THE STARS OF WINTER.
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
constellations 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 precursors of the rising of Orion:
"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 hath aught to say
Of the night's measure or the slumbering winds."
The first glimpse we get of the hero of the sky 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 then
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 decoration upon the hero's right shoulder. Then come
into view the equally beautiful Rigel in the left foot, and the striking
row of three bright stars forming the Belt. 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 constellation
containing so many bright stars. It has two of the first magnitude,
Betelgeuse and Rigel; 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 magnitude, more than a dozen of the fourth,
and innumerable twinklers of smaller magnitudes, whose commingled
scintillations form a celestial illumination of singular splendor.
"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 flaming 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
constellations 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 stars 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, Capella, the Twins, Procyon, Sirius,
and Rigel mark the angles of a huge hexagon, while 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, not
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 summer 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 the 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
crusted snow, reflect the glitter of the living sky. In the pure frosty
air the stars seem splintered and multiplied indefinitely, and the
brighter ones shine with 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 detect 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, the 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 squares,
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 nothing of the little great world around him, stands
in the yawning silence of night and 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.
[Illustration: MAP. 18.]
Looking now at Map 18, we see the heavens as they 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
heavens 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 position of the different
constellations, and, having fixed this in his mind, he will be prepared
to study them in detail.
[Illustration: MAP 19.]
Let us now begin with Map No. 19, which shows us the constellations of
Eridanus, Lepus, Orion, and Taurus. Eridanus is a large though not very
conspicuous constellation, which is generally supposed to represent the
celebrated river now known as the Po. It has had different names among
different peoples, but the idea of a river, suggested by its long,
winding 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 chariot 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 reaches the bright star Gamma
([gamma]), where it bends sharply to the north, and then 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 again
and disappears beneath the horizon. Throughout the whole distance of
more than 100 deg. 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, after 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 stream,
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] squared. 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] squared 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] squared will
gradually 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 magnitude, 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] squared, and are fellow-voyagers of that wonderful star.
[Illustration: THE "GOLDEN HORNS" OF TAURUS.]
Having admired the star-groups of Eridanus, one 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 appropriately 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 herself
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 beautiful 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 horns 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 large a field-glass as he can obtain. With such a glass
their appearance almost makes 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 season--
"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. With an ordinary
glass, however, the observer will not find this star-sprinkled region
around the horns of Taurus as brilliant a spectacle as that presented 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 way. 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 star. 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 star 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 nebulae. This
is sometimes called the "Crab Nebula," from the long sprays of nebulous
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 object. 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 position shown in the cut, where the large star is
Zeta and the smaller ones are faint 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.
[Illustration: THE CRAB NEBULA.]
And now let us look at the Hyades, an assemblage 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 surprised 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-glass. The "brackish poet," of whose rhymes Admiral Smyth was so
fond, thus describes the Hyades:
"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 such 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 compare 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 Rigel 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 distances of which the ancients
could not conceive, have, at the same time, and equally, 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.
[Illustration: THE HYADES.]
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 point of the [V], is Gamma Tauri. The three brightest stars between
Epsilon and Gamma, 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. These 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 distance
between the two Thetas is about five and a half minutes of arc. These
measures 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-sight to endeavor to see these stars as doubles without
the aid of a glass. Persons 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"), 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 between
them in brightness, and the smaller star is only of magnitude 6.5, while
sixth-magnitude 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 the
unaided eye. It is a singular fact that many of the earliest writers
declare that only 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, Celaeno,
Electra, Taygeta, Asterope, and Maia. 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, like 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. They 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 part 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 human race in
the past, has been found to be directly related to the Pleiades. This
festival or rite, which has been discovered in various forms among the
ancient Hindoos, 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 Mexicans, 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. Among the savages
inhabiting Australia and the Pacific island groups a similar rite 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 with that mystery of
mysteries, the great Pyramid of Cheops. It has been found that 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, just 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 constellation 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 water 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 connected, as by common consent among
many nations, and in the most widely separated parts 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 such a
glass the scene is a remarkable one. Not only all of the "Seven
Sisters," 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 vision, and is always counted
among the naked-eye Pleiades, although it does not bear 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
pointing 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. About half-way between Taygeta and Electra, and
directly above the latter, is Celaeno.
[Illustration: THE PLEIADES.]
The naked-eye observer will probably find it difficult to decide which
he can detect the more easily, Celaeno or Pleione, while he will discover
that Asterope, although composed of two stars, as seen with a glass, is
so faint as to be much more difficult than either Celaeno 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
undergone 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 the 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, better to marry a plain mortal than a
god. Electra, too, who hid her eyes at the sight 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 regard those
changes in the brightness of the Pleiades which are based upon
tradition, there is no doubt that well-attested changes have taken place
in the comparative brilliancy of stars in this cluster since astronomy
became an exact science.
Observations of the proper motions of the Pleiades have shown that there
is an actual physical connection between them; that they 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 Maedler as the central sun around
which 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 vast nebulous mass is represented near the
stars Atlas and Pleione. This has since 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 inclined to
doubt their actual existence. Within the past few years astronomical
photography, 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 star 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 form
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 appear all the more life-like:
"Many a night I saw the Pleiads, rising through the mellow shade,
Glitter like _a swarm of fire-flies tangled in a silver braid_."
The reader should not expect to be able to see the nebulae in the
Pleiades with an opera-glass. I have thought it proper to mention 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 more interesting
and wonderful. They have found that there are many nebulous masses
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, shall cast his eyes in vain
To find a brighter sign in all the heaven."
