the swan, is a constellation whose
mythological history is not specially interesting, although, as remarked ab=
ove,
it contains one of the most clearly marked figures to be found among the st=
ars,
the famous Northern Cross. The outlines of this cross are marked with great=
distinctness
by the stars Alpha ([alpha]), Epsilon ([epsilon]), Gamma ([gamma]), Delta
([delta]), and Beta ([beta]), together with some fainter stars lying along =
the
main beam of the cross between [beta] and [gamma]. The star [beta], also ca=
lled
Albireo, is one of the most beautiful double stars in the heavens. The
components are sharply contrasted in color, the larger star being
golden-yellow, while the smaller one is a deep, rich blue. With a field-gla=
ss
of 1.6-inch aperture and magnifying seven times I have sometimes been able =
to divide
this pair, and to recognize the blue color of the smaller star. It will be
found a severe test for such a glass.
About half-way from Albireo to the two stars
[zeta] and [epsilon] in Aquila is a very curious little group, consisting of
six or seven stars in a straight row, with a garland of other stars hanging
from the center. To see it best, take a field-glass, although an opera-glas=
s shows
it.
I have indicated the place of the celebrated s=
tar
61 Cygni in the map, because of the interest attaching to it as the nearest=
to
us, so far as we know, of all the stars in the northern hemisphere, and with
one exception the nearest star in all the heavens. Yet it is very faint, an=
d the
fact that so inconspicuous a star should be nearer than such brilliants as =
Vega
and Arcturus shows how wide is the range of magnitude among the suns that l=
ight
the universe. The actual distance of 61 Cygni is something like 650,000 tim=
es
as great as the distance from the earth to the sun.
The star Omicron ([omicron]) is very interesti=
ng
with an opera-glass. The naked eye sees a little star near it. The glass th=
rows
them wide apart, and divides [omicron] itself into two stars. Now, a
field-glass, if of sufficient power, will divide the larger of these stars
again into two--a fine test.
Sweep around [alpha] and [gamma] for the splen=
did
star-fields that abound in this neighborhood; also around the upper part of=
the
figure of the cross. We are here in one of the richest parts of the Milky-W=
ay. Between
the stars [alpha], [gamma], [epsilon], is the strange dark gap in the galaxy
called the Coal-Sack, a sort of hole in the starry heavens. Although it is =
not
entirely empty of stars, its blackness is striking in contrast with the
brilliancy of the Milky-Way in this neighborhood. The divergent streams of =
the
great river of light in this region present a very remarkable appearance.
Finally, we come to the great dragon of the sk=
y.
In using the map of Draco and the neighboring constellations, the reader is
supposed to face the north. The center of the upper edge of the map is dire=
ctly
over the observer's head. One of the stories told of this large constellati=
on
is that it represents a dragon that had the temerity to war against Minerva.
The goddess "seized it in her hand, and hurled it, twisted as it was, =
into
the heavens round the axis of the world, before it had time to unwind its
contortions." Others say it is the dragon that guarded the golden appl=
es
in the Garden of the Hesperides, and that was slain by the redoubtable
Hercules. At any rate, it is plainly a monster of the first magnitude. The
stars [beta], [gamma], [xi], [nu], and [mu] represent its head, while its b=
ody
runs trailing along, first sweeping in a long curve toward Cepheus, and then
bending around and passing between the two bears. Try [nu] with your
opera-glass, and if you succeed in seeing it double you may congratulate
yourself on your keen sight. The distance between the stars is about 1'. No=
tice
the contrasted colors of [gamma] and [beta], the former being a rich orange=
and
the latter white. As you sweep along the winding way that Draco follows, you
will run across many striking fields of stars, although the heavens are not=
as
rich here as in the splendid regions that we have just left. You will also =
find
that Cepheus, although not an attractive constellation to the naked eye, is=
worth
some attention with an opera-glass. The head and upper part of the body of
Cepheus are plunged in the stream of the Milky Way, while his feet are dire=
cted
toward the pole of the heavens, upon which he is pictured as standing. Ceph=
eus,
however, sinks into insignificance in comparison with its neighbor Cassiope=
ia,
but that constellation belongs rather to the autumn sky, and we shall pass =
it
by here.
IN the
"Fifth Evening" of that delightful, old, out-of-date book of Font=
enelle's,
on the "Plurality of Worlds," the Astronomer and the Marchioness,=
who
have been making a wonderful pilgrimage through the heavens during their
evening strolls in the park, come at last to the starry systems beyond the
"solar vortex," and the Marchioness experiences a lively impatien=
ce
to know what the fixed stars will turn out to be, for the Astronomer has
sharpened her appetite for marvels.
"Tell me," says she, eagerly, "=
are
they, too, inhabited like the planets, or are they not peopled? In short, w=
hat
can we make of them?"
The Astronomer answers his charming questioner=
, as
we should do to-day, that the fixed stars are so many suns. And he adds to =
this
information a great deal of entertaining talk about the planets that may be
supposed to circle around these distant suns, interspersing his conversation
with explanations of "vortexes," and many quaint conceits, in whi=
ch
he is helped out by the ready wit of the Marchioness.
Finally, the impressionable mind of the lady is
overwhelmed by the grandeur of the scenes that the Astronomer opens to her
view, her head swims, infinity oppresses her, and she cries for mercy.
"You show me," she exclaims, "a
perspective so interminably long that the eye can not see the end of it. I =
see
plainly the inhabitants of the earth; then you cause me to perceive those of
the moon and of the other planets belonging to our vortex (system), quite
clearly, yet not so distinctly as those of the earth. After them come the
inhabitants of planets in the other vortexes. I confess, they seem to me hi=
dden
deep in the background, and, however hard I try, I can barely glimpse them =
at all.
In truth, are they not almost annihilated by the very expression which you =
are
obliged to use in speaking of them? You have to call them inhabitants of on=
e of
the planets contained in one out of the infinity of vortexes. Surely we our=
selves,
to whom the same expression applies, are almost lost among so many millions=
of
worlds. For my part, the earth begins to appear so frightfully little to me
that henceforth I shall hardly consider any object worthy of eager pursuit.
Assuredly, people who seek so earnestly their own aggrandizement, who lay
schemes upon schemes, and give themselves so much trouble, know nothing of =
the vortexes!
I am sure my increase of knowledge will redound to the credit of my idlenes=
s,
and when people reproach me with indolence I shall reply: 'Ah! if you but k=
new
the history of the fixed stars!'"
It is certainly true that a contemplation of t=
he
unthinkable vastness of the universe, in the midst of which we dwell upon a
speck illuminated by a spark, is calculated to make all terrestrial affairs
appear contemptibly insignificant. We can not wonder that men for ages rega=
rded
the earth as the center, and the heavens with their lights as tributary to =
it,
for to have thought otherwise, in those times, would have been to see things
from the point of view of a superior intelligence. It has taken a vast amou=
nt
of experience and knowledge to convince men of the parvitude of themselves =
and
their belongings. So, in all ages they have applied a terrestrial measure to
the universe, and imagined they could behold human affairs reflected in the
heavens and human interests setting the gods together by the ears.
This is clearly shown in the story of the
constellations. The tremendous truth that on a starry night we look, in eve=
ry
direction, into an almost endless vista of suns beyond suns and systems upon
systems, was too overwhelming for comprehension by the inventors of the
constellations. So they amused themselves, like imaginative children, as th=
ey
were, by tracing the outlines of men and beasts formed by those pretty ligh=
ts, the
stars. They turned the starry heavens into a scroll filled with pictured
stories of mythology. Four of the constellations with which we are going to
deal in this chapter are particularly interesting on this account. They
preserve in the stars, more lasting than parchment or stone, one of the old=
est
and most pleasing of all the romantic stories that have amused and inspired=
the
minds of men--the story of Perseus and Andromeda--a better story than any t=
hat
modern novelists have invented. The four constellations to which I refer be=
ar
the names of Andromeda, Perseus, Cassiopeia, and Cepheus, and are sometimes
called, collectively, the Royal Family. In the autumn they occupy a conspic=
uous
position in the sky, forming a group that remains unrivaled until the risin=
g of
Orion with his imperial cortége. The reader will find them in Map No. 14,
occupying the northeastern quarter of the heavens.
This map represents the visible heavens at abo=
ut
midnight on September 1st, ten o'clock P. M. on October 1st, and eight o'cl=
ock
P. M. on November 1st. At this time the constellations that were near the m=
eridian
in summer will be found sinking in the west, Hercules being low in the
northwest, with the brilliant Lyra and the head of Draco suspended above it;
Aquila, "the eagle of the winds," soars high in the southwest; wh=
ile
the Cross of Cygnus is just west of the zenith; and Sagittarius, with its
wealth of star-dust, is disappearing under the horizon in the southwest.
Far down in the south the observer catches the
gleam of a bright lone star of the first magnitude, though not one of the
largest of that class. It is Fomalhaut, in the mouth of the Southern Fish,
Piscis Australis. A slight reddish tint will be perceived in the light of t=
his beautiful
star, whose brilliance is enhanced by the fact that it shines without a riv=
al
in that region of the sky. Fomalhaut is one of the important "nautical
stars," and its position was long ago carefully computed for the benef=
it
of mariners. The constellation of Piscis Australis, which will be found in =
our
second map, does not possess much to interest us except its splendid leading
star. In consulting Map 15, the observer is supposed to be facing south, or
slightly west of south, and he must remember that the upper part of the map
reaches nearly to the zenith, while at the bottom it extends down to the
horizon.
To the right, or west, of Fomalhaut, and higher
up, is the constellation of Capricornus, very interesting on many accounts,
though by no means a striking constellation to the unassisted eye. The stars
Alpha ([alpha]), called Giedi, and Beta ([beta]), called Dabih, will be rea=
dily
recognized, and a keen eye will perceive that Alpha really consists of two
stars. They are about six minutes of arc apart, and are of the third and the
fourth magnitude respectively. These stars, which to the naked eye appear
almost blended into one, really have no physical connection with each other,
and are slowly drifting apart. The ancient astronomers make no mention of G=
iedi
being composed of two stars, and the reason is plain, when it is known that=
in
the time of Hipparchus, as Flammarion has pointed out, their distance apart=
was
not more than two thirds as great as it is at present, so that the naked eye
could not have detected the fact that there were two of them; and it was not
until the seventeenth century that they got far enough asunder to begin to =
be separated
by eyes of unusual power. With an ordinary opera-glass they are thrown well
apart, and present a very pretty sight. Considering the manner in which the=
se
stars are separating, the fact that both of them have several faint compani=
ons,
which our powerful telescopes reveal, becomes all the more interesting. A
suggestion of Sir John Herschel, concerning one of these faint companions, =
that
it shines by reflected light, adds to the interest, for if the suggestion is
well founded the little star must, of course, be actually a planet, and
granting that, then some of the other faint points of light seen there are
probably planets too. It must be said that the probabilities are against He=
rschel's
suggestion. The faint stars more likely shine with their own light. Even so,
however, these two systems, which apparently have met and are passing one
another, at a distance small as compared with the space that separates them
from us, possess a peculiar interest, like two celestial fleets that have
spoken one another in the midst of the ocean of space.
The star Beta, or Dabih, is also a double star.
The companion is of a beautiful blue color, generally described as
"sky-blue." It is of the seventh magnitude, while the larger star=
is
of magnitude three and a half. The latter is golden-yellow. The blue of the
small star can be seen with either an opera- or a field-glass, but it requi=
res
careful looking and a clear and steady atmosphere. I recollect discovering =
the color
of this star with a field-glass, and exclaiming to myself, "Why, the
little one is as blue as a bluebell!" before I knew that that was its =
hue
as seen with a telescope. Trying my opera-glass upon it I found that the co=
lor
was even more distinct, although the small star was then more or less envel=
oped
in the yellow rays of the large one. The distance between the two stars in
Dabih is nearly the same as that between the components of [epsilon] Lyræ, =
and
the comparative difficulty of separating them is an instructive example of =
the
effect of a large star in concealing a small one close beside it. The two s=
tars
in [epsilon] Lyræ are of nearly equal brightness, and are very easily separ=
ated
and distinguished, but in [beta] Capricorni, or Dabih, one star is about tw=
enty
times as bright as the other, and consequently the fainter star is almost
concealed in the glare of its more brilliant neighbor.
With the most powerful glass at your disposal,
sweep from the star Zeta ([zeta]) eastward a distance somewhat greater than
that separating Alpha and Beta, and you will find a fifth-magnitude star be=
side
a little nebulous spot. This is the cluster known as 30 M, one of those sun=
-swarms
that overwhelm the mind of the contemplative observer with astonishment, and
especially remarkable in this case for the apparent vacancy of the heavens
immediately surrounding the cluster, as if all the stars in that neighborho=
od
had been drawn into the great assemblage, leaving a void around it. Of cour=
se,
with the instrument that our observer is supposed to be using, merely the
existence of this solar throng can be detected; but, if he sees that it is
there, he may be led to provide himself with a telescope capable of reveali=
ng
its glories.
Admiral Smyth remarks that, "although
Capricorn is not a striking object, it has been the very pet of all
constellations with astrologers," and he quotes from an old almanac of=
the
year 1386, that "whoso is borne in Capcorn schal be ryche and wel
lufyd." The mythological account of the constellation is that it
represents the goat into which Pan was turned in order to escape from the g=
iant
Typhon, who once on a time scared all the gods out of their wits, and caused
them to change themselves into animals, even Jupiter assuming the form of a
ram. According to some authorities, Piscis Australis represents the fish in=
to which
Venus changed herself on that interesting occasion.
Directly above Piscis Australis, and to the ea=
st
or left of Capricorn, the map shows the constellation of Aquarius, or the
Water-Bearer. Some say this commemorates Ganymede, the cup-bearer of the go=
ds.
It is represented in old star-maps by the figure of a young man pouring wat=
er from
an urn. The star Alpha ([alpha]) marks his right shoulder, and Beta ([beta])
his left, and Gamma ([gamma]), Zeta ([zeta]), Eta ([eta]), and Pi ([pi])
indicate his right hand and the urn. From this group a current of small sta=
rs
will be recognized, sweeping downward with a curve toward the east, and end=
ing
at Fomalhaut; this represents the water poured from the urn, which the Sout=
hern
Fish appears to be drinking. In fact, according to the pictures in the old
maps, the fish succeeds in swallowing the stream completely, and it vanishes
from the sky in the act of entering his distended mouth! It is worthy of re=
mark
that in Greek, Latin, and Arabic this constellation bears names all of whic=
h signify
"a man pouring water." The ancient Egyptians imagined that the se=
tting
of Aquarius caused the rising of the Nile, as he sank his huge urn in the r=
iver
to fill it. Alpha Aquarii was called by the Arabs Sadalmelik, which is
interpreted to mean the "king's lucky star," but whether it proved
itself a lucky star in war or in love, and what particular king enjoyed its
benign influence and recorded his gratitude in its name, we are not informe=
d.
Thus, at every step, we find how shreds of history and bits of superstition=
are
entangled among the stars. Surely, humanity has been reflected in the heave=
ns
as lastingly as it has impressed itself upon the earth.
Starting from the group of stars just describe=
d as
forming the Water-Bearer's urn, follow with a glass the winding stream of s=
mall
stars that represent the water. Several very pretty and striking assemblage=
s of
stars will be encountered in its course. The star Tau ([tau]) is double and
presents a beautiful contrast of color, one star being white and the other
reddish-orange--two solar systems, it may be, apparently neighbors as seen =
from
the earth, in one of which daylight is white and in the other red!
Point a good glass upon the star marked Nu ([n=
u]),
and you will see, somewhat less than a degree and a half to the west of it,
what appears to be a faint star of between the seventh and eighth magnitude=
s.
You will have to look sharp to see it. It is with your mind's eye that you =
must
gaze, in order to perceive the wonder here hidden in the depths of space. T=
hat
faint speck is a nebula, unrivaled for interest by many of the larger and m=
ore
conspicuous objects of that kind. Lord Rosse's great telescope has shown th=
at
in form it resembles the planet Saturn; in other words, that it consists
apparently of a ball surrounded by a ring. But the spectroscope proves that=
it
is a gaseous mass, and the micrometer--supposing its distance to be equal to
that of the stars, and we have no reason to think it less--that it must be
large enough to fill the whole space included within the orbit of Neptune!
Here, then, as has been said, we seem to behold a genesis in the heavens. If
Laplace's nebular hypothesis, or any of the modifications of that hypothesi=
s, represents
the process of formation of a solar system, then we may fairly conclude that
such a process is now actually in operation in this nebula in Aquarius, whe=
re a
vast ring of nebulous matter appears to have separated off from the spheric=
al
mass within it. This may not be the true explanation of what we see there, =
but,
whatever the explanation is, there can be no question of the high significa=
nce
of this nebula, whose shape proclaims unmistakably the operation of great
metamorphic forces there. Of course, with his insignificant optical means, =
our
observer can see nothing of the strange form of this object, the detection =
of
which requires the aid of the most powerful telescopes, but it is much to k=
now where
that unfinished creation lies, and to see it, even though diminished by
distance to a mere speck of light.
Turn your glass upon the star shown in the map
just above Mu ([mu]) and Epsilon ([epsilon]). You will find an attractive
arrangement of small stars in its neighborhood. The star marked 104 is doub=
le
to the naked eye, and the row of stars below it is well worth looking at. T=
he
star Delta ([delta]) indicates the place where, in 1756, Tobias Mayer narro=
wly
escaped making a discovery that would have anticipated that which a quarter=
of
a century later made the name of Sir William Herschel world-renowned. The
planet Uranus passed near Delta in 1756, and Tobias Mayer saw it, but it mo=
ved
so slowly that he took it for a fixed star, never suspecting that his eyes =
had
rested upon a member of the solar system whose existence was, up to that ti=
me,
unknown to the inhabitants of Adam's planet.
