"The heavens number out the glory of the strong God."--DAVID.
[Page 194]
Richter says that "an angel once took a man and stripped him of
his flesh, and lifted him up into space to show him the glory of
the universe. When the flesh was taken away the man ceased to be
cowardly, and was ready to fly with the angel past galaxy after
galaxy, and infinity after infinity, and so man and angel passed
on, viewing the universe, until the sun was out of sight--until
our solar system appeared as a speck of light against the black
empyrean, and there was only darkness. And they looked onward,
and in the infinities of light before, a speck of light appeared,
and suddenly they were in the midst of rushing worlds. But they
passed beyond that system, and beyond system after system, and
infinity after infinity, until the human heart sank, and the man
cried out: 'End is there none of the universe of God?' The angel
strengthened the man by words of counsel and courage, and they flew
on again until worlds left behind them were out of sight, and specks
of light in advance were transformed, as they approached them, into
rushing systems; they moved over architraves of eternities, over
pillars of immensities, over architecture of galaxies, unspeakable in
dimensions and duration, and the human heart sank again and called
ont: 'End is there none of the universe of God?' And all the stars
echoed the question with amazement: 'End is there none of the universe
of God?' And this echo found no answer. They moved on again past
immensities of immensities, and eternities of eternities, until
in the dizziness of uncounted galaxies the human heart sank for
the last time, and called out: 'End is there none of the universe
of God?' And again all the stars repeated the question, and the
angel answered: 'End is there none of the universe of God. Lo,
also, there is no beginning.'"
[Page 195]
X.
_THE OPEN PAGE OF THE HEAVENS._
The Greeks set their mythological deities in the skies, and read
the revolving pictures as a starry poem. Not that they were the
first to set the blazonry of the stars as monuments of their thought;
we read certain allusions to stars and asterisms as far back as
the time of Job. And the Pleiades, Arcturus, and Orion are some of
the names used by Him who "calleth all the stars by their names,
in the greatness of his power." Homer and Hesiod, 750 B.C., allude
to a few stars and groups. The Arabians very early speak of the
Great Bear; but the Greeks completely nationalized the heavens.
They colonized the earth widely, but the heavens completely; and
nightly over them marched the grand procession of their apotheosized
divinities. There Hercules perpetually wrought his mighty labors
for the good of man; there flashed and faded the changeful star
Algol, as an eye in the head of the snaky-haired Medusa; over them
flew Pegasus, the winged horse of the poet, careering among the
stars; there the ship Argo, which had explored all strange seas
of earth, nightly sailed in the infinite realms of heaven; there
Perseus perpetually killed the sea-monster by celestial aid, and
perpetually won the chained Andromeda for his bride. Very evident
was their recognition of divine help: equally evident was [Page 196]
their assertion of human ability and dominion. They gathered the
illimitable stars, and put uncountable suns into the shape of the
Great Bear--the most colossal form of animal ferocity and
strength--across whose broad forehead imagination grows weary in
flying; but they did not fail to put behind him a representative of
themselves, who forever drives him around a sky that never sets--a
perpetual type that man's ambition and expectation correspond to
that which has always been revealed as the divine.
The heavens signify much higher power and wisdom to us; we retain the
old pictures and groupings for the convenience of finding individual
stars. It is enough for the astronomer that we speak of a star as
situated right ascension 13' 45", declination 88° 40'. But for
most people, if not all, it is better to call it Polaris. So we
might speak of a lake in latitude 42° 40', longitude 79° 22', but
it would be clearer to most persons to say Chatauqua. For exact
location of a star, right ascension and declination must be given;
but for general indication its name or place in a constellation
is sufficiently exact. The heaven is rather indeterminably laid
out in irregular tracts, and the mythological names are preserved.