To the naked eye, to the opera-glass, and to the telescope, Orion is
alike a mine of wonders. This great constellation embraces almost every
variety of interesting phenomena that the heavens contain. Here we have
the grandest of the nebulae, some of the largest and most beautifully
colored stars, star-streams, star-clusters, nebulous stars, variable
stars. I have already mentioned the positions of the principal stars in
the imaginary figure of the great hunter. I may add that his upraised
arm and club are represented by the stars seen in the map above Alpha
([alpha]) or Betelgeuse, one of which is marked Nu ([nu]), and another,
in the knob of the club, Chi ([chi]). I have 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
third order, which seems to represent a type of suns in which the
process of cooling, and the formation of an absorptive envelope or
shell, have gone on so far that we may regard them as approaching the
point of extinction. Rigel, on the other 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 two 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 back 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 illuminate space when
Rigel itself is growing dim.
[Illustration: THE SWORD OF ORION AND THE GREAT NEBULA.]
Turn your glass upon the three stars forming the 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 turn your
attention to different parts of the field. Sweep all around the Belt and
also between the Belt and Gamma ([gamma]) or Bellatrix. According to the
old astrologers, women born under the influence of the star Bellatrix
were lucky, and provided with good tongues. Of course, this was
fortunate for their husbands too!
Below the Belt will be seen a short row of stars hanging downward and
representing the sword. In the middle of this row is the 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
surrounding 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 Sword of Orion shows its appearance with a good
field-glass. With such a glass several 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 above the nebula. No difficulty
will be encountered in separating these stars with 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
found rather elusive as individuals, though easily glimpsed as a whole.
Of the great 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 distance. 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 operation 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 be a group of stars like some of those which we see in
the heavens, and whose common 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 west 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, after 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 seen
is not the only one there. A still smaller star, which had before been
completely hidden, will now be perceived. I may add that, with
telescopes, Rigel is one 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 will find some
interesting combinations, and the star marked on the map [pi]^6 will
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 stars, 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 by 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
comers. As becomes the splendor of his constellation, Orion is a
tremendous hero of antiquity, although it must be confessed that his
history is somewhat shadowy 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.
[Illustration: MAP 20.]
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 magnitude, and from
that varies down to the ninth, we could hardly hope to see its color
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 to 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 does it
injustice, since no other star of that magnitude is at all comparable
with it. Sirius, in fact, stands in a class by itself as the brightest
star in the sky. Its light is white, with a shade of green, which
requires close watching 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
impossible, though it is highly improbable, that Sirius has changed
color.
So intimately was Sirius connected in the minds 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 immediate 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 minute 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] squared there is a remarkable
array of minute stars, as shown in the accompanying cut. One never sees
stars arranged in streams or rows, like these, without an irresistible
impression that the arrangement can not be accidental; 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 do
we seem to be from understanding the meaning of the universe!
[Illustration: DELTA CANIS MAJORIS AND ITS NEIGHBORS.]
The extraordinary size and brilliancy of Sirius might naturally enough
lead one to suppose that it is the nearest of the stars, and such it was
once believed to be. Observations of stellar parallax, however, show
that this was a mistake. The distance of Sirius is so great that no
satisfactory 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. Then, 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, 288,000,000,000 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 = 72
times as brilliantly as the sun. If we adopt Wollaston's estimate
of the light of Sirius, as compared with that 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
spectrum indicates that its intrinsic brightness, surface for surface,
is much superior to the sun's, it is probable that our estimate of the
star's actual brilliancy, 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 to 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
lengthened 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. Good 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 greater
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 measurable, 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,
brought the hidden star into view. The suggestion that it may shine by
reflected light from Sirius has been made. In that case it must, of
course, be a planet, but 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 size to more than a million
earths! But, as was remarked of the faint stars in Alpha Capricornis, it
is probable that the hypothesis of reflected light is not the true one.
More probably the companion of Sirius shines with light of its own,
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 discoveries made since then:
"At all 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 hero of his extraordinary
story of "Micromegas" came from an imaginary planet 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 planet 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 twenty 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 gone 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 himself would
have been a fit subject for microscopic examination. But, however much
we may doubt the stature of Voltaire's visitor from Sirius, we can not
doubt the soundness of the conclusion at which he arrived, after having,
by an ingenious arrangement, succeeded in holding a conversation with
some earthly philosophers under his microscope, namely, that these
infinitely little creatures possessed a pride that was almost infinitely
great.
East and south of Canis Major, which, by-the-way, is said to represent
one of Orion's hounds, is part of the constellation Argo, which stands
for the ship in which Jason sailed in search of the golden fleece. 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 lost. Note the two stars [zeta] and [pi] near the lower
edge of the map, then sweep slowly over the space lying between them.
About half-way your attention will be arrested by a remarkable stellar
arrangement, in which a beautiful half-circle 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 eye can not see.
Just below the star [eta], in Canis Major, is another fine group. 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 the 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, are 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
constellations lie either in the Milky-Way or along its borders.
Cassiopeia, as we saw, sits 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 shoulders of Orion as between
starry banks; the peerless Sirius hangs like a gem pendent from the
celestial girdle. In the southern hemisphere we should find the
beautiful 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 stars 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 dome 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 region
around the stars 8, 13, and 17 will be found particularly rich, and the
cluster 2^7 shows well with a strong glass. Look also at the cluster 50
M, and compare 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 that
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 acquaintances never grow wearisome. Their interest for us
is as fathomless as the deeps of space in which they shine. The man
never yet lived whose mind could comprehend the full meaning of the
wondrous messages that they flash to us upon the wings of light. As we
watch them in their courses, the true music of the spheres comes to our
listening ears, the chorus of creation--faint with distance, for it is
by slow approaches 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 not be afraid to become a star-gazer. The human
mind can find no higher exercise. He who studies the stars will
discover--
"An endless fountain of immortal drink
Pouring unto us from heaven's brink."