Above Aquarius you will find the constellation
Pegasus. It is conspicuously marked by four stars of about the second
magnitude, which shine at the corners of a large square, called the Great
Square of Pegasus. This figure is some fifteen degrees square, and at once =
attracts
the eye, there being few stars visible within the quadrilateral, and no lar=
ge
ones in the immediate neighborhood to distract attention from it. One of the
four stars, however, as will be seen by consulting Map 15, does not belong =
to
Pegasus, but to the constellation Andromeda. Mythologically, this constella=
tion
represents the celebrated winged horse of antiquity:
&quo=
t;Now
heaven his further wandering flight confines, Where, splendid with his numerous stars=
, he
shines."
The star Alpha ([alpha]) is called Markab; Beta
([beta]) is Scheat, and Gamma ([gamma]) is Algenib; the fourth star in the
square, belonging to Andromeda, is called Alpheratz. Although Pegasus prese=
nts
a striking appearance to the unassisted eye, on account of its great square=
, it
contains little to attract the observer with an opera-glass. It will prove
interesting, however, to sweep with the glass carefully over the space with=
in
the square, which is comparatively barren to the naked eye, but in which ma=
ny
small stars will be revealed, of whose existence the naked-eye observer wou=
ld
be unaware. The star marked Pi ([pi]) is an interesting double, which can be
separated by a good eye without artificial aid, and which, with an opera-gl=
ass,
presents a fine appearance.
And now we come to Map No. 16, representing the
constellations Cetus, Pisces, Aries, and the Triangles. In consulting it the
observer is supposed to face the southeast. Cetus is a very large
constellation, and from the peculiar conformation of its principal stars it=
can
be readily recognized. The head is to the east, the star Alpha ([alpha]),
called Menkar, being in the nose of this imaginary inhabitant of the sky-de=
pths.
The constellation is supposed to represent the monster that, according to
fable, was sent by Neptune to devour the fair Andromeda, but whose bloodthi=
rsty
design was happily and gallantly frustrated by Perseus, as we shall learn f=
rom
starry mythology further on.
Although bearing the name Cetus, the Whale, the
pictures of the constellation in the old maps do not present us with the fo=
rm
of a whale, but that of a most extraordinary scaly creature with enormous j=
aws
filled with large teeth, a forked tongue, fore-paws armed with gigantic cla=
ws,
and a long, crooked, and dangerous-looking tail. Indeed, Aratus does not ca=
ll
it a "whale," but a "sea-monster," and Dr. Seiss would =
have
us believe that it was intended to represent the leviathan, whose terrible
prowess is celebrated in the book of Job.
By far the most interesting object in Cetus is=
the
star Mira. This is a famous variable--a sun that sometimes shines a thousan=
d-fold
more brilliantly than at others! It changes from the second magnitude to th=
e ninth
or tenth, its period from maximum to maximum being about eleven months. Dur=
ing
about five months of that time it is completely invisible to the naked eye;
then it begins to appear again, slowly increasing in brightness for some th=
ree
months, until it shines as a star of the second magnitude, being then as br=
ight
as, if not brighter than, the most brilliant stars in the constellation. It
retains this brilliance for about two weeks, and then begins to fade again,
and, within three months, once more disappears. There are various
irregularities in its changes, which render its exact period somewhat
uncertain, and it does not always attain the same degree of brightness at i=
ts
maximum. For instance, in 1779, Mira was almost equal in brilliance to a fi=
rst-magnitude
star, but frequently at its greatest brightness it is hardly equal to an
ordinary star of the second magnitude. By the aid of our little map you will
readily be able to find it. You will perceive that it has a slightly reddish
tint. Watch it from one of its maxima, and you will see it gradually fade f=
rom
sight until, at last, only the blackness of the empty sky appears where, a =
few
months before, a conspicuous star was visible. Keep watch of that spot, and=
in
due course you will perceive Mira shining there again--a mere speck, but sl=
owly
brightening--and in three months more the wonderful star will blaze again w=
ith
renewed splendor.
Knowing that our own sun is a variable
star--though variable only to a slight degree, its variability being due to=
the
spots that appear upon its surface in a period of about eleven years--we
possess some light that may be cast upon the mystery of Mira's variations. =
It
seems not improbable that, in the case of Mira, the surface of the star at =
the maximum
of spottedness is covered to an enormously greater extent than occurs during
our own sun-spot maxima, so that the light of the star, instead of being me=
rely
dimmed to an almost imperceptible extent, as with our sun, is almost blotted
out. When the star blazes with unwonted splendor, as in 1779, we may fairly
assume that the pent-up forces of this perishing sun have burst forth, as i=
n a
desperate struggle against extinction. But nothing can prevail against the
slow, remorseless, unswerving progress of that obscuration, which comes from
the leaking away of the solar heat, and which constitutes what we may call =
the
death of a sun. And that word seems peculiarly appropriate to describe the =
end of
a body which, during its period of visible existence, not only presents the
highest type of physical activity, but is the parent and supporter of all f=
orms
of life upon the planets that surround it.
We might even go so far as to say that possibly
Mira presents to us an example of what our sun will be in the course of tim=
e,
as the dead and barren moon shows us, as in a magician's glass, the approac=
hing
fate of the earth. Fortunately, human life is a mere span in comparison with
the æons of cosmic existence, and so we need have no fear that either we or=
our
descendants for thousands of generations shall have to play the tragic rôle=
of
Campbell's "Last Man," and endeavor to keep up a stout heart amid=
the
crash of time by meanly boasting to the perishing sun, whose rays have nurt=
ured
us, that, though his proud race is ended, we have confident anticipations of
immortality. I trust that, when man makes his exit from this terrestrial st=
age,
it will not be in the contemptible act of kicking a fallen benefactor.
There are several other variable stars in Cetu=
s,
but none possessing much interest for us. The observer should look at the g=
roup
of stars in the head, where he will find some interesting combinations, and
also at Chi, which is the little star shown in the map near Zeta ([zeta]). =
This
is a double that will serve as a very good test of eye and instrument, the
smaller companion-star being of only seven and a half magnitude.
Directly above Cetus is the long, straggling
constellation of Pisces, the Fishes. The Northern Fish is represented by the
group of stars near Andromeda and the Triangles. A long band or ribbon,
supposed to bind the fish together, trends thence first southeast and then =
west
until it joins a group of stars under Pegasus, which represents the Western
Fish, not to be confounded with the Southern Fish described near the beginn=
ing
of this chapter, which is a separate constellation. Fable has, however,
somewhat confounded these fishes; for while, as I have remarked above, the
Southern Fish is said to represent Venus after she had turned herself into a
fish to escape from the giant Typhon, the two fishes of the constellation we
are now dealing with are also fabled to represent Venus and her interesting=
son
Cupid under the same disguise assumed on precisely the same occasion. If
Typhon, however, was so great a brute that even Cupid's arrows were of no a=
vail
against him, we should, perhaps, excuse mythology for duplicating the recor=
d of
so wondrous an event.
You will find it very interesting to take your=
glass
and, beginning with the attractive little group in the Northern Fish, follow
the windings of the ribbon, with its wealth of tiny stars, to the Western F=
ish.
When you have arrived at that point, sweep well over the sky in that neighb=
orhood,
and particularly around and under the stars Iota ([iota]), Theta ([theta]),
Lambda ([lambda]), and Kappa ([kappa]). If you are using a powerful glass, =
you
will be surprised and delighted by what you see. Below the star Omega
([omega]), and to the left of Lambda, is the place which the sun occupies at
the time of the spring equinox--in other words, one of the two crossing-pla=
ces
of the equinoctial or the equator of the heavens, and the ecliptic, or the
sun's path. The prime meridian of the heavens passes through this point. You
can trace out this great circle, from which astronomical longitudes are
reckoned, by drawing an imaginary line from the equinoctial point just
indicated through [alpha] in Andromeda and [beta] in Cassiopeia to the
pole-star.
To the left of Pisces, and above the head of
Cetus, is the constellation Aries, or the Ram. Two pretty bright stars, four
degrees apart, one of which has a fainter star near it, mark it out plainly=
to
the eye. These stars are in the head of the Ram. The brightest one, Alpha (=
[alpha]),
is called Hamal; Beta ([beta]) is named Sheratan; and its fainter neighbor =
is
Mesarthim. According to fable, this constellation represents the ram that w=
ore
the golden fleece, which was the object of the celebrated expedition of the
Argonauts. There is not much in the constellation to interest us, except its
historical importance, as it was more than two thousand years ago the leadi=
ng
constellation of the zodiac, and still stands first in the list of the zodi=
acal
signs. Owing to the precession of the equinoxes, however, the vernal
equinoctial point, which was formerly in this constellation, has now advanc=
ed
into the constellation Pisces, as we saw above. Gamma ([gamma]), Arietis, is
interesting as the first telescopic double star ever discovered. Its duplic=
ity
was detected by Dr. Hooke while watching the passage of a comet near the st=
ar
in 1664. Singularly enough, the brightest star in the constellation, now be=
aring
the letter [alpha], originally did not belong to the constellation. Tycho B=
rahe
finally placed it in the head of Aries.
The little constellation of the Triangles, just
above Aries, is worth only a passing notice. Insignificant as it appears, t=
his
little group is a very ancient constellation. It received its name, Deltoto=
n,
from the Greek letter [Delta].
The reader must now be introduced to the
"Royal Family." Although the story of Perseus and Andromeda is, of
course, well known to nearly all readers, yet, on account of the great beau=
ty
and brilliancy of the group of constellations that perpetuate the memory of=
it
among the stars, it is worth recalling here. It will be remembered that, as
Perseus was returning through the air from his conquest of the Gorgon Medus=
a,
he saw the beautiful Andromeda chained to a rock on the sea-coast, waiting =
to be
devoured by a sea-monster. The poor girl's only offense was that her mother,
Cassiopeia, had boasted for her that she was fairer than the sea-beauty,
Atergatis, and for this Neptune had decreed that all the land of the Ethiop=
ians
should be drowned and destroyed unless Andromeda was delivered up as a
sacrifice to the dreadful sea-monster. When Perseus, dropping down to learn=
why
this maiden was chained to the rocks, heard from Andromeda's lips the story=
of
her woes, he laughed with joy. Here was an adventure just to his liking, and
besides, unlike his previous adventures, it involved the fate of a beautiful
woman with whom he was already in love. Could he save her? Well, wouldn't h=
e!
The sea-monster might frighten a kingdom full of Ethiops, but it could not =
shake
the nerves of a hero from Greece. He whispered words of encouragement to
Andromeda, who could scarce believe the good news that a champion had come =
to
defend her after all her friends and royal relations had deserted her. Neit=
her
could she feel much confidence in her young champion's powers when suddenly=
her
horrified gaze met the awful leviathan of the deep advancing to his feast! =
But
Perseus, with a warning to Andromeda not to look at what he was about to do,
sprang with his winged sandals up into the air. And then, as Charles Kingsl=
ey
has so beautifully told the story--
"On came the great sea-monster, coasting
along like a huge black galley, lazily breasting the ripple, and stopping at
times by creek or headland to watch for the laughter of girls at their
bleaching, or cattle pawing on the sand-hills, or boys bathing on the beach.
His great sides were fringed with clustering shells and sea-weeds, and the
water gurgled in and out of his wide jaws as he rolled along, dripping and
glistening in the beams of the morning sun. At last he saw Andromeda, and s=
hot
forward to take his prey, while the waves foamed white behind him, and befo=
re him
the fish fled leaping.
"Then down from the height of the air fell
Perseus like a shooting-star--down to the crest of the waves, while Androme=
da
hid her face as he shouted. And then there was silence for a while.
"At last she looked up trembling, and saw
Perseus springing toward her; and, instead of the monster, a long, black ro=
ck,
with the sea rippling quietly round it."
Perseus had turned the monster into stone by
holding the blood-freezing head of Medusa before his eyes; and it was fear =
lest
Andromeda herself might see the Gorgon's head, and suffer the fate of all w=
ho
looked upon it, that had led him to forbid her watching him when he attacked
her enemy. Afterward he married her, and Cassiopeia, Andromeda's mother, an=
d Cepheus,
her father, gave their daughter's rescuer a royal welcome, and all the Ethi=
ops
rose up and blessed him for ridding the land of the monster. And now, if we
choose, we can, any fair night, see the principal characters of this old
romance shining in starry garb in the sky. Aratus saw them there in his day,
more than two hundred years before Christ, and has left this description in=
his
"Skies," as translated by Poste:
&quo=
t;Nor
shall blank silence whelm the harassed house Of Cepheus; the high heavens know their=
name,
For Zeus is in their line at few
removes. Cepheus himself by She-b=
ear
Cynosure, Iasid king stands with
uplifted arms. From his belt thou
castest not a glance To see the f=
irst
spire of the mighty Dragon.
"Eastward from him, heaven-troubled queen, with scanty stars But lustrous in the full-mooned night, =
sits
Cassiopeia. Not numerous nor
double-rowed The gems that deck h=
er
form, But like a key which throug=
h an
inward-fastened Folding-door men =
thrust
to knock aside the bolts, They sh=
ine in
single zigzag row. She, too, o'er
narrow shoulders stretching Uplif=
ted
hands, seems wailing for her child.
&quo=
t;For
there, a woful statue-form, is seen Andromeda, parted from her mother's sid=
e.
Long I trow Thou wilt not seek he=
r in
the nightly sky, So bright her he=
ad, so
bright Her shoulders, feet, and g=
irdle.
Yet even there she has her arms
extended, And shackled even in he=
aven;
uplifted, Outspread eternally are=
those
fair hands.
&quo=
t;Her
feet point to her bridegroom Pers=
eus,
on whose shoulder they rest. He i=
n the
north-wind stands gigantic, His r=
ight
hand stretched toward the throne =
Where
sits the mother of his bride. As one bent on some high deed, Dust-stained he strides over the floor =
of
heaven."
The makers of old star-maps seem to have vied =
in
the effort to represent with effect the figures of Andromeda, Perseus, and
Cassiopeia among the stars, and it must be admitted that some of them succe=
eded
in giving no small degree of life and spirit to their sketches.
The starry riches of these constellations are =
well
matched with their high mythological repute. Lying in and near the Milky-Wa=
y,
they are particularly interesting to the observer with an opera-glass. Besi=
des,
they include several of the most celebrated wonders of the firmament.
In consulting Map No. 17, the observer is supp=
osed
to face the east and northeast. We will begin our survey with Andromeda. The
three chief stars of this constellation are of the second magnitude, and li=
e in
a long, bending row, beginning with Alpha ([alpha]), or Alpheratz, in the h=
ead,
which, as we have seen, marks one corner of the great Square of Pegasus. Be=
ta
([beta]), or Mirach, with the smaller stars Mu ([mu]) and Nu ([nu]), form t=
he
girdle. The third of the chief stars is Gamma ([gamma]), or Almaach, situat=
ed
in the left foot. The little group of stars designated Lambda ([lambda]), K=
appa
([kappa]), and Iota ([iota]), mark the extended right hand chained to the r=
ock,
and Zeta ([zeta]) and some smaller stars southwest of it show the left arm =
and
hand, also stretched forth and shackled.
In searching for picturesque objects in Androm=
eda,
begin with Alpheratz and the groups forming the hands. Below the girdle wil=
l be
seen a rather remarkable arrangement of small stars in the mouth of the
Northern Fish. Now follow up the line of the girdle to the star Nu ([nu]). =
If
your glass has a pretty wide field, your eye will immediately catch the gli=
mmer
of the Great Nebula of Andromeda in the same field with the star. This is t=
he
oldest or earliest discovered of the nebulæ, and, with the exception of tha=
t in
Orion, is the grandest visible in this hemisphere. Of course, not much can =
be
expected of an opera-glass in viewing such an object; and yet a good glass,=
in
clear weather and the absence of the moon, makes a very attractive spectacl=
e of
it.
By turning the eyes aside, the nebula can be s=
een,
extended as a faint, wispy light, much elongated on either side of the brig=
hter
nucleus. The cut here given shows, approximately, the appearance of the neb=
ula,
together with some of the small stars in its neighborhood, as seen with a
field-glass. With large telescopes it appears both larger and broader, expa=
nding
to a truly enormous extent, and in Bond's celebrated picture of it we behold
gigantic rifts running lengthwise, while the whole field of sky in which it=
is
contained appears sprinkled over with minute stars apparently between us and
the nebula. It was in, or, probably more properly speaking, in line with, t=
his
nebula that a new star suddenly shone out in 1885, and, after flickering and
fading for a few months, disappeared. That the outburst of light in this st=
ar
had any real connection with the nebula is exceedingly improbable. Although=
it appeared
to be close beside the bright nucleus of the nebula, it is likely that it w=
as
really hundreds or thousands of millions of miles either this side or the o=
ther
side of it. Why it should suddenly have blazed into visibility, and then in=
so
short a time have disappeared, is a question as difficult as it is interest=
ing.
The easiest way to account for it, if not the most satisfactory, is to assu=
me
that it is a variable star of long period, and possessing a very wide range=
of
variability. One significant fact that would seem to point to some connecti=
on
between star and the nebula, after all, is that a similar occurrence was
noticed in the constellation Scorpio in 1860, and to which I have previousl=
y referred
(see Chapter II). In that case a faint star projected against the backgroun=
d of
a nebula, suddenly flamed into comparatively great brilliance, and then fad=
ed
again. The chances against the accidental superposition of a variable star =
of
such extreme variability upon a known nebula occurring twice are so great t=
hat,
for that reason alone, we might be justified in thinking some mysterious ca=
usal
relation must in each case exist between the nebula and the star. The
temptation to indulge in speculation is very great here, but it is better to
wait for more light, and confess that for the present these things are inex=
plicable.
It will be found very interesting to sweep with
the glass slowly from side to side over Andromeda, gradually approaching to=
ward
Cassiopeia or Perseus. The increase in the richness of the stratum of faint
stars that apparently forms the background of the sky will be clearly
discernible as you approach the Milky-Way, which passes directly through
Cassiopeia and Perseus. It may be remarked that the Milky-Way itself, in th=
at splendidly
rich region about Sagittarius (described in the "Stars of Summer"=
),
is not nearly so effective an object with an opera-glass as it is above Cyg=
nus
and in the region with which we are now dealing. This seems to be owing to =
the
smaller magnitude of its component stars in the southern part of the stream.
There the background appears more truly "milky," while in the
northern region the little stars shine distinct, like diamond-specks, on a
black background.
The star Nu, which serves as a pointer to the
Great Nebula, is itself worth some attention with a pretty strong glass on
account of a pair of small stars near it.
The star Gamma ([gamma]) is interesting, not o=
nly
as one of the most beautiful triples in the heavens (an opera-glass is far =
too
feeble an instrument to reveal its companions), but because it serves to
indicate the radiant point of the Biela meteors. There was once a comet wel=
l known
to astronomers by the name of its discoverer, Biela. It repeated its visits=
to
the neighborhood of the sun once in every six or seven years. In 1846 this
comet astonished all observers by splitting into two comets, which continue=
d to
run side by side, like two equal racers, in their course around the sun. Ea=
ch
developed a tail of its own. In 1852, when the twin comets were due again, =
the
astronomical world was on the qui vive, and they did not disappoint
expectation, for back they came out of the depths of space, still racing, b=
ut
much farther apart than they had been before, alternating in brightness as =
if
the long struggle had nearly exhausted them, and finally, like spent runner=
s,
growing faint and disappearing. They have never been seen since.
In 1872, when the comets should have been visi=
ble,
if they still existed, a very startling thing happened. Out of the northern
heavens, along the track of the missing comets, where the earth crossed it,=
on the
night of the 27th of November came glistening and dashing the fiery spray o=
f a
storm of meteors. It was the dust and fragments of the lost comet of Biela,
which, after being split in two in 1852, had evidently continued the proces=
s of
disintegration until its cometary character was completely lost. It seems to
have made a truly ghostly exit, for right after the meteor swarm of 1872 a
mysterious cometary body was seen, which was supposed at the time to be the
missing comet itself, and which, it is not altogether improbable, may have =
been
a fragment of it. Three days after the meteors burst over Europe, it occurr=
ed
to Professor Klinkerfues, of Berlin, that if they came from Biela's comet t=
he
comet itself ought to be seen in the southern hemisphere retreating from it=
s encounter
with the earth. On November 30th he sent his now historical telegram to Mr.
Pogson, an astronomer at Madras; "Biela touched earth November 27th.
Search near Theta Centauri." For thirty-six hours after the receipt of
this extraordinary request Mr. Pogson was prevented by clouds from scanning=
the
heavens with his telescope. When the sky cleared at last, behold there was a
comet in the place indicated in the telegram! It was glimpsed again the next
night, and then clouds intervened, and not a trace of it was ever seen
afterward.
But every year, on the 27th of November, when =
the
earth crosses the orbit of the lost comet, meteoric fragments come plunging
into our atmosphere, burning as they fly. Ordinarily their number is small,=
but
when, as in 1872, a swarm of the meteors is in that part of their orbit whi=
ch
the earth crosses, there is a brilliant spectacle. In 1885 this occurred, a=
nd
the world was treated to one of the most splendid meteoric displays on reco=
rd.
Next let us turn to Perseus. The bending row of
stars marking the center of this constellation is very striking and brillia=
nt.
The brightest star in the constellation is Alpha, or Algenib, in the center=
of
the row. The head of Perseus is toward Cassiopeia, and in his left hand he
grasps the head of Medusa, which hangs down in such a way that its principal
star Beta, or Algol, forms a right angle with Algenib and Almaach in Androm=
eda.
This star Algol, or the Demon, as the Arabs call it, is in some respects the
most wonderful and interesting in all the heavens. It is as famous for the
variability of its light as Mira, but it differs widely from that star both=
in
its period, which is very short, and in the extent of the changes it underg=
oes.
During about two days and a half, Algol is equal in brilliance to Algenib,
which is a second-magnitude star; then it begins to fade, and in the course=
of about
four and a half hours it sinks to the fourth magnitude, being then about eq=
ual
to the faint stars near it. It remains thus obscured for only a few minutes,
and then begins to brighten again, and in about four and a half hours more
resumes its former brilliance. This phenomenon is very easily observed, for=
, as
will be seen by consulting our little map, Algol can be readily found, and =
its
changes are so rapid that under favorable circumstances it can be seen in t=
he
course of a single night to run through the whole gamut. Of course, no opti=
cal
instrument whatever is needed to enable one to see these changes of Algol, =
for
it is plainly visible to the naked eye throughout, but it will be found int=
eresting
to watch the star with an opera-glass. Its periodic time from minimum to mi=
nimum
is two days, twenty hours, and forty-nine minutes, lacking a few seconds. A=
ny
one can calculate future minima for himself by adding the periodic time abo=
ve
given to the time of any observed minimum.
While spots upon its surface may be the cause =
of
the variations in the light of Mira, it is believed that the more rapid cha=
nges
of Algol may be due to another cause; namely, the existence of a huge, dark
body revolving swiftly around it at close quarters in an orbit whose plane =
is directed
edgewise toward the earth, so that at regular intervals this dark body caus=
es a
partial eclipse of Algol. Notwithstanding the attacks that have been made u=
pon
this theory, it seems to hold its ground, and it will probably continue to =
find
favor as a working hypothesis until some fresh light is cast upon the probl=
em.
It hardly needs to be said that the dark body in question, if it exists, mu=
st
be of enormous size, bearing no such insignificant proportion to the size of
Algol as the earth does to the sun, but being rather the rival in bulk of i=
ts
shining brother--a blind companion, an extinguished sun.
There was certainly great fitness in the selec=
tion
of the little group of stars of which this mysterious Algol forms the most
conspicuous member, to represent the awful head of the Gorgon carried by th=
e victorious
Perseus for the confusion of his enemies. In a darker age than ours the win=
king
of this demon-star must have seemed a prodigy of sinister import.
Turn now to the bright star Algenib, or Alpha
Persei. You will find with the glass an exceedingly attractive spectacle th=
ere.
In my note-book I find this entry, made while sweeping over Perseus for
materials for this chapter: "The field about Alpha is one of the fines=
t in
the sky for an opera-glass. Stars conspicuously ranged in curving lines and
streams. A host follows Alpha from the east and south." The picture on
page 84 will give the reader some notion of the exceeding beauty of this fi=
eld
of stars, and of the singular manner in which they are grouped, as it were,=
behind
their leader. A field-glass increases the beauty of the scene.
The reader will find a starry cluster marked on
Map 17 as the "Great Cluster." This object can be easily detected=
by
the naked eye, resembling a wisp of luminous cloud. It marks the hand in wh=
ich
Perseus clasps his diamond sword, and, with a telescope of medium power, it=
is one
of the most marvelously beautiful objects in the sky--a double swarm of sta=
rs,
bright enough to be clearly distinguished from one another, and yet so nume=
rous
as to dazzle the eye with their lively beams. An opera-glass does not posse=
ss
sufficient power to "resolve" this cluster, but it gives a startl=
ing
suggestion of its half-hidden magnificence, and the observer will be likely=
to
turn to it again and again with increasing admiration. Sweep from this to A=
lpha
Persei and beyond to get an idea of the procession of suns in the Milky-Way.
The nebulous-looking cluster marked 34 M appears with an opera-glass like a
faint comet.
About a thousand years ago the theologians und=
ertook
to reconstruct the constellation figures, and to give them a religious
significance. They divided the zodiac up among the twelve apostles, St. Pet=
er
taking the place of Aries, with the Triangles for his mitre. In this
reconstruction Perseus was transmogrified into St. Paul, armed with a sword=
in
one hand and a book in the other; Cassiopeia became Mary Magdalene; while p=
oor Andromeda,
stripped of all her beauty and romance, was turned into a sepulchre!
Next look at Cassiopeia, which is distinctly m=
arked
out by the zigzag row of stars so well described by Aratus. Here the Milky-=
Way
is so rich that the observer hardly needs any guidance; he is sure to stumb=
le
upon interesting sights for himself. The five brightest stars are generally=
represented
as indicating the outlines of the chair or throne in which the queen sits, =
the
star Zeta ([zeta]) being in her head. Look at Zeta with a good field-glass,=
and
you will see a singular and brilliant array of stars near it in a broken
half-circle, which may suggest the notion of a crown. Near the little star
Kappa ([kappa]) in the map will be seen a small circle and the figures 1572.
This shows the spot where the famous temporary star, which has of late been
frequently referred to as the "Star of Bethlehem," appeared. It w=
as
seen in 1572, and carefully observed by the famous astronomer Tycho Brahe. =
It
seems to have suddenly burst forth with a brilliance that outshone every ot=
her
star in the heavens, not excepting Sirius itself. But its supremacy was
short-lived. In a few months it had sunk to the second magnitude. It contin=
ued
to grow fainter, exhibiting some remarkable changes of color in the mean ti=
me,
and in less than a year and a half it disappeared. It has never been seen
since. But in 1264, and again in 945, a star is said to have suddenly blazed
out near that point in the heavens. There is no certainty about these earli=
er
apparitions, but, assuming that they are not apocryphal, they might possibly
indicate that the star seen by Tycho was a periodical one, its period
considerably exceeding three hundred years. Carrying this supposed period b=
ack,
it was found that an apparition of this star might have occurred about the =
time
of the birth of Christ. It did not require a very prolific imagination to
suggest its identity with the so-called star of the Magi, and hence the leg=
end
of the Star of Bethlehem and its impending reappearance, of which we have h=
eard
so much of late. It will be observed, from the dates given above, that, even
supposing them to be correct, no definite period is indicated for the
reappearance of the star. In one case the interval is three hundred and eig=
ht
years, and in the other three hundred and nineteen years. In short, there a=
re
too many suppositions and assumptions involved to allow of any credence bei=
ng
given to the theory of the periodicity of Tycho's wonderful star. At the sa=
me
time, nobody can say it is impossible that the star should appear again, an=
d so
it may be interesting for the reader to know where to look for it.
Many of the most beautiful sights of this sple=
ndid
constellation are beyond the reach of an opera-glass, and reserved for the
grander powers of the telescope.
We will pause but briefly with Cepheus, for the
old king's constellation is comparatively dim in the heavens, as his part in
the dramatic story of Andromeda was contemptible, and he seems to have got
among the stars only by virtue of his relationship to more interesting pers=
ons.
He does possess one gem of singular beauty--the star Mu, which may be found=
about
two and a half degrees south of the star Nu ([nu]). It is the so-called
"Garnet Star," thus named by William Herschel, who advises the ob=
server,
in order to appreciate its color, to glance from it to Alpha Cephei, which =
is a
white star. Mu is variable, changing from the fourth to the sixth magnitude=
in
a long period of five or six years. Its color is changeable, like its light.
Sometimes it is of a deep garnet hue, and at other times it is orange-color=
ed.
Upon the whole, it appears of a deeper red than any other star visible to t=
he
naked eye.
If you have a good field-glass, try its powers
upon the star Delta ([delta]) Cephei. This is a double star, the components
being about forty-one seconds of arc apart, the larger of four and one half=
magnitude,
and the smaller of the seventh magnitude. The latter is of a beautiful blue
color, while the larger star is yellow or orange. With a good eye, a steady
hand, and a clear glass, magnifying not less than six diameters, you can
separate them, and catch the contrasted tints of their light. Besides being=
a
double star, Delta is variable.
I have
never beheld the first indications of the rising of Orion without a peculiar
feeling of awakened expectation, like that of one who sees the curtain rise
upon a drama of absorbing interest. And certainly the magnificent company of
the winter constellations, of which Orion is the chief, make their entrance
upon the scene in a manner that may be described as almost dramatic. First =
in
the east come the world-renowned Pleiades. At about the same time Capella, =
one
of the most beautiful of stars, is seen flashing above the northeastern
horizon. These are the sparkling ushers to the coming spectacle. In an hour=
the
fiery gleam of Aldebaran appears at the edge of the dome below the Pleiades=
, a
star noticeable among a thousand for its color alone, besides being one of =
the
brightest of the heavenly host. The observer familiar with the constellatio=
ns
knows, when he sees this red star which marks the eye of the angry bull,
Taurus, that just behind the horizon stands Orion with starry shield and
upraised club to meet the charge of his gigantic enemy. With Aldebaran rises
the beautiful V-shaped group of the Hyades. Presently the star-streams of
Eridanus begin to appear in the east and southeast, the immediate precursor=
s of
the rising of Orion:
&quo=
t;And
now the river-flood's first winding reach The becalmed mariner may see in heaven,=
As he watches for Orion to espy if he h=
ath
aught to say Of the night's measu=
re or
the slumbering winds."
The first glimpse we get of the hero of the sk=
y is
the long bending row of little stars that glitter in the lion's skin which,
according to mythology, serves him for a shield. The great constellation th=
en advances
majestically into sight. First of its principal stars appears Bellatrix in =
the
left shoulder; then the little group forming the head, followed closely by =
the
splendid Betelgeuse, "the martial star," flashing like a decorati=
on
upon the hero's right shoulder. Then come into view the equally beautiful R=
igel
in the left foot, and the striking row of three bright stars forming the Be=
lt.
Below these hangs another starry pendant marking the famous sword of Orion,=
and
last of all appears Saiph in the right knee. There is no other constellatio=
n containing
so many bright stars. It has two of the first magnitude, Betelgeuse and Rig=
el;
the three stars in the Belt, and Bellatrix in the left shoulder, are all of=
the
second magnitude; and besides these there are three stars of the third magn=
itude,
more than a dozen of the fourth, and innumerable twinklers of smaller
magnitudes, whose commingled scintillations form a celestial illumination of
singular splendor.
&quo=
t;Thus
graced and armed he leads the starry host."
By the time Orion has chased the Bull half-way=
up
the eastern slope of the firmament, the peerless Dog-Star, Sirius, is flami=
ng
at the edge of the horizon, while farther north glitters Procyon, the little
Dog-Star, and still higher are seen the twin stars in Gemini. When these co=
nstellations
have advanced well toward the meridian, as shown in our circular map, their
united radiance forms a scene never to be forgotten. Counting one of the st=
ars
in Gemini as of the first rank, there are no less than seven first-magnitude
stars ranged around one another in a way that can not fail to attract the
attention and the admiration of the most careless observer. Aldebaran, Cape=
lla,
the Twins, Procyon, Sirius, and Rigel mark the angles of a huge hexagon, wh=
ile
Betelgeuse shines with ruddy beauty not far from the center of the figure. =
The
heavens contain no other naked-eye view comparable with this great array, n=
ot even
the glorious celestial region where the Southern Cross shines supreme, being
equal to it in splendor.
As an offset to the discomforts of winter
observations of the stars, the observer finds that the softer skies of summ=
er
have no such marvelous brilliants to dazzle his eyes as those that illumine=
the
hyemal heavens. To comprehend the real glories of the celestial sphere in t=
he
depth of winter one should spend a few clear nights in the rural districts =
of
New York or New England, when the hills, clad with sparkling blankets of cr=
usted
snow, reflect the glitter of the living sky. In the pure frosty air the sta=
rs
seem splintered and multiplied indefinitely, and the brighter ones shine wi=
th a
splendor of light and color unknown to the denizen of the smoky city, whose
eyes are dulled and blinded by the glare of streetlights. There one may det=
ect
the delicate shade of green that lurks in the imperial blaze of Sirius, the
beautiful rose-red light of Aldebaran, the rich orange hue of Betelgeuse, t=
he
blue-white radiance of Rigel, and the pearly luster of Capella. If you have
never seen the starry heavens except as they appear from city streets and s=
quares,
then, I had almost said, you have never seen them at all, and especially in=
the
winter is this true. I wish I could describe to you the impression that they
can make upon the opening mind of a country boy, who, knowing as yet nothin=
g of
the little great world around him, stands in the yawning silence of night a=
nd
beholds the illimitably great world above him, looking deeper than thought =
can
go into the shining vistas of the universe, and overwhelmed with the wonder=
of
those marshaled suns.
Looking now at Map 18, we see the heavens as t=
hey
appear at midnight on the 1st of December, at 10 o'clock P. M. on the 1st of
January, and at 8 o'clock P. M. on the 1st of February. In the western half=
of
the sky we recognize Andromeda, Pegasus, Pisces, Cetus, Aries, Cassiopeia, =
and other
constellations that we studied in the "Stars of Autumn." Far over=
in
the east we see rising Leo, Cancer, and Hydra, which we included among the
"Stars of Spring." Occupying most of the southern and eastern hea=
vens
are the constellations which we are now to describe under the name of the
"Stars of Winter," because in that season they are seen under the
most favorable circumstances. I have already referred to the admirable way =
in
which the principal stars of some of these constellations are ranged round =
one
another. By the aid of the map the observer can perceive the relative posit=
ion
of the different constellations, and, having fixed this in his mind, he wil=
l be
prepared to study them in detail.
Let us now begin with Map No. 19, which shows =
us
the constellations of Eridanus, Lepus, Orion, and Taurus. Eridanus is a lar=
ge
though not very conspicuous constellation, which is generally supposed to
represent the celebrated river now known as the Po. It has had different na=
mes
among different peoples, but the idea of a river, suggested by its long, wi=
nding
streams of stars, has always been preserved. According to fable, it is the
river into which Phaeton fell after his disastrous attempt to drive the cha=
riot
of the sun for his father Phoebus, and in which hare-brained adventure he
narrowly missed burning the world up. The imaginary river starts from the
brilliant star Rigel, in the left foot of Orion, and flows in a broad upward
bend toward the west; then it turns in a southerly direction until it reach=
es
the bright star Gamma ([gamma]), where it bends sharply to the north, and t=
hen
quickly sweeps off to the west once more, until it meets the group of stars
marking the head of Cetus. Thence it runs south, gradually turning eastward,
until it flows back more than half-way to Orion. Finally it curves south ag=
ain and
disappears beneath the horizon. Throughout the whole distance of more than =
100°
the course of the stream is marked by rows of stars, and can be recognized
without difficulty by the amateur observer.
The first thing to do with your opera-glass, a= fter you have fixed the general outlines of the constellation in your mind by naked-eye observations, is to sweep slowly over the whole course of the str= eam, beginning at Rigel, and following its various wanderings. Eridanus ends in = the southern hemisphere near a first-magnitude star called Achernar, which is situated in the stream, but can not be seen from our latitudes. Along the stream you will find many interesting groupings of the stars. In the map see the pair of stars below and to the right of Nu ([nu]). These are the two Omicrons, the upper one being [omicron]¹ and the lower one [omicron]². The latter is of an orange hue, and is remarkable for the speed with which it is flying through space. There are only one or two stars whose proper motion, = as it is called, is more rapid than that of [omicron]² in Eridanus. It changes= its place nearly seven minutes of arc in a century. The records of the earliest observations we possess show that near the beginning of the Christian era it was about half-way between [omicron]¹ and [nu]. Its companion [omicron]¹, on the contrary, seems to be almost stationary, so that [omicron]² will gradua= lly draw away from it, passing on toward the southwest until, in the course of centuries, it will become invisible from our latitudes. This flying star is accompanied by two minute companions, which in themselves form a close and = very delicate double star. These two little stars, of only 9.5 and 10.5 magnitud= e, respectively, are, of course beyond the ken of the observer with an opera-glass. The system of which they form a part, however, is intensely interesting, since the appearances indicate that they belong, in the manner= of satellites, to [omicron]², and are fellow-voyagers of that wonderful star.<= o:p>
Having admired the star-groups of Eridanus, on=
e of
the prettiest of which is to be seen around Beta ([beta]), let us turn next=
to
Taurus, just above or north of Eridanus. Two remarkable clusters at once
attract the eye, the Hyades, which are shaped somewhat like the letter [V],
with Aldebaran in the upper end of the left-hand branch, and the Pleiades, =
whose
silvery glittering has made them celebrated in all ages. The Pleiades are in
the shoulder and the Hyades in the face of Taurus, Aldebaran most appropria=
tely
representing one of his blazing eyes as he hurls himself against Orion. The
constellation-makers did not trouble themselves to make a complete Bull, and
only the head and fore-quarters of the animal are represented. If Taurus had
been completed on the scale on which he was begun, there would have been no
room in the sky for Aries; one of the Fishes would have had to abandon his
celestial swimming-place, and even the fair Andromeda would have found hers=
elf uncomfortably
situated. But, as if to make amends for neglecting to furnish their heavenly
Bull with hind-quarters, the ancients gave him a most prodigious and beauti=
ful
pair of horns, which make the beholder feel alarm for the safety of Orion.
Starting out of the head above the Hyades, as illustrated in our cut, the h=
orns
curve upward and to the east, each being tipped by a bright star. Along and
between the horns runs a scattered and broken stream of minute stars which =
seem
to be gathered into knots just beyond the end of the horns, where they dip =
into
the edge of the Milky-Way. Many of these stars can be seen, on a dark night,
with an ordinary opera-glass, but, to see them well, one should use as larg=
e a
field-glass as he can obtain. With such a glass their appearance almost mak=
es
one suspect that Virgil had a poetic prevision of the wonders yet to be
revealed by the telescope when he wrote, as rendered by Dryden, of the seas=
on--
&quo=
t;When
with his golden horns in full career The Bull beats down the barriers of the=
year."
Below the tips of the horns, and over Orion's
head, there are also rich clusters of stars, as if the Bull were flaunting
shreds of sparkling raiment torn from some celestial victim of his fury. Wi=
th
an ordinary glass, however, the observer will not find this star-sprinkled
region around the horns of Taurus as brilliant a spectacle as that presente=
d by
the Hyades and the group of stars just above them in the Bull's ear. The two
stars in the tips of the horns are both interesting, each in a different wa=
y. The
upper and brighter one of the two, marked Beta ([beta]) in Map No. 19, is
called El Nath. It is common to the left horn of Taurus and the right foot =
of
Auriga, who is represented standing just above. It is a singularly white st=
ar.
This quality of its light becomes conspicuous when it is looked at with a
glass. The most inexperienced observer will hardly fail to be impressed by =
the
pure whiteness of El Nath, in comparison with which he will find that many =
of
the stars he had supposed to be white show a decided tinge of color. The st=
ar
in the tip of the right or southern horn, Zeta ([zeta]), is remarkable, not=
on its
own account, but because it serves as a pointer to a famous nebula, the
discovery of which led Messier to form his catalogue of nebulæ. This is
sometimes called the "Crab Nebula," from the long sprays of nebul=
ous matter
which were seen surrounding it with Lord Rosse's great telescope. Our little
sketch is simply intended to enable the observer to locate this strange obj=
ect.
If he wishes to study its appearance, he must use a powerful telescope. But
with a first-rate field-glass he can see it as a speck of light in the posi=
tion
shown in the cut, where the large star is Zeta and the smaller ones are fai=
nt
stars, the relative position of which will enable the observer to find the
nebula, if he keeps in mind that the top of the cut is toward the north. It=
is
noteworthy that this nebula for a time deceived several of the watchers who
were on the lookout for the predicted return of Halley's comet in 1835.
And now let us look at the Hyades, an assembla=
ge
of stars not less beautiful than their more celebrated sisters the Pleiades.
The leader of the Hyades is Aldebaran, or Alpha Tauri, and his followers are
worthy of their leader. The inexperienced observer is certain to be surpris=
ed
by the display of stars which an opera-glass brings to view in the Hyades. =
Our
illustration will give some notion of their appearance with a large field-g=
lass.
The "brackish poet," of whose rhymes Admiral Smyth was so fond, t=
hus
describes the Hyades:
&quo=
t;In
lustrous dignity aloft see Alpha Tauri shine, The splendid zone he decorates attests =
the
Power divine: For mark around what
glitt'ring orbs attract the wandering eye, You'll soon confess no other star has s=
uch
attendants nigh."
The redness of the light of Aldebaran is a very
interesting phenomenon. Careful observation detects a decided difference
between its color and that of Betelgeuse, or Alpha Orionis, which is also a=
red
star. It differs, too, from the brilliant red star of summer, Antares.
Aldebaran has a trace of rose-color in its light, while Betelgeuse is of a =
very
deep orange, and Antares may be described as fire-red. These shades of color
can easily be detected by the naked eye after a little practice. First comp=
are
Aldebaran and Betelgeuse, and glance from each to the brilliant white, or
bluish-white, star Rigel in Orion's foot. Upon turning the eye back from Ri=
gel
to Aldebaran the peculiar color of the latter is readily perceived.
Spectroscopic analysis has revealed the presence in Aldebaran of hydrogen,
sodium, magnesium, calcium, iron, bismuth, tellurium, antimony, and mercury.
And so modern discoveries, while they have pushed back the stars to distanc=
es
of which the ancients could not conceive, have, at the same time, and equal=
ly,
widened the recognized boundaries of the physical universe and abolished
forever the ancient distinction between the heavens and the earth. It is a
plain road from the earth to the stars, though mortal feet can not tread it=
.
Keeping in mind that in our little picture of =
the
Hyades the top is north, the right hand west, and the left hand east, the
reader will be able to identify the principal stars in the group. Aldebaran=
is
readily recognized, because it is the largest of all. The bright star near =
the upper
edge of the picture is Epsilon Tauri, and its sister star, forming the poin=
t of
the [V], is Gamma Tauri. The three brightest stars between Epsilon and Gamm=
a,
forming a little group, are the Deltas, while the pair of stars surrounded =
by
many smaller ones, half-way between Aldebaran and Gamma, are the Thetas. Th=
ese
stars present a very pretty appearance, viewed with a good glass, the effect
being heightened by a contrast of color in the two Thetas. The little pair
southeast of Aldebaran, called the Sigmas, is also a beautiful object. The
distance apart of these stars is about seven minutes of arc, while the dist=
ance
between the two Thetas is about five and a half minutes of arc. These measu=
res
may be useful to the reader in estimating the distances between other stars
that he may observe. It will also be found an interesting test of the eye-s=
ight
to endeavor to see these stars as doubles without the aid of a glass. Perso=
ns
having keen eyes will be able to accomplish this.
North of the star Epsilon will be seen a little
group in the ear of the Bull (see cut, "The Golden Horns of Taurus&quo=
t;),
which presents a brilliant appearance with a small glass. The southernmost =
pair
in the group are the Kappas, whose distance apart is very nearly the same as
that of the Thetas, described above; but I think it improbable that anybody
could separate them with the naked eye, as there is a full magnitude betwee=
n them
in brightness, and the smaller star is only of magnitude 6.5, while sixth-m=
agnitude
stars are generally reckoned as the smallest that can be seen by the naked =
eye.
Above the Kappas, and in the same group in the ear, are the two Upsilons,
forming a wider pair.
Next we come to the Pleiades:
"Though small their size and pale their light, wide is their
fame."
In every age and in every country the Pleiades
have been watched, admired, and wondered at, for they are visible from every
inhabited land on the globe. To many they are popularly known as the Seven
Stars, although few persons can see more than six stars in the group with t=
he unaided
eye. It is a singular fact that many of the earliest writers declare that o=
nly
six Pleiades can be seen, although they all assert that they are seven in
number. These seven were the fabled daughters of Atlas, or the Atlantides,
whose names were Merope, Alcyone, Celæno, Electra, Taygeta, Asterope, and M=
aia.
One of the stories connected with them is that Merope married a mortal,
whereupon her star grew dim among her sisters. Another fable assures us that
Electra, unable to endure the sight of the burning of Troy, hid her face in=
her
hands, and so blotted her star from the sky. While we may smile at these
stories, we can not entirely disregard them, for they are intermingled with
some of the richest literary treasures of the world, and they come to us, l=
ike
some old keepsake, perfumed with the memory of a past age. The mythological=
history
of the Pleiades is intensely interesting, too, because it is world-wide. Th=
ey
have impressed their mark, in one way or another, upon the habits, customs,
traditions, language, and history of probably every nation. This is true of
savage tribes as well as of great empires. The Pleiades furnish one of the
principal links that appear to connect the beginnings of human history with
that wonderful prehistoric past, where, as through a gulf of mist, we seem =
to
perceive faintly the glow of a golden age beyond. The connection of the
Pleiades with traditions of the Flood is most remarkable. In almost every p=
art
of the world, and in various ages, the celebration of a feast or festival of
the dead, dimly connected by traditions with some great calamity to the hum=
an
race in the past, has been found to be directly related to the Pleiades. Th=
is festival
or rite, which has been discovered in various forms among the ancient Hindo=
os,
Egyptians, Persians, Peruvians, Mexicans, Druids, etc., occurs always in the
month of November, and is regulated by the culmination of the Pleiades. The
Egyptians directly connected this celebration with a deluge, and the Mexica=
ns,
at the time of the Spanish conquest, had a tradition that the world had once
been destroyed at the time of the midnight culmination of the Pleiades. Amo=
ng
the savages inhabiting Australia and the Pacific island groups a similar ri=
te
has been discovered. It has also been suggested that the Japanese feast of =
lanterns
is not improbably related to this world-wide observance of the Pleiades, as
commemorating some calamitous event in the far past which involved the whole
race of man in its effects.
The Pleiades also have a supposed connection w=
ith
that mystery of mysteries, the great Pyramid of Cheops. It has been found t=
hat
about the year 2170 B. C., when the beginning of spring coincided with the =
culmination
of the Pleiades at midnight, that wonderful group of stars was visible, jus=
t at
midnight, through the mysterious southward-pointing passage of the Pyramid.=
At
the same date the then pole-star, Alpha Draconis, was visible through the
northward-pointing passage of the Pyramid.
Another curious myth involving the Pleiades as=
a
part of the constellation Taurus is that which represents this constellatio=
n as
the Bull into which Jupiter changed himself when he carried the fair Europa=
away
from Phoenicia to the continent that now bears her name. In this story the =
fact
that only the head and fore-quarters of the Bull are visible in the sky is
accounted for on the ground that the remainder of his body is beneath the w=
ater
through which he is swimming. Here, then, is another apparent link with the
legends of the Flood, with which the Pleiades have been so strangely connec=
ted,
as by common consent among many nations, and in the most widely separated p=
arts
of the earth.
With the most powerful field-glass you may be =
able
to see all of the stars represented in our picture of the Pleiades. With an
ordinary opera-glass the fainter ones will not be visible; yet even with su=
ch a
glass the scene is a remarkable one. Not only all of the "Seven Sister=
s,"
but many other stars, can be seen twinkling among them. The superiority of
Alcyone to the others, which is not so clear to the naked eye, becomes very
apparent. Alcyone is the large star below the middle of the picture with a
triangle of little stars beside it. To the left or east of Alcyone the two =
most
conspicuous stars are Atlas and Pleione. The latter--which is the uppermost
one--is represented too large in the picture. It requires a sharp eye to see
Pleione without a glass, while Atlas is plainly visible to the unaided visi=
on,
and is always counted among the naked-eye Pleiades, although it does not be=
ar
the name of one of the mythological sisters, but that of their father. The
bright star below and to the right of Alcyone is Merope; the one near the
right-hand edge of the picture, about on a level with Alcyone, is Electra.
Above, or to the north of Electra, are two bright stars lying in a line poi=
nting
toward Alcyone; the upper one of these, or the one farthest from Alcyone, is
Taygeta, and the other is Maia. Above Taygeta and Maia, and forming a little
triangle with them, is a pair of stars which bears the name of Asterope. Ab=
out
half-way between Taygeta and Electra, and directly above the latter, is Cel=
æno.
The naked-eye observer will probably find it
difficult to decide which he can detect the more easily, Celæno or Pleione,
while he will discover that Asterope, although composed of two stars, as se=
en
with a glass, is so faint as to be much more difficult than either Celæno or
Pleione. Unless, as is not improbable, the names have become interchanged in
the course of centuries, the brightness of these stars would seem to have u=
ndergone
remarkable changes. The star of Merope, it will be remembered, was said to =
have
become indistinct, or disappeared, because she married a mortal. At present
Merope is one of those that can be plainly seen with the naked-eye, while t=
he
star of Asterope, who was said to have had the god Mars for her spouse, has
faded away until only a glass can show it. It would appear, then, that
notwithstanding an occasional temporary eclipse, it is, in the long run, be=
tter
to marry a plain mortal than a god. Electra, too, who hid her eyes at the s=
ight
of burning Troy, seems to have recovered from her fright, and is at present,
next to Alcyone, the brightest star in the cluster. But, however we may reg=
ard
those changes in the brightness of the Pleiades which are based upon tradit=
ion,
there is no doubt that well-attested changes have taken place in the
comparative brilliancy of stars in this cluster since astronomy became an e=
xact
science.
Observations of the proper motions of the Plei=
ades
have shown that there is an actual physical connection between them; that t=
hey
are, literally speaking, a flight of suns. Their common motion is toward the
southwest, under the impulse of forces that remain as yet beyond the grasp =
of
human knowledge. Alcyone was selected by Mädler as the central sun around w=
hich
the whole starry system revolved, but later investigations have shown that =
his
speculation was not well founded, and that, so far as we can determine, the
proper motions of the stars are not such as to indicate the existence of any
common center. They appear to be flying with different velocities in every
direction, although--as in the case of the Pleiades--we often find groups of
them associated together in a common direction of flight.
Still another curious fact about the Pleiades =
is
the existence of some rather mysterious nebulous masses in the cluster. In =
1859
Temple discovered an extensive nebula, of a broad oval form, with the star =
Merope
immersed in one end of it. Subsequent observations showed that this strange
phenomenon was variable. Sometimes it could not be seen; at other times it =
was
very plain and large. In Jeaurat's chart of the Pleiades, made in 1779, a v=
ast
nebulous mass is represented near the stars Atlas and Pleione. This has sin=
ce
been identified by Goldschmidt as part of a huge, ill-defined nebula, which=
he
thought he could perceive enveloping the whole group of the Pleiades. Many
observers, however, could never see these nebulous masses, and were incline=
d to
doubt their actual existence. Within the past few years astronomical photog=
raphy,
having made astonishing progress, has thrown new light upon this mysterious
subject. The sensitized plate of the camera, when applied at the focus of a
properly constructed telescope, has proved more effective than the human
retina, and has, so to speak, enabled us to see beyond the reach of vision =
by
means of the pictures it makes of objects which escape the eye. In November,
1885, Paul and Prosper Henry turned their great photographing telescope upon
the Pleiades, and with it discovered a nebula apparently attached to the st=
ar
Maia. The most powerful telescopes in the world had never revealed this to =
the
eye. Yet of its actual existence there can be no question. Their photograph
also showed the Merope nebula, although much smaller, and of a different fo=
rm from
that represented by its discoverer and others. There evidently yet remains =
much
to be discovered in this singular group, and the mingling of nebulous matter
with its stars makes Tennyson's picturesque description of the Pleiades app=
ear
all the more life-like:
&quo=
t;Many
a night I saw the Pleiads, rising through the mellow shade, Glitter like a swarm of fire-flies tang=
led in
a silver braid."
The reader should not expect to be able to see=
the
nebulæ in the Pleiades with an opera-glass. I have thought it proper to men=
tion
these singular objects only in order that he might be in possession of the =
principal
and most curious facts about those interesting stars.[C]
[Footnote C: The Henry Brothers have continued=
the
photographic work described above, and their later achievements are even mo=
re
interesting and wonderful. They have found that there are many nebulous mas=
ses involved
in the group of the Pleiades, and have photographed them. One of the most
amazing phenomena in their great photograph of the Pleiades is a long wisp =
or
streak of nebulous matter, along which eight or nine stars are strung in a
manner which irresistibly suggests an intimate connection between the stars=
and
the nebula. This recalls the recent (August, 1888) discovery made by Prof.
Holden, with the great Lick telescope, concerning the structure of the
celebrated ring nebula in Lyra, which, it appears, is composed of concentric
ovals of stars and nebulous stuff, so arranged that we must believe they are
intimately associated in a most wonderful community.]
Orion will next command our attention. You will
find the constellation in Map No. 19:
"Eastward beyond the region of the Bull Stands great Orion; whoso kens not him =
in
cloudless night Gleaming aloft, s=
hall
cast his eyes in vain To find a
brighter sign in all the heaven."
To the naked eye, to the opera-glass, and to t=
he
telescope, Orion is alike a mine of wonders. This great constellation embra=
ces
almost every variety of interesting phenomena that the heavens contain. Her=
e we
have the grandest of the nebulæ, some of the largest and most beautifully c=
olored
stars, star-streams, star-clusters, nebulous stars, variable stars. I have
already mentioned the positions of the principal stars in the imaginary fig=
ure
of the great hunter. I may add that his upraised arm and club are represent=
ed
by the stars seen in the map above Alpha ([alpha]) or Betelgeuse, one of wh=
ich
is marked Nu ([nu]), and another, in the knob of the club, Chi ([chi]). I h=
ave
also, in speaking of Aldebaran, described the contrast in the colors of
Betelgeuse and Beta ([beta]) or Rigel. Betelgeuse, it may be remarked, is
slightly variable. Sometimes it appears brighter than Rigel, and sometimes =
less
brilliant. It is interesting to note that, according to Secchi's division of
the stars into types, based upon their spectra, Betelgeuse falls into the t=
hird
order, which seems to represent a type of suns in which the process of cool=
ing,
and the formation of an absorptive envelope or shell, have gone on so far t=
hat
we may regard them as approaching the point of extinction. Rigel, on the ot=
her
hand, belongs to the first order or type which represents suns that are
probably both hotter and younger in the order of development. So, then, we =
may
look upon the two chief stars of this great constellation as representing t=
wo
stages of cosmical existence. Betelgeuse shows us a sun that has almost run=
its
course, that has passed into its decline, and that already begins to faint =
and
flicker and grow dim before the on-coming and inevitable fate of extinction;
but in Rigel we see a sun blazing with the fires of youth, splendid in the
first glow of its solar energies, and holding the promise of the future yet
before it. Rigel belongs to a new generation of the universe; Betelgeuse to=
the
universe that is passing. We may pursue this comparison one step farther ba=
ck
and see in the great nebula, which glows dimly in the middle of the
constellation, between Rigel triumphant and Betelgeuse languishing, a still
earlier cosmical condition--the germ of suns whose infant rays may illumina=
te
space when Rigel itself is growing dim.
Turn your glass upon the three stars forming t=
he
Belt. You will not be likely to undertake to count all the twinkling lights
that you will see, especially as many of them appear and disappear as you t=
urn
your attention to different parts of the field. Sweep all around the Belt a=
nd also
between the Belt and Gamma ([gamma]) or Bellatrix. According to the old
astrologers, women born under the influence of the star Bellatrix were luck=
y,
and provided with good tongues. Of course, this was fortunate for their
husbands too!
Below the Belt will be seen a short row of sta=
rs
hanging downward and representing the sword. In the middle of this row is t=
he
great Orion nebula. The star Theta ([theta]) involved in the nebula is
multiple, and the position of this little cluster of suns is such that, as =
has
been said, they seem to be feeding upon the substance of the nebula surroun=
ding
them. Other stars are seen scattered in different parts of the nebula. This
phenomenon can be plainly seen with an opera-glass. Our picture of the Swor=
d of
Orion shows its appearance with a good field-glass. With such a glass sever=
al
fine test-objects will be found in the Sword. One of the best of these is
formed by the two five-pointed stars seen in the picture close together abo=
ve
the nebula. No difficulty will be encountered in separating these stars wit=
h a
field-glass, but it will require a little sharp watching to detect the small
star between the two and just above the line joining them. So, the bending =
row
of faint stars above and to the right of the group just described will be f=
ound
rather elusive as individuals, though easily glimpsed as a whole. Of the gr=
eat
nebula itself not much detail can be seen. Yet by averting the eyes the
extension of the nebulous light in every direction from the center can be
detected and traced, under favorable circumstances, to a considerable dista=
nce.
The changes that this nebula certainly has undergone in the brilliancy, if =
not
in the form, of different parts of it, are perhaps indications of the opera=
tion
of forces, which we know must prevail there, and whose tendency can only be=
in
the direction of condensation, and the ultimate formation of future suns and
worlds. Yet, as the appearance of the nebula in great telescopes shows, we =
can
not expect that the processes of creation will here produce a homologue of =
our
solar system. The curdled appearance of the nebula indicates the formation =
of
various centers of condensation, the final result of which will doubtless b=
e a
group of stars like some of those which we see in the heavens, and whose co=
mmon
motion shows that they are bound together in the chains of reciprocal
gravitation. The Pleiades are an example of such a group.
Do not fail to look for a little star just wes=
t of
Rigel, which, with a good opera-glass, appears to be almost hidden in the
flashing rays of its brilliant companion. If you have also a field-glass, a=
fter
you have detected this shy little twinkler with your opera-glass, try the
larger glass upon it. You will find then that the little star originally se=
en is
not the only one there. A still smaller star, which had before been complet=
ely
hidden, will now be perceived. I may add that, with telescopes, Rigel is on=
e of
the most beautiful double stars in the sky, having a little blue companion
close under its wing. Run your glass along the line of little stars forming=
the
lion's skin or shield that Orion opposes to the onset of Taurus. Here you w=
ill
find some interesting combinations, and the star marked on the map [pi]^6 w=
ill especially
attract your eye, because it is accompanied, about fifteen minutes to the
northwest, by a seventh-magnitude star of a rich orange hue.
Look next at the little group of three stars
forming the head of Orion. Although there is no nebula here, yet these star=
s,
as seen with the naked eye, have a remarkably nebulous look, and Ptolemy
regarded the group as a nebulous star. The largest star is called Lambda
([lambda]); the others are Phi ([phi]) one and two. An opera-glass will show
another star above ([lambda]), and a fifth star below [phi]^2 which is the =
farthest
of the two Phis from Lambda. It will also reveal a faint twinkling between
[lambda] and [phi]^1. A field-glass shows that this twinkling is produced b=
y a
pretty little row of three stars of the eighth and ninth magnitudes.
In fact, Orion is such a striking object in the
sky that more than one attempt has been made to steal away its name and
substitute that of some modern hero. The University of Leipsic, in 1807,
formally resolved that the stars forming the Belt and Sword of Orion should
henceforth be known as the constellation of Napoleon. As if to offset this,=
an
Englishman proposed to rename Orion for the British naval bull-dog Nelson. =
But "Orion
armed" has successfully maintained his name and place against all come=
rs.
As becomes the splendor of his constellation, Orion is a tremendous hero of
antiquity, although it must be confessed that his history is somewhat shado=
wy
and uncertain, even for a mythological story. All accounts agree, however, =
that
he was the mightiest hunter ever known, and the Hebrews claimed that he was=
no
less a person than Nimrod himself.
The little constellations of Lepus and Columba,
below Orion, need not detain us long. You will find in them some pretty
combinations of stars. In Lepus is the celebrated "Crimson Star,"
which has been described as resembling a drop of blood in color--a truly
marvelous hue for a sun--but, as it is never brighter than the sixth magnit=
ude,
and from that varies down to the ninth, we could hardly hope to see its col=
or well
with an opera-glass. Besides, the observer would have difficulty in finding=
it.
We will now turn to the constellation of Canis
Major, represented in Map No. 20. Although, as a constellation, it is not t=
o be
compared with the brilliant Orion, yet, on account of the unrivaled
magnificence of its chief star, Canis Major presents almost as attractive a
scene as its more extensive rival. Everybody has heard of Sirius, or the
Dog-Star, and everybody must have seen it flashing and scintillating so
splendidly in the winter heavens, that to call it a first-magnitude star do=
es
it injustice, since no other star of that magnitude is at all comparable wi=
th
it. Sirius, in fact, stands in a class by itself as the brightest star in t=
he
sky. Its light is white, with a shade of green, which requires close watchi=
ng
to be detected. When it is near the horizon, or when the atmosphere is very
unsteady, Sirius flashes prismatic colors like a great diamond. The question
has been much discussed, as to whether Sirius was formerly a red star. It is
described as red by several ancient authors, but it seems to be pretty well
established that these descriptions are most of them due to a blunder made =
by
Cicero in his translation of the astronomical poem of Aratus. It is not imp=
ossible,
though it is highly improbable, that Sirius has changed color.
So intimately was Sirius connected in the mind=
s of
the ancient Egyptians with the annual rising of the Nile, that it was called
the Nile-star. When it appeared in the morning sky, just before sunrise, the
season of the overflowing of the great river was about to begin, and so the=
appearance
of this star was regarded as foretelling the coming of the floods. The dog-=
days
got their name from Sirius, as they occur at the time when that star rises =
with
the sun.
Your eyes will be fairly dazzled when you turn
your glass upon this splendid star. By close attention you will be able to
perceive a number of faint stars, mere points by comparison, in the immedia=
te
neighborhood of Sirius. There are many interesting objects in the
constellation. The star marked Nu ([nu]) in the map is really triple, as the
smallest glass will show. Look next at the star-group 41 M. The cloud of mi=
nute
stars of which it is composed can be very well seen with a field-glass or a=
powerful
opera-glass. The star 22 is of a very ruddy color that contrasts beautifully
with the light of Epsilon ([epsilon]), which can be seen in the same field =
of
view with an opera-glass. Between the stars Delta ([delta]) and [omicron]¹ =
and
[omicron]² there is a remarkable array of minute stars, as shown in the
accompanying cut. One never sees stars arranged in streams or rows, like th=
ese,
without an irresistible impression that the arrangement can not be accident=
al;
that some law must have been in operation which associated them together in=
the
forms which we see. Yet, when we reflect that these are all suns, how far d=
o we
seem to be from understanding the meaning of the universe!
The extraordinary size and brilliancy of Sirius
might naturally enough lead one to suppose that it is the nearest of the st=
ars,
and such it was once believed to be. Observations of stellar parallax, howe=
ver,
show that this was a mistake. The distance of Sirius is so great that no sa=
tisfactory
determination of it has yet been made. We may safely say, though, that that
distance is, at the least calculation, 50,000,000,000,000 miles. In other
words, Sirius is about 537,000 times as far from the earth as the sun is. T=
hen,
since light diminishes as the square of the distance increases, the sun, if
placed as far from us as Sirius is, would send us, in round numbers, 288,00=
0,000,000
times less light than we now receive from it. But Sirius actually sends us =
only
about 4,000,000,000 times less light than the sun does; consequently Sirius
must shine 288,000,000,000/4,000,000,000 =3D 72 times as brilliantly as the=
sun.
If we adopt Wollaston's estimate of the light of Sirius, as compared with t=
hat
of the sun, viz., 1/20,000,000,000, we shall still find that the actual
brilliancy of that grand star is more than fourteen times as great as that =
of
our sun. But as observations on the companion of Sirius show that Sirius's =
mass
is fully twenty times the sun's, and since the character of Sirius's spectr=
um
indicates that its intrinsic brightness, surface for surface, is much super=
ior
to the sun's, it is probable that our estimate of the star's actual brillia=
ncy,
as compared with what the sun would possess at the same distance, viz.,
seventy-two times, is much nearer the truth. It is evident that life would =
be
insupportable upon the earth if it were placed as near to Sirius as it is t=
o the
sun. If the earth were a planet belonging to the system of Sirius, in order=
to
enjoy the same amount of heat and light it now receives, it would have to be
removed to a distance of nearly 800,000,000 miles, or eight and a half times
its distance from the sun. Its time of revolution around Sirius would then =
be
nearly five and a half years, or, in other words, the year would be lengthe=
ned
five and a half times.
But, as I have said, the estimate of Sirius's
distance used in these calculations is the smallest that can be accepted. G=
ood
authorities regard the distance as being not less than 100,000,000,000,000
miles; in which case the star's brilliancy must be as much as 228 times gre=
ater
than that of the sun! And yet even Sirius is probably not the greatest sun
belonging to the visible universe. There can be little doubt that Canopus, =
in
the southern hemisphere, is a grander sun than Sirius. To our eyes, Canopus=
is
only about half as bright as Sirius, and it ranks as the second star in the
heavens in the order of brightness. But while Sirius's distance is measurab=
le,
that of Canopus is so unthinkably immense that astronomers can get no grip =
upon
it. If it were only twice as remote as Sirius, it would be equal to two of =
the
latter, but in all probability its distance is much greater than that. And
possibly even Canopus is not the greatest gem in the coronet of creation.
Sirius, as we saw when talking of Procyon (see
Chapter I), is a double star. For many years after Bessel had declared his
belief that the Dog-Star was subjected to the attraction of an invisible
companion, telescopes failed to reveal the accompanying star.[D] Finally, in
1862, a new telescope that Alvan Clark had just finished and was testing, b=
rought
the hidden star into view. The suggestion that it may shine by reflected li=
ght
from Sirius has been made. In that case it must, of course, be a planet, bu=
t a
planet of such stupendous magnitude that the imagination can scarcely grasp=
it;
a planet probably as large as our sun, perhaps larger; a planet equal in si=
ze
to more than a million earths! But, as was remarked of the faint stars in A=
lpha
Capricornis, it is probable that the hypothesis of reflected light is not t=
he
true one. More probably the companion of Sirius shines with light of its ow=
n, though
its excessive faintness in comparison with its bulk indicates that its
condition must be very different from that of an ordinary star.
[D=
] The
following extract from a letter by Bessel to Humboldt, written in 1844 (see
"Cosmos," vol. iii, p. 186), is interesting, in view of the disco=
veries
made since then: "At a=
ll
events I continue in the belief that Procyon and Sirius are true double stars,
consisting of a visible and an
invisible star. No reason exists for considering luminosity an essential property =
of
these bodies. The fact that
numberless stars are visible is evidently no proof against the existence of an
equally incalculable number=
of
invisible ones. The physical difficulty of a change in the proper motion is
satisfactorily set aside by=
the
hypothesis of dark stars."
Readers of Voltaire will remember that the her=
o of
his extraordinary story of "Micromegas" came from an imaginary pl=
anet
circling around Sirius. Inasmuch as Voltaire, together with Dean Swift,
ascribed two moons to Mars many years before they were discovered (probably
suggested by a curiously mistaken interpretation by Kepler of an anagram in
which Galileo had concealed his discovery of the ring of Saturn), it is all=
the
more interesting that the great infidel should have imagined an enormous pl=
anet
circling around the Dog-Star. But Voltaire went far astray when he ascribed=
a
gigantic stature to his "Sirian." He makes Micromegas, whose world
was 21,600,000 times larger in circumference than the earth, more than twen=
ty
miles tall, so that when he visited our little planet he was able to wade
through the oceans and step over the mountains without inconvenience, and, =
when
he had scooped up some of the inhabitants on his thumb-nail, was obliged to=
use
a powerful microscope in order to see them. Voltaire should rather have gon=
e to
some of the most minute of the asteroids for his giant, for under the
tremendous gravitation of such a world as he has described Micromegas himse=
lf
would have been a fit subject for microscopic examination. But, however muc=
h we
may doubt the stature of Voltaire's visitor from Sirius, we can not doubt t=
he
soundness of the conclusion at which he arrived, after having, by an ingeni=
ous
arrangement, succeeded in holding a conversation with some earthly philosop=
hers
under his microscope, namely, that these infinitely little creatures posses=
sed
a pride that was almost infinitely great.
East and south of Canis Major, which, by-the-w=
ay,
is said to represent one of Orion's hounds, is part of the constellation Ar=
go,
which stands for the ship in which Jason sailed in search of the golden fle=
ece.
The observer will find many objects of interest here, although some of them=
are
so close to the horizon in our latitudes that much of their brilliancy is l=
ost.
Note the two stars [zeta] and [pi] near the lower edge of the map, then swe=
ep
slowly over the space lying between them. About half-way your attention wil=
l be
arrested by a remarkable stellar arrangement, in which a beautiful half-cir=
cle
of small stars curving above a larger star, which is reddish in color, is
conspicuous. This neighborhood will be found rich in stars that the naked e=
ye
can not see. Just below the star [eta], in Canis Major, is another fine gro=
up.
The star [pi], which is deep yellow or orange, has three little stars above=
it,
two of which form a pretty pair. The star [xi] has a companion, which forms=
a
fine test for an opera-glass, and is well worth looking for. Look also at t=
he
cluster 93 M, just above and to the west of [xi]. The stars [mu] and [kappa]
are seen double with an opera-glass.
The two neighboring clusters, 46 M and 38^8, a=
re
very interesting objects. To see them well, use a powerful field-glass. A
"fiery fifth-magnitude star," as Webb calls it, can be seen in the
field at the same time. The presence of the Milky-Way is manifest by the
sprinkling of stars all about this region. In fact, the attentive observer =
will
before this have noticed that the majority of the most brilliant constellat=
ions
lie either in the Milky-Way or along its borders. Cassiopeia, as we saw, si=
ts
athwart the galaxy whose silvery current winds in and out among the stars of
her "chair"; Perseus is aglow with its sheen as it wraps him about
like a mantle of stars; Taurus has the tips of his horns dipped in the great
stream; it flows between the shining feet of Gemini and the head and should=
ers
of Orion as between starry banks; the peerless Sirius hangs like a gem pend=
ent
from the celestial girdle. In the southern hemisphere we should find the be=
autiful
constellation of the ship Argo, containing Canopus, sailing along the
Milky-Way, blown by the breath of old romance on an endless voyage; the
Southern Cross glitters in the very center of the galaxy; and the bright st=
ars
of the Centaur might be likened to the heads of golden nails pinning this
wondrous scarf, woven of the beams of millions of tiny stars, against the d=
ome
of the sky. Passing back into the northern hemisphere we find Scorpio,
Sagittarius, Aquila, the Dolphin, Cygnus, and resplendent Lyra, all strung
along the course of the Milky-Way.
Turning now to the constellation Monoceros, we
shall find a few objects worthy of attention. This constellation is of
comparatively modern origin, having been formed by Bartschius, whose chief
title to distinction is that he married the daughter of John Kepler. The re=
gion
around the stars 8, 13, and 17 will be found particularly rich, and the clu=
ster
2^7 shows well with a strong glass. Look also at the cluster 50 M, and comp=
are
its appearance with that of the clusters in Argo.
With these constellations we finish our review=
of
the stellar wonders that lie within the reach of so humble an instrument as=
an
opera-or field-glass. We have made the circuit of the sky, and the hosts th=
at illumine
the vernal heavens are now seen advancing from the east, and pressing close
upon the brighter squadrons of winter. Their familiar figures resemble the
faces of old friends whom we are glad to welcome. These starry acquaintance=
s never
grow wearisome. Their interest for us is as fathomless as the deeps of spac=
e in
which they shine. The man never yet lived whose mind could comprehend the f=
ull
meaning of the wondrous messages that they flash to us upon the wings of li=
ght.
As we watch them in their courses, the true music of the spheres comes to o=
ur listening
ears, the chorus of creation--faint with distance, for it is by slow approa=
ches
that man draws near to it--chanting the grandest of epics, the Poem of the
Universe; and the theme that runs through it all is the reign of law. Do no=
t be
afraid to become a star-gazer. The human mind can find no higher exercise. =
He
who studies the stars will discover--
&quo=
t;An
endless fountain of immortal drink Pouring unto us from heaven's brink.&qu=
ot;
<=
span
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Calibri'>CHAPTER V - THE MOON, THE PLANETS, AND THE SUN.<=
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"= ;It is a most beautiful and delightful sight," exclaims Galileo, in describing the discoveries he had made with his telescope, "to behold the body of= the moon, which is distant from us nearly sixty semi-diameters of the earth, as near as if it was at a distance of only two of the same measures.... And, consequently, any one may know with the certainty that is due to the use of= our senses that the moon assuredly does not possess a smooth and polished surfa= ce, but one rough and uneven, and, just like the face of the earth itself, is everywhere full of vast protuberances, deep chasms, and sinuosities."<= o:p>
There was, perhaps, nothing in the long series=
of
discoveries with which Galileo astonished the world after he had constructed
his telescope, which, as he expresses it, "was devised by me through G=
od's
grace first enlightening my mind," that had a greater charm for him th=
an
his lunar observations. Certainly there was nothing which he has described =
with
greater enthusiasm and eloquence. And this could hardly have been otherwise,
for the moon was the first celestial object to which Galileo turned his
telescope, and then for the first time human eyes may be said to have actua=
lly
looked into another world than the earth, though his discoveries and those =
of
his successors have not realized all the poetic fancies about the moon
contained in the verses that are ascribed to Orpheus:
&quo=
t;And
he another wandering world has made Which gods Selene name, and men the moo=
n. It mountains, cities has, and temples
grand."
Yet Galileo's observations at once upset the
theory, for which Apollonius was responsible, and which seems to have been
widely prevalent up to his time, that the moon was a smooth body, polished =
like
a mirror, and presenting in its light and dark spots reflections of the con=
tinents
and oceans of the earth. He also demonstrated that its surface was covered =
with
plains and mountains, but the "cities and temples" of the moon ha=
ve
remained to our time only within the ken of romance.
Galileo's telescope, as I have before remarked,
was, in the principle of its construction, simply an opera-glass of one tub=
e.
He succeeded in making a glass of this kind that magnified thirty diameters=
, a
very much higher power than is given to the opera-and field-glasses of to-d=
ay.
Yet he had to contend with the disadvantages of single lenses, achromatic c=
ombinations
of glass for optical purposes not being contrived until nearly a hundred ye=
ars
after his death, and so his telescope did not possess quite as decided a
superiority over a modern field-glass as the difference in magnifying power
would imply. In fact, if the reader will view the moon with a first-rate
field-glass, he will perceive that the true nature of the surface of the lu=
nar
globe can be readily discerned with such an instrument. Even a small
opera-glass will reveal much to the attentive observer of the moon; but for
these observations the reader should, if possible, make use of a field-glas=
s,
and the higher its power the better. The illustrations accompanying this
chapter were made by the author with the aid of a glass magnifying seven
diameters.
Of course, the first thing the observer will w=
ish
to see will be the mountains of the moon, for everybody has heard of them, =
and
the most sluggish imagination is stirred by the thought that one can look o=
ff into
the sky and behold "the eternal hills" of another planet as solid=
and
substantial as our own. But the chances are that, if left to their own
guidance, ninety-nine persons out of a hundred would choose exactly the wro=
ng
time to see these mountains. At any rate, that is my experience with people=
who
have come to look at the moon through my telescope. Unless warned beforehan=
d,
they invariably wait until full moon, when the flood of sunshine poured
perpendicularly upon the face of our satellite conceals its rugged features=
as
effectually as if a veil had been drawn over them. Begin your observations =
with
the appearance of the narrowest crescent of the new moon, and follow it as =
it
gradually fills, and then you will see how beautifully the advancing line of
lunar sunrise reveals the mountains, over whose slopes and peaks it is clim=
bing,
by its ragged and sinuous outline. The observer must keep in mind the fact =
that
he is looking straight down upon the tops of the lunar mountains. It is lik=
e a
view from a balloon, only at a vastly greater height than any balloon has e=
ver
attained. Even with a powerful telescope the observer sees the moon at an
apparent distance of several hundred miles, while with a field-glass,
magnifying seven diameters, the moon appears as if thirty-five thousand mil=
es
off. The apparent distance with Galileo's telescope was eight thousand mile=
s.
Recollect how when seen from a great height the rugosities of the earth's s=
urface
flatten out and disappear, and then try to imagine how the highest mountain=
s on
the earth would look if you were suspended thirty-five thousand miles above
them, and you will, perhaps, rather wonder at the fact that the moon's
mountains can be seen at all.
It is the contrast of lights and shadows that =
not
only reveals them to us, but enables us to measure their height. On the moon
shadows are very much darker than upon the earth, because of the extreme ra=
rity
of the moon's atmosphere, if indeed it has any atmosphere at all. By steppi=
ng around
the corner of a rock there, one might pass abruptly from dazzling noonday i=
nto
the blackness of midnight. The surface of the moon is extraordinarily rough=
and
uneven. It possesses broad plains, which are probably the bottoms of ancient
seas that have now dried up, but these cover only about two fifths of the
surface visible to us, and most of the remaining three fifths are exceeding=
ly
rugged and mountainous. Many of the mountains of the moon are, foot for foo=
t, as
lofty as the highest mountains on the earth, while all of them, in proporti=
on
to the size of the moon's globe, are much larger than the earth's mountains=
. It
is obvious, then, that the sunshine, as it creeps over these Alpine landsca=
pes
in the moon, casting the black shadows of the peaks and craters many miles
across the plains, and capping the summits of lofty mountains with light, w=
hile
the lower regions far around them are yet buried in night, must clearly rev=
eal
the character of the lunar surface. Mountains that can not be seen at all w=
hen
the light falls perpendicularly upon them, or, at the most, appear then mer=
ely
as shining points, picture themselves by their shadows in startling silhoue=
ttes
when illuminated laterally by the rising sun.
But at full moon, while the mountains hide
themselves in light, the old sea-beds are seen spread out among the shining
table-lands with great distinctness. Even the naked eye readily detects the=
se
as ill-defined, dark patches upon the face of the moon, and to their presen=
ce
are due the popular notions that have prevailed in all quarters of the worl=
d about
the "Man in the Moon," the "Woman in the Moon," "J=
acob
in the Moon," the "Hare in the Moon," the "Toad in the
Moon," and so on. But, however clearly one may imagine that he discern=
s a
man in the moon while recalling the nursery-rhymes about him, an opera-glass
instantly puts the specter to flight, and shows the round lunar disk
diversified and shaded like a map.[E]
[E=
] I
should, perhaps, qualify the statement in the text slightly in favor of a lunar lady=
to
whom Mr. Henry M. Parkhurst=
first
called my attention. About nine days after new moon a rather pretty and
decidedly feminine face app=
ears
on the western half of the disk. It is formed by the mountains and table=
-lands
embraced by the Sea of Sere=
nity,
the Sea of Tranquillity, the Sea
of Vapors, etc., and is best seen with the aid of an opera-glass of low power. T=
he
face is readily distinguish=
able
on Rutherfurd's celebrated photograph of the full moon. It is necessary=
for
this purpose to turn the
photograph upside down, since it is a telescopic picture, and consequen=
tly
reversed. The crater Tycho =
forms
a breastpin for the lady, and Menelaus glitters like a diamond
ornament in her hair, while=
the
range of the Apennines resembles a sort of coronet resting on her forehead. =
This
same woman in the moon, it
appears, was described by Dr. James Thompson years ago, and, for augh=
t I
know, she may be the Diana =
to
whom Herrick sang:
"Queen and huntress chaste and fair, Seated in thy silver chair, <=
span
style=3D'mso-spacerun:yes'> Now the Sun is laid to sleep,=
State in wonted manner keep. =
Hesperus entreats thy light, =
Goddess excellently bright.&q=
uot;
A feature of the full moon's surface that
instantly attracts attention is the remarkable brightness of the southern p=
art
of the disk, and the brilliant streaks radiating from a bright point near t=
he
lower edge. The same simile almost invariably comes to the lips of every pe=
rson
who sees this phenomenon for the first time--"It looks like a peeled
orange." The bright point, which is the great crater-mountain Tycho, l=
ooks
exactly like the pip of the orange, and the light-streaks radiating from it=
in all
directions bear an equally striking resemblance to the streaks that one sees
upon an orange after the outer rind has been removed. I shall have somethin=
g more
to say about these curious streaks further on; in the mean time, let us gla=
nce
at our little sketch-map of the moon.
The so-called seas are marked on the map, for =
the
purpose of reference, by the letters which they ordinarily bear in lunar ma=
ps.
The numerals indicate craters, or ring-plains, and mountain-ranges. The
following key-list will enable the reader to identify all the objects that =
are lettered
or numbered upon the map. I have given English translations of the Latin na=
mes
which the old astronomers bestowed upon the seas:
Seas, Gulfs, and Marshes.
A. T=
he
Crisian Sea. B. Humboldt Sea.
Mountains and Crater Rings.
1.
Grimaldi. 2. Letronne. 3. Gassendi. 4. Euclides. 5. Bullialdus. 6. Pitatus. 7. Schickhard. 8. Longomontanus. 9. Tycho. 10. Maginus. 11. Clavius. 12. Newton. 13. Maurolycus. 14. Stöfler. 15. Walter. 16. Regiomontanus. 17. Purbach. 18. Arzachel. 19. Alphonsus. 20. Ptolemaus. 21. Hipparchus. 22. Albategnius. 23. Theophilus. 24. Cyrillus. 25. Catharina. 26. The Altai Mts. 27. Piccolomini. 28. Petavius. 29. Langrenus. 80. Proclus. 31. Cleomedes. 32. Atlas. 33. Hercules. 34. Posidonius. 35. Plinius. 36. Menelaus. 37. Manilius. 38. The Caucasus Mts. 39. Eudoxus. 40. Aristotle. 41. The Alps. 42. Plato. 43. Archimedes. 44. The Apennines. 45. Eratosthenes. 46. Copernicus. 47. The Carpathian Mts. 48. Timocharis. 49. Lambert. 50. Euler. 51. Aristarchus. 52. Kepler. 53. Flamsteed.
The early selenographers certainly must have b=
een
men of vivid imagination, and the romantic names they gave to the lunar
landscapes, and particularly to the "seas," add a charm of their =
own
to the study of the moon. Who would not wish to see the "Bay of
Rainbows," or the "Lake of Dreams," or the "Sea of
Tranquillity," if for no other reason than a curiosity to know what co=
uld
have induced men to give to these regions in the moon such captivating titl=
es?
Or who would not desire to visit them if he could? though no doubt we should
find them, like the "Delectable Mountains" in the "Pilgrim's
Progress," most charming when seen from afar.
The limited scale of our map, of course, rende=
rs
it impossible to represent upon it more than a comparatively small number of
the lunar mountains that have received names. In selecting those to be put =
in
the map I have endeavored to choose such as, on account of their size, thei=
r situation,
or some striking peculiarity, would be most likely to attract the attention=
of
a novice. The observer must not expect to see them all at once, however. The
lunar features change their appearance to a surprising extent, in accordance
with the direction of their illumination. Some great mountain-masses and
ring-plains, or craters, which present scenes of magnificence when the sun =
is
rising or setting upon them, disappear under a perpendicular light, such as
they receive at full moon. The great crater-plain, known as Maginus, number=
ed
10 in our map, is one of these. The broken mountain-wall surrounding this v=
ast depressed
plain rises in some places to a height of over fourteen thousand feet above=
the
valley within, and the spectacle of sunrise upon Maginus, seen with a power=
ful
telescope, is a most impressive sight, and even with a field-glass is very
interesting. Yet, a few days later, Maginus vanishes, as if it had been
swallowed up, and as Beer and Mädler have expressed it, "the full moon
knows no Maginus." The still grander formation of mountain, plain, and
crater, called Clavius (11 in the map), disappears almost as completely as
Maginus at full moon, yet, under the proper illumination, it presents a
splendid pageant of light and shadow.
On the other hand, some of the lunar mountains
shine vividly at full moon, and can be well seen then, though, of course, o=
nly
as light spots, since at that time they cast no shadows. Menelaus (36 in the
map), Aristarchus (51), Proclus (30), Copernicus (46), and Kepler (52), are=
among
these shining mountains. Aristarchus is the most celebrated of them all, be=
ing
the brightest point on the moon. It can even be seen glimmering on the dark
side of the moon--that is to say, when no light reaches it except that whic=
h is
reflected from the earth. With a large telescope, Aristarchus is so dazzlin=
gly
bright under a high sun, that the eye is partly blinded in gazing at it. It
consists of a mountain-ring surrounding a circular valley, about twenty-eig=
ht
miles in diameter. The flanks of these mountains, especially on their inner=
slopes,
and the floor of the valley within, are very bright, while a peak in the ce=
nter
of the valley, about as high as Storm-King Mountain on the Hudson, shines w=
ith
piercing brilliancy. Sir William Herschel mistook it for a volcano in actio=
n.
It certainly is not an active volcano, but just what makes it so dazzling n=
o one
knows. The material of which this mountain is formed would seem to possess a
higher reflective power than that of any other portion of the moon's surfac=
e. One
is irresistibly reminded of the crystallized mountains described in the
celebrated "Moon Hoax" of Richard Adams Locke. With an opera-glas=
s you
can readily recognize Aristarchus as a bright point at full moon. With a
field-glass it is better seen, and some of the short, light rays surroundin=
g it
are perceived, while, when the sun is rising upon it, about four days after
first quarter, its crateriform shape can be detected with such a glass.
The visibility of Aristarchus on the dark side=
of
the moon leads us to a brief consideration of the illumination by the earth=
of
that portion of the moon's surface which is not touched directly by sunligh=
t at
new and old moon. This phenomenon is shown in the accompanying illustration.
Not only can the outlines of the dark part of the moon be seen under such c=
ircumstances,
but even the distinction in color between the dusky "seas" and the
more brilliant table-lands and mountain-regions can be perceived, and with
powerful telescopes many minor features come into sight. A little considera=
tion
must convince any one, as it convinced Galileo more than two hundred and se=
venty-five
years ago, that the light reflected from the earth upon the moon is suffici=
ent
to produce this faint illumination of the lunar landscapes. We have only to
recall the splendors of a night that is lighted by a full moon, and then to=
recollect
that at new or old moon the earth is "full" as seen from our sate=
llite,
and that a full earth must give some fourteen times as much light as a full
moon, in order to realize the brilliancy of an earth-lit night upon the moo=
n.
As the moon waxes to us, the earth wanes to the moon, and vice versa, and so
the phenomenon of earth-shine on the lunar surface must be looked for before
the first quarter and after the last quarter of the moon.
The reader will find it an attractive occupati=
on
to identify, by means of the map, the various "seas,"
"lakes," and "marshes," for not only are they interesti=
ng
on account of the singularity of their names, but they present many remarka=
ble
differences of appearance, which may be perceived with the instrument he is
supposed to be using. The oval form of the Crisian Sea (A), which is the fi=
rst
of the "seas" to come into sight at new moon, makes it a very
striking object. With good telescopes, and under favorable illumination, a
decidedly green tint is perceived in the Crisian Sea. It measures about two
hundred and eighty by three hundred and fifty-five miles in extent, and is,
perhaps, the deepest of all the old sea-beds visible on the moon. It is
surrounded by mountains, which can be readily seen when the sun strikes ath=
wart
them a few days after new or full moon. On the southwestern border a stupen=
dous
mountain-promontory, called Cape Agarum, projects into the Crisian Sea fift=
y or
sixty miles, the highest part rising precipitously eleven thousand feet abo=
ve
the floor of the sea. I have seen Cape Agarum very clearly defined with a
field-glass. Near the eastern border is the crater-mountain Proclus, which I
have already mentioned as possessing great brilliancy under a high sun, bei=
ng
in this respect second only to Aristarchus.
From the foot of Proclus spreads away the some=
what
triangular region called the Marsh of Sleep (F). The term
"golden-brown," which has been applied to it, perhaps describes i=
ts
hue well enough. With a telescope it is a most interesting region, but with
less powerful instruments one must be content with recognizing its outline =
and
color.
The broad, dark-gray expanse of the Sea of
Tranquillity (G) will be readily recognized by the observer, and he will be
interested in the mottled aspect which it presents in certain regions, caus=
ed
by ridges and elevations, which, when this sea-bottom was covered with wate=
r,
may have formed shoals and islands.
The Sea of Fertility (X) is remarkable for its
irregular surface, and the long, crooked bays into which its southern extre=
mity
is divided.
The Sea of Nectar (V) is connected with the Se=
a of
Tranquillity by a broad strait (one would naturally anticipate from their n=
ames
that there must be some connection between them), while between it and the =
Sea
of Fertility runs the range of the Pyrenees Mountains, twelve thousand feet=
high,
flanked by many huge volcanic mountain-rings.
The Sea of Serenity (H), lying northeast of the
Sea of Tranquillity, is about four hundred and twenty miles broad by four
hundred and thirty miles long, being very nearly of the same area as our
Caspian Sea. It is deeper than the Sea of Tranquillity, and a greenish hue =
is
sometimes detected in its central parts. It deepens toward the middle. Thre=
e quarters
of its shore-line are bordered by high mountains, and many isolated elevati=
ons
and peaks are scattered over its surface. In looking at these dried-up seas=
of
the moon, one is forcibly reminded of the undulating and in some places
mountainous character of terrestrial sea-bottoms, as shown by soundings and=
the
existence of small islands in the deep sea, like the Bermudas, the Azores a=
nd
St. Helena. The Sea of Serenity is divided nearly through the center by a
narrow, bright streak, apparently starting from the crater-mountain Menelaus
(36 in the map), but really taking its rise at Tycho far in the south. This
curious streak can be readily detected even with a small opera-glass. Just =
what
it is no one is prepared to say, and so the author of the "Moon Hoax&q=
uot;
was fairly entitled to take advantage of the romancer's license, and declare
that "its edge throughout its whole length of three hundred and forty
miles is an acute angle of solid quartz-crystal, brilliant as a piece of
Derbyshire spar just brought from the mine, and containing scarcely a fract=
ure
or a chasm from end to end!" Along the southern shore, on either side =
of
Menelaus, extends the high range of the Hæmus Mountains. South and southeas=
t of
the Sea of Serenity are the Sea of Vapors (L), the Central Gulf (M), and the
Gulf of Heats (N). The observer will notice at full moon three or four curi=
ous
dark spots in the region occupied by these flat expanses. On the north and
northwest of the Sea of Serenity are the Lake of Death (D), and the Lake of
Dreams (E), chiefly remarkable for their names.
The Sea of Showers (O) is a very interesting
region, not only in itself, but on account of its surroundings. Its level is
very much broken by low, winding ridges, and it is variegated by numerous
light-streaks. At its western end it blends into the Marsh of Mists (I) and=
the
Marsh of Putrefaction (K). On its northeast border is the celebrated Sinus =
Iridum,
or Bay of Rainbows (P), upon which selenographers have exhausted the adject=
ives
of admiration. The bay is semicircular in form, one hundred and thirty-five
miles long and eighty-four miles broad. Its surface is dark and level. At
either end a splendid cape extends into the Sea of Showers, the eastern one
being called Cape Heraclides, and the western Cape Laplace. They are both
crowned by high peaks. Along the whole shore of the bay runs a chain of
gigantic mountains, forming the southern border of a wild and lofty plateau,
called the Sinus Iridum Highlands. Of course, a telescope is required to see
the details of this "most magnificent of all lunar landscapes," a=
nd
yet much can be done with a good field-glass. With such an instrument I have
seen the capes at the ends of the bay projecting boldly into the dark, level
expanse surrounding them, and the high lights of the bordering mountains
sharply contrasted with the dusky semicircle at their feet, and have been a=
ble to
detect the presence of the low ridges that cross the front of the bay like
shoals, separating it from the "sea" outside. Two or three days a=
fter
first quarter, the shadows of the peaks about the Bay of Rainbows may be se=
en.
The Bay of Dew (R) above the Bay of Rainbows, and the Sea of Cold (C), are =
the
northernmost of the dark levels visible. It was in keeping with the supposed
character of this region of the Moon that Riccioli named two portions of it=
the
Land of Hoar Frost and the Land of Drought.
Extending along the eastern side of the disk is
the great Ocean of Storms (Q), while between the Ocean of Storms and the mi=
ddle
of the moon lies the Sea of Clouds (S). Both of these are very irregular in
outline, and much broken by ridges and mountains. The Sea of Humors (T),
although comparatively small, is one of the most easily seen of all the lun=
ar plains.
To the naked eye it looks like a dark, oval patch on the moon. With a teles=
cope
it is seen, under favorable conditions, to possess a decided green tint.
Humboldt Sea (B) and the South Sea (Z) belong principally to that part of t=
he
moon which is always turned away from the earth, and only their edges proje=
ct
into the visible hemisphere, although, under favorable librations, their
farther borders, lined as usual with mountain-peaks, may be detected. For o=
ur
purposes they possess little interest.
Let us now glance at some of the mountains and
"craters." The dark oval called Grimaldi (1) can be detected by t=
he
naked eye, or at least it has been thus seen, although it requires a sharp =
eye;
and perhaps a shade or a pair of eye-glasses of London smoke-glass, to take=
off
the glare of the moon, should be used in looking for it.[F] It is simply a
plain, containing some fourteen thousand square miles, remarkable for its d=
ark color,
and surrounded by mountains. Schickhard (7) is another similar plain, nearl=
y as
large, but not possessing the same dark tint in the interior. The huge
mountains around Schickhard make a fine spectacle when the sun is rising up=
on
them shortly before full moon.
[F]
There are other uses to which such eye-glasses may be put by sky-gazers. I habitually carry=
a
pair for studying clouds. I=
t is
wonderful how much the effect of great cloud-masses is heightened by them, especially wh=
en
seen in a bright light. Del=
icate
curls and striæ of cirrus, which escape the uncovered eye in the glare of sunlight, can=
be
readily detected and studie=
d by
the use of neutral-tinted eye-glasses or spectacles.
Tycho (9) is the most famous of the
crater-mountains, though not the largest. It is about fifty-four miles acro=
ss
and three miles deep. In its center is a peak five or six thousand feet hig=
h.
Tycho is the radial point of the great light-streaks that, as I have already
remarked, cause the southern half of the moon to be likened to a peeled ora=
nge.
It is a tough problem in selenography to account for these streaks. They ar=
e best
seen at full moon. They can not be seen at all until the sun has risen to a
certain elevation above them, 25° according to Neison; but, when they once
become visible, they dominate everything. They turn aside for neither mount=
ains
nor plains, but pass straight on their courses over the ruggedest regions of
the moon, retaining their brilliancy undiminished, and pouring back such a
flood of reflected light that they completely conceal some of the most
stupendous mountain-masses across which they lie. They clearly consist of
different material from that of which the most of the moon's surface is
composed--a material possessing a higher reflective power. In this respect =
they
resemble Aristarchus and other lunar craters that are remarkable for their
brilliancy under a high illumination. Tycho itself, the center or hub, from
which these streaks radiate like spokes, is very brilliant in the full moon.
But immediately around Tycho there is a dark rim some twenty-five miles bro=
ad.
Beyond this rim the surface becomes bright, and the bright region extends a=
bout
ninety miles farther. Out of it spring the great rays or streaks, which vary
from ten to twenty miles in width, and many of which are several hundred mi=
les
long--one, which we have already mentioned as extending across the Sea of
Serenity, being upward of two thousand miles in length. It has been truly s=
aid
that we have nothing like these streaks upon the earth, and so there is no
analogy to go by in trying to determine their nature. It has been suggested
that if the moon had been split or shattered from within by some tremendous
force, and molten matter from the interior had been thrust up into the crac=
ks
thus formed, and had cooled there into broad seams of rock, possessing a hi=
gher
reflective power than the surrounding surface of the moon, then the appeara=
nces
presented would not be unlike what we actually see. But there are serious
objections to such a view, which we have not space to discuss here. It is
enough to say that the nature of these streaks is still a question awaiting
solution, and here is an opportunity for an important discovery, but not on=
e to
be achieved with an opera-glass.
I may add an interesting suggestion as to the
nature of these streaks made by the Rev. Mr. Grensted. He holds that the air
and water of the moon were chemically, and not mechanically, absorbed in the
process of oxidation which went on at the time when her surface temperature=
was
above a red heat. Having a much larger surface in proportion to her bulk th=
an
the earth, the oxidation of the moon has, he thinks, extended much deeper t=
han
that of the earth, and her atmosphere and oceans have been exhausted in the
process. Both the earth and the moon, he maintains, have metallic nuclei, a=
nd
the streaks about Tycho and Copernicus, and some other lunar craters, may be
dikes of pure and shining metal, which have escaped oxidation owing to the
comparatively small supply of lunar oxygen. Upon this theory Aristarchus mu=
st
be a metallic mountain.
Clavius (11) is one of the most impressive of =
all
the lunar formations. There probably does not exist anywhere upon the earth=
so
wild a scene upon a corresponding scale of grandeur. Of course, its details=
are
far beyond the reach of the instrument we are supposed to be using, and yet=
, even
with a field-glass, or a powerful opera-glass, some of its main features are
visible. It is represented in our picture of the half-moon, being the lowest
and largest of the ring-like forms seen at the inner edge of the illuminated
half of the disk; the rays of the rising sun touching the summits of some of
the peaks in its interior have brought them into sight as a point of light,=
and
at the same time, reaching across the gulf within, have lighted up the high=
er
slopes of the great mountain-wall on the farther or eastern side of the
crater-valley, making it resemble a semicircle of light projecting into the
blackness of the still unilluminated plains around it. I should advise ever=
y reader
to take advantage of any opportunity that may be presented to him to see
Clavius with a powerful telescope when the sun is either rising or setting =
upon
it. Neison has given a spirited description of the scene, as follows:
The
sunrise on Clavius commences with the illumination of a few peaks on the western wall, but soon rapidly e=
xtends
along the whole wall of Clavius, =
which
then presents the appearance of a great double bay of the dark night-side of the moon penetra=
ting
so deep into the illuminated port=
ion as
to perceptibly blunt the southern horn to the naked eye. Within the dark bay some sma=
ll,
bright points soon appear--the su=
mmits
of the great ring-plains within--followed shortly by similar light-points near the center=
, due
to peaks on the walls of the smal=
ler
ring-plains, these light-islands gradually widening and forming delicate rings of light in the =
dark
mass of shadow still enveloping t=
he
floor of Clavius. Far in the east then dimly appear a few scarcely perceptible points, rapidly
widening into a thin bright line,=
the
crest of the great southeastern wall of Clavius, the end being still lost far within the night-s=
ide of
the moon. By the period the extre=
me
summit of the lofty wall of Clavius on the east becomes distinct, fine streaks of light begin to
extend across the dark mass of sh=
adow
on the interior of Clavius, from the light breaking through some of the passes on the west wall and
illuminating the interior; and th=
ese
streaks widen near the center and form illuminated spots on the floor, when both east and west it still=
lies
deeply immersed in shadow, strong=
ly
contrasting with the now brightly illuminated crest of the lofty east wall and the great ci=
rcular
broad rings of light formed by the
small ring-plains within Clavius. The illumination of the interior of Clavius now proceeds ra=
pidly,
and forms a magnificent spectacle=
: the
great, brightly illuminated ring-plains on the interior, with their floors still total=
ly
immersed in shadow; the immense s=
teep
line of cliffs on the east and southeast are now brilliantly illuminated, though the ent=
ire
surface at their base is still im=
mersed
in the shades of night; and the great peaks on the west towering above the floor are thrown str=
ongly
into relief against the dark shad=
ow
beyond them.
Newton (12) is the deepest of the great
crateriform chasms on the moon. Some of the peaks on its walls rise twenty-=
four
thousand feet above the interior gulf. Its shadow, and those of its gigantic
neighbors--for the moon is here crowded with colossal walls, peaks, and
craters--may be seen breaking the line of sunlight below Clavius, in our il=
lustration.
I have just spoken of these great lunar formations as chasms. The word desc=
ribes
very well the appearance which some of them present when the line separating
day and night on the moon falls across them, but the reader should not be l=
ed
by it into an erroneous idea of their real character. Such formations as
Newton, which is one hundred and forty miles long by seventy broad, may more
accurately be described as vast depressed plains, generally containing peaks
and craters, which are surrounded by a ring of steep mountains, or
mountain-walls, that rise by successive ridges and terraces to a stupendous
height.
The double chain of great crater-plains reachi=
ng
half across the center of the moon contains some of the grandest of these
strange configurations of conjoined mountain, plain, and crater. The names =
of the
principal ones can be learned from the map, and the reader will find it very
interesting to watch them coming into sight about first quarter, and passing
out of sight about third quarter. At such times, with a field-glass, some of
them look like enormous round holes in the inner edge of the illuminated ha=
lf
of the moon. Theophilus (23), Cyrillus (24), and Catharina (25), are three =
of
the finest walled plains on the moon--Theophilus, in particular, being a
splendid specimen of such formations. This chain of craters may be seen rap=
idly
coming into sunlight at the edge of the Sea of Nectar, in our picture of
"Sunrise on the Sea of Serenity," etc. The Altai Mountains (26) a=
re a
line of lofty cliffs, two hundred and eighty miles in length, surmounting a
high table-land.
The Caucasus Mountains (38) are a mass of
highlands and peaks, which introduce us to a series of formations resembling
those of the mountainous regions of the earth. The highest peak in this ran=
ge
is about nineteen thousand feet. Between the Caucasus and the Apennines (44)
lies a level pass, or strait, connecting the Sea of Serenity with the Sea of
Showers. The Apennines are the greatest of the lunar mountain-chains, exten=
ding
some four hundred and sixty miles in length, and containing one peak twenty=
-one
thousand feet high, and many varying from twelve thousand to nearly twenty
thousand. It will thus be seen that the Apennines of the earth sink into
insignificance in comparison with their gigantic namesakes on the moon. As =
this
range runs at a considerable angle to the line of sunrise, its high peaks a=
re
seen tipped with sunlight for a long distance beyond the generally illumina=
ted
edge about the time of first quarter. Even with the naked eye the sun-touch=
ed
summits of the lunar Apennines may at that time be detected as a tongue of
light projecting into the dark side of the moon. The Alps (41) are another
mountain-mass of great elevation, whose highest peak is a good match for the
Mont Blanc of the earth, after which it has been named.
Plato (42) is a very celebrated dark and level
plain, surrounded by a mountain-ring, and presenting in its interior many
puzzling and apparently changeable phenomena which have given rise to much =
speculation,
but which, of course, lie far beyond the reach of opera-glasses. Plato is s=
een
in the picture of "Sunrise on Clavius," etc., on page 133, being =
the
second ring from the top.
If Ariosto had had a telescope, we might have
suspected that it was this curious plain that he had in mind when he descri=
bed
that strange valley in the moon, in which was to be found everything that w=
as
lost from the earth, including lost wits; and where the redoubtable knight
Astolpho, having been sent in search of the missing wit of the great Orland=
o,
was astonished to find what he sought carefully preserved in a vial along w=
ith
other similar vials belonging to many supposedly wise people of the earth, =
whom
nobody suspected of keeping a good part of their sapience in the moon.
Copernicus (46) is the last of the lunar
formations that we shall describe. It bears a general resemblance to Tycho,=
and
is slightly greater in diameter; it is, however, not quite so deep. It has a
cluster of peaks in the center, whose tops may be detected with a field-gla=
ss, as
a speck of light when the rays of the morning sun, slanting across the vall=
ey,
illuminate them while their environs are yet buried in night. Copernicus is=
the
center of a system of light-streaks somewhat resembling those of Tycho, but=
very
much shorter.
We must not dismiss the moon without a few wor=
ds
as to its probable condition. It was but natural, after men had seen the
surface of the moon diversified with hills and valleys like another earth, =
that
the opinion should find ready acceptance that beings not unlike ourselves m=
ight
dwell upon it. Nothing could possibly have been more interesting than the
realization of such a fancy by the actual discovery of the lunar inhabitant=
s,
or at least of unmistakable evidence of their existence. The moon is so nea=
r to
the earth, as astronomical distances go, and the earth and the moon are so
intimately connected in the companionship of their yearly journey around the
sun, and their greater journey together with the sun and all his family,
through the realms of space, that we should have looked upon the lunar
inhabitants, if any had existed, as our neighbors over the way--dwelling, t=
o be
sure, upon a somewhat more restricted domain than ours, vassals of the eart=
h in
one sense, yet upon the whole very respectable and interesting people, with=
whom
one would be glad to have a closer acquaintance. But, alas! as the powers of
the telescope increased, the vision of a moon crowded with life faded, unti=
l at
last the cold fact struck home that the moon is, in all probability, a froz=
en
and dried-up globe, a mere planetary skeleton, which could no more support =
life
than the Humboldt glacier could grow roses. And yet this opinion may go too
far. There is reason for thinking that the moon is not absolutely airless, =
and,
while it has no visible bodies of water, its soil may, after all, not be
entirely arid and desiccated. There are observations which hint at visible
changes in certain spots that could possibly be caused by vegetation, and t=
here
are other observations which suggest the display of electric luminosity in =
a rarefied
atmosphere covering the moon. To declare that no possible form of life can
exist under the conditions prevailing upon the lunar surface would be saying
too much, for human intelligence can not set bounds to creative power. Yet,
within the limits of life, such as we know them, it is probably safe to ass=
ert
that the moon is a dead and deserted world. In other words, if a race of be=
ings
resembling ourselves, or resembling any of our contemporaries in terrestrial
life, ever existed upon the moon, they must long since have perished. That =
such
beings may have existed, is possible, particularly if it be true, as genera=
lly
believed, that the moon once had a comparatively dense atmosphere and water
upon its surface, which have now, in the process of cooling of the lunar gl=
obe,
been withdrawn into its interior. It certainly does not detract from the
interest with which we study the rugged and beautiful scenery of the moon to
reflect that if we could visit those ancient sea-bottoms, or explore those
glittering mountains, we might, perchance, find there some remains or memen=
tos
of a race that flourished, and perhaps was all gathered again to its father=
s,
before man appeared upon the earth.
That slight physical changes, such as the down=
fall
of mountain-walls or crater-cones, still occasionally occur upon the moon, =
is
an opinion entertained by some selenographers, and apparently justified by =
observation.
The enormous changes of temperature, from burning heat under a cloudless su=
n to
the freezing cold of space at night with no atmospheric blanket to retain h=
eat
(which has generally been assumed to be the condition of things on the moon=
),
would naturally exert a disintegrating effect upon the lunar rocks. But the=
question
is now in dispute whether the surface of the moon ever rises above the free=
zing-point
of water, even under a midday sun.
Mankind has always been a little piqued by the
impossibility of seeing the other side of the moon, and all sorts of odd
fancies have been indulged in regard to it. Among the most curious is the
ancient belief that the souls of the good who die on earth are transported =
to
that side of the moon which is turned away from the earth; while the souls =
of
the wicked sojourn on this side, in full view of the scene of their evil de=
eds.
The visible side of the moon--with its tremendous craters, its yawning chas=
ms,
its frightful contrasts of burning sunshine and Cimmerian darkness, its air=
less
and arid plains and dried-up sea-bottoms exposed to the pitiless cold of op=
en
space, and heated, if heated at all, by scorching sunbeams as fierce as nak=
ed
flame--would certainly appear to be in a proper condition to serve as a
purgatory. But we have no reason to think that the other side is any better=
off
in these respects. In fact, the glimpses that we get of it around the corne=
rs,
so to speak, indicate that the whole round globe of the moon is as ragged, =
barren,
and terrible as that portion of it which is turned to our view.
THE PLANETS.--In attempting to view the planets
with an opera-glass, too much must not be expected; and yet interesting vie=
ws
can sometimes be obtained. The features of their surfaces, of course, can n=
ot
be detected even with a powerful field-glass, but the difference between th=
e appearance
of a large planet and that of the stars will at once strike the observer.
Mercury, which, on account of its nearness to the sun and its rapid changes=
of
place, comparatively few persons ever see, can perhaps hardly be called an
interesting object for an opera-glass, and yet the beauty of the planet is
greatly increased when viewed with such aid. Mercury is brilliant enough to=
be
readily distinguishable, even while the twilight is still pretty bright; an=
d I
have had most charming views of the shy planet, glittering like a globule of
shining metal through the fading curtain of a winter sunset.
Venus is, under favorable circumstances, a very
interesting planet for opera-glass observations. The crescent phase can be =
seen
with a powerful glass near inferior conjunction, and, even when the form of=
the
planet can not be discerned, its exceeding brilliancy makes it an attractiv=
e object.
The flood of light which Venus pours forth, and which is so dazzling that it
baffles the best telescopes, to a greater or less extent, in any effort to
descry the features of that resplendent disk, is evidently reflected from a
cloud-burdened atmosphere. While these clouds render the planet surprisingly
lustrous to our eyes, they must, of course, keep the globe beneath them mos=
t of
the time in shadow. It is a source of keen regret that the surface of Venus=
can
not be seen as clearly as that of Mars, for, a priori, there is rather more
reason to regard Venus as possibly an inhabited world than any other of the=
Earth's
sister planets, not excepting Mars. Still, even if we could plainly make out
the presence of oceans and continents on Venus, that fact would hardly be a=
ny
better indication of the possibility of life there than is furnished by the
phenomena of its atmosphere. It is an interesting reflection that in admiri=
ng
the brilliancy of this splendid planet the light that produces so striking =
an
effect upon our eyes has but a few minutes before traversed the atmosphere =
of a
distant world, which, like our own air, may furnish the breath of life to
millions of intelligent creatures, and vibrate with the music of tongues
speaking languages as expressive as those of the earth.
Mars, being both more distant and smaller than
Venus, does not present so splendid a scene, and yet when it is at or near
opposition it is a superb object even for an opera-glass, its deep
reddish-yellow color presenting a fine contrast to that of most of the star=
s.
It can often be seen in conjunction with, or near to, the moon and stars, a=
nd
the beauty of these phenomena is in some cases greatly enhanced by the use =
of a
glass. To find Mars (and the same remark applies to the other planets), take
its right ascension and declination for the required date from the Nautical
Almanac, and then mark its place upon a planisphere or any good star-map. T=
his
planet is at the present time (1888) slowly drawing nearer to the earth at =
each
opposition, and in 1892 it will be closer to us than at any time since 1877,
when its two minute satellites were discovered. It will consequently grow
brighter every year until then. How splendidly it shines when at its nearest
approach to the earth may be inferred from the fact that in 1719 it was so
brilliant as actually to cause a panic. This was doubtless owing to its
peculiar redness. I well remember the almost startling appearance which the
planet presented in the autumn of 1877. Mars is especially interesting beca=
use
of the apparently growing belief that it may be an inhabited world, and bec=
ause
of certain curious markings on its surface that can only be seen under favo=
rable
conditions. The recent completion of the great Lick telescope and other lar=
ge
glasses, and the approach of the planet to a favorable opposition, give rea=
son
to hope that within the next few years a great deal of light will be cast u=
pon
some of the enigmatical features of Mars's surface.
Jupiter, although much more distant than Mars,=
is
ordinarily a far more conspicuous phenomenon in the sky on account of his v=
ast
bulk. His interest to observers with an opera-glass depends mainly upon his
four moons, which, as they circle about him, present a miniature of the sol=
ar system.
With a strong opera-glass one or two of Jupiter's little family of moons may
occasionally be caught sight of as excessively minute dots of light half-hi=
dden
in the glare of the planet. If you succeed under favorable circumstances in
seeing one of these moons with your glass, you will be all the more astonis=
hed
to learn that there are several apparently well-authenticated instances of =
one
of the moons of Jupiter having been seen with the naked eye.
With a field-glass, however, you will have no
difficulty in seeing all of the moons when they are properly situated. If y=
ou
miss one or more of them, you may know that it is either between you and the
planet, or behind the planet, or buried in the planet's shadow, or else so
close to the planet as to be concealed by its radiance.
It will be best for the observer to take out of
the Nautical Almanac the "configurations of Jupiter's satellites"=
for
the evenings on which he intends to make his observations, recollecting that
the position of the whole system, as there given, is reversed, or presented=
as
seen with an astronomical telescope, which inverts objects looked at, as an=
opera-glass
does not. In order to bring the satellites into the positions in which he w=
ill
see them, our observer has only to turn the page in the Nautical Almanac
showing their configurations upside down.
Of course, since the motions of the satellites,
particularly of the inner ones, are very rapid, their positions are continu=
ally
changing, and their configurations are different every night. If the observ=
er
has any doubt about his identification of them, or thinks they may be littl=
e stars,
he has only to carefully note their position and then look at them again the
next evening. He may even notice their motion in the course of a single
evening, if he begins early and follows them for three or four hours. It is
impossible to describe the peculiar attractions of the scene presented by t=
he
great planet and his four little moons on a serene evening to an observer a=
rmed
with a powerful glass. Probably much of the impressiveness of the spectacle=
is
owing to the knowledge that those little points of light, shining now in a =
row and
now in a cluster, are actually, at every instant, under the government of t=
heir
giant neighbor and master, and that as we look upon them, obediently making
their circuits about him, never venturing beyond a certain distance away, we
behold a type of that gravitational mastery to which our own little planet =
is
subject as it revolves around its still greater ruler, the sun, to whose
control even Jupiter in his turn must submit.
The beautiful planet Saturn requires for the
observation of its rings magnifying powers far beyond those of the instrume=
nts
with which our readers are supposed to be armed. It would be well, however,=
for
the observer to trace its slow motion among the stars with the aid of the N=
autical
Almanac, and he should be able with a good field-glass to see, under favora=
ble
circumstances, the largest of its eight moons, Titan. This is equal in
brilliancy to an 8.5 magnitude star. Its position with respect to Saturn on=
any
given date can be learned from the Ephemeris.
It may appear somewhat presumptuous to place U=
ranus,
a planet which it required the telescope and the eye of a Herschel to disco=
ver,
in a list of objects for the opera-glass. But it must not be forgotten that
Uranus was seen certainly several, and probably many, times before Herschel=
's discovery,
being simply mistaken, on account of the slowness of its motion, for a fixed
star. When near opposition, Uranus looks as bright as a sixth-magnitude sta=
r,
and can be easily detected with the naked eye when its position is known. W=
ith
an opera-glass (and still more readily with a field-glass) this distant pla=
net
can be watched as it moves deliberately onward in its gigantic orbit. Its
passage by neighboring stars is an exceedingly interesting phenomenon, and =
it
is in this way that you may recognize the planet.
On the evening of May 29, 1888, I knew, from t=
he
co-ordinates given in the Nautical Almanac, that Uranus was to be found a s=
hort
distance east of Mars, which was then only a few degrees from the well-known
star Gamma Virginis. Accordingly, I turned my opera-glass upon Mars, and at=
once
saw a star in the expected position, which I knew was Uranus. But there were
other small stars in the field, and, supposing I had not been certain which=
was
Uranus, how could I have recognized it? The answer is plain: simply by watc=
hing
for a night or two to see which star moved. That star would, of course, be
Uranus. The accompanying cuts will show the motions of Mars and Uranus with
respect to neighboring stars at that time, and will serve as an example of =
the
method of distinguishing a planet from the fixed stars by its change of pla=
ce.
In the first cut we have the two planets and three neighboring stars as they
appeared on May 29th. These stars were best seen with a field-glass, althou=
gh
an opera-glass readily showed them.
On June 1st the relative positions of the plan=
ets
and stars were as shown in the second cut. A glance suffices to show that n=
ot
only Mars but Uranus also has shifted its position with respect to the thre=
e immovable
stars. This change of place alone would have sufficed to indicate the ident=
ity
of Uranus. To make sure, the inexperienced observer had only to continue his
observations a few nights longer.
On June 6th Mars and Uranus were in conjunctio=
n,
and their position, as well as that of the same set of three stars, is show=
n in
the third cut. It will be seen that while Mars had changed its place very m=
uch
more than Uranus, yet that the latter planet had now moved so far from its =
original
position on May 29th, that there could be no possibility that the merest ty=
ro
in star-gazing would fail to notice the change. Whenever the observer sees =
an
object which he suspects to be a planet, he can satisfy himself of its iden=
tity
by making a series of little sketches like the above, showing the position =
of
the suspected object on successive evenings, with respect to neighboring st=
ars.
The same plan suffices to identify the larger planets, in the case of which=
no
glass is necessary. The observer can simply make a careful estimate by the =
naked
eye of the supposed planet's distance and bearing from large stars near it,=
and
compare them with similar observations made on subsequent evenings.
THE SUN.--That spots upon the sun may be seen =
with
no greater optical aid than that of an opera-glass is perhaps well known to
many of my readers, for during the past ten years public attention has been
drawn to sun-spots in an especial manner, on account of their supposed conn=
ection
with meteorology, and in that time there have been many spots upon the solar
disk which could not only be seen with an opera-glass, but even with the
unassisted eye. At present (1888) we are near a minimum period of sun-spots,
and the number to be seen even with a telescope is comparatively very small,
yet only a few days before this page was written there was a spot on the sun
large enough to be conspicuous with the aid of a field-glass. During the ti=
me
of a spot-maximum the sun is occasionally a wonderful object, no matter how=
small
the power of the instrument used in viewing it may be. Strings of spots of =
every
variety of shape sometimes extend completely across the disk. Our illustrat=
ion
shows the appearance of the sun, as drawn by the author on the 1st of
September, 1883. Every one of the spots and spot-groups there represented c=
ould
be seen with a good field-glass, and nearly all of them with an opera-glass=
.
As in all such cases, our interest in the
phenomena increases in proportion to our understanding of their significance
and their true scale of magnitude. In glancing from side to side of the sun=
's
disk, the eye ranges over a distance of more than 860,000 miles--not a mere
ideal distance, or an expanse of empty space, but a distance filled by an a=
ctual
and, so to speak, tangible body, whose diameter is of that stupendous
magnitude. One sees at a glance, then, the enormous scale on which these sp=
ots
are formed. The earth placed beside them would be but a speck, and yet they=
are
mere pits in the surface of the sun, filled perhaps with partially cooled
metallic vapors, which have been cast up from the interior, and are settling
back again. It is worth anybody's while to get a glimpse at a sun-spot if he
can, for, although he may see it merely as a black dot on the shining disk,=
yet
it represents the play of physical forces whose might and power are there e=
xercised
on a scale really beyond human comprehension. The imagination of Milton or
Dante would have beheld the mouth of hell yawning in a sun-spot.
In order to view the sun it is, of course,
necessary to contrive some protection for the eyes. This may be constructed=
by
taking two strips of glass four or five inches long and an inch wide, and
smoking one of them until you can without discomfort look at the sun through
it. Then place the two strips together, with the smoked surface inside--tak=
ing
care to separate them slightly by pieces of cardboard placed between the en=
ds--and
fasten the edges together with strips of paper gummed on. Then, by means of=
a
rubber band, fasten the dark glass thus prepared over the eye-end of your
opera-glass in such a way that both of the lenses are completely covered by=
it.
It will require a little practice to enable you to get the sun into the fie=
ld
of view and keep it there, and for this purpose you should assume a
posture--sitting, if possible--which will enable you to hold the glass very
steady. Then point the glass nearly in the direction of the sun, and move it
slowly about until the disk comes in sight. It is best to carefully focus y=
our instrument
on some distant object before trying to look at the sun with it.
As there is some danger of the shade-glass bei=
ng
cracked by the heat, especially if the object-glasses of the instrument are
pretty large, it would be well to get the strips of glass for the shade lar=
ge
enough to cover the object-end of the instrument instead of the eye-end. At=
a little
expense an optician will furnish you with strips of glass of complementary
tints, which, when fastened together, give a very pleasing view of the sun
without discoloring the disk. Dark red with dark blue or green answer very
well; but the color must be very deep. The same arrangement, of course, will
serve for viewing an eclipse of the sun.
A word, finally, about the messenger which bri=
ngs
to us all the knowledge we possess of the contents and marvels of space--li=
ght.
Without the all-pervading luminiferous ether, narrow indeed would be our ac=
quaintance
with the physical creation. This is a sympathetic bond by which we may conc=
eive
that intelligent creatures throughout the universe are united. Light tells =
us
of the existence of suns and systems so remote that the mind shrinks from t=
he
attempt to conceive their distance; and light bears back again to them a
similar message in the feeble glimmering of our own sun. And can any one
believe that there are no eyes out yonder to receive, and no intelligence to
interpret that message?
Sir Humphry Davy has beautifully expressed a
similar thought in one of his philosophical romances:
In J=
upiter
you would see creatures similar to those in Saturn, but with different powers of locomotion; in=
Mars
and Venus you would find races of
created forms more analogous to those belonging to the Earth; but in every part of the planetary syst=
em you
would find one character peculiar=
to
all intelligent natures, a sense of receiving impressions from light by various organs of vision,=
and
toward this result you can not but
perceive that all the arrangements and motions of the planetary bodies, their satellites and
atmospheres, are subservient. The
spiritual natures, therefore, that pass from system to system in progression toward power and knowledge
preserve at least this one invari=
able
character, and their intellectual life may be said to depend more or less upon the influence =
of
light.[G]
[G=
] See
"Consolations in Travel, or, the Last Days of a Philosopher"; Dialogue I.
Light is a result, and an expression, of the
energy of cosmical life. The universe lives while light exists. But when the
throbbing energies of all the suns are exhausted, and space is filled with
universal gloom, the light of intelligence must vanish too.
One can not read the wonderful messages of light--one can not study the sun, the moon, and the stars in any manner--without perceiving that the physical universe is enormously greater than he had thought, and that the creation, of which the Earth is an infinitesimal part, is almost infinitely more magnificent in actual magnitu= de than the imaginary domain which men of old times pictured as the dwelling-p= lace of the all-controlling gods; without feeling that he has risen to a higher = plane, and that his intellectual life has taken a nobler aim and a broader scope.<= o:p>