The brightest stars are then indicated in order by the letters of
the Greek alphabet--Alpha (a), Beta (b), Gamma (g), etc. After
these are exhausted, the Roman alphabet is used in the same manner,
and then numbers are resorted to; so that the famous star 61 Cygni
is the 111th star in brightness in that one constellation. An
acquaintance with the names, peculiarities, and movements of the
stars visible at different seasons of the year is an unceasing
source of pleasure. It [Page 197] is not vision alone that is
gratified, for one fine enough may hear the morning stars sing
together, and understand the speech that day uttereth unto day, and
the knowledge that night showeth unto night. One never can be alone
if he is familiarly acquainted with the stars. He rises early in the
summer morning, that he may see his winter friends; in winter, that
he may gladden himself with a sight of the summer stars. He hails
their successive rising as he does the coming of his personal
friends from beyond the sea. On the wide ocean he is commercing with
the skies, his rapt soul sitting in his eyes. Under the clear skies
of the East he hears God's voice speaking to him, as to Abraham, and
saying, "Look now toward the heavens, and tell the number of the
stars, if thou be able to number them."
A general acquaintance with the stars will be first attempted;
a more particular knowledge afterward. Fig. 67 (page 201) is a
map of the circumpolar region, which is in full view every clear
night. It revolves daily round Polaris, its central point. Toward
this star, the two end stars of the Great Dipper ever point, and
are in consequence called "the Pointers." The map may be held toward
the northern sky in such a position as the stars may happen to be.
The Great Bear, or Dipper, will be seen at nine o'clock in the
evening above the pole in April and May; west of the pole, the
Pointers downward, in July and August; close to the north horizon
in October and November; and east of the pole the Pointers highest,
in January and February. The names of such constantly visible stars
should be familiar. In order, from the end of the tail of the Great
Bear, we have Benetnasch ae, Mizar z, Little Alcor close to it,
[Page 198] Alioth, e Megrez, d at the junction, has been growing
dimmer for a century, Phad, g Dubhe and Merak. It is best to get
some facility at estimating distances in degrees. Dubhe and Merak,
"the Pointers," are five degrees apart. Eighteen degrees forward of
Dubhe is the Bear's nose; and three pairs of stars, fifteen degrees
apart, show the position of the Bear's three feet. Follow "the
Pointers" twenty-nine degrees from Dubhe, and we come to the
pole-star. This star is double, made of two suns, both appearing as
one to the naked eye. It is a test of an excellent three-inch
telescope to resolve it into two. Three stars beside it make the
curved-up handle of the Little Dipper of Ursa Minor. Between the two
Bears, thirteen degrees from Megrez, and eleven degrees from Mizar,
are two stars in the tail of the Dragon, which curves about to
appropriate all the stars not otherwise assigned. Follow a curve of
fifteen stars, doubling back to a quadrangle from five to three
degrees on a side, and thirty-five degrees from the pole, for his
head. His tongue runs out to a star four degrees in front. We shall
find, hereafter, that the foot of Hercules stands on this head. This
is the Dragon slain by Cadmus, and whose teeth produced such a crop
of sanguinary men.
The star Thuban was once the pole-star. In the year B.C. 2300 it
was ten times nearer the pole than Polaris is now. In the year
A.D. 2100 the pole will be within 30' of Polaris; in A.D. 7500,
it will be at a of Cepheus; in A.D. 13,500, within 7° of Vega; in
A.D. 15,700, at the star in the tongue of Draco; in A.D. 23,000,
at Thuban; in A.D. 28,000, back to Polaris. This indicates no change
in the position of the dome [Page 199] of stars, but a change in the
direction of the axis of the earth pointing to these various places
as the cycles pass. As the earth goes round its orbit, the axis,
maintaining nearly the same direction, really points to every part
of a circle near the north star as large as the earth's orbit, that
is, 185,000,000 miles in diameter. But, as already shown, that
circle is too small to be discernible at our distance. The wide
circle of the pole through the ages is really made up of the
interlaced curves of the annual curves continued through 25,870
years. The stem of the spinning top wavers, describes a circle, and
finally falls; the axis of the spinning earth wavers, describes a
circle of nearly 28,000 years, and never falls.
The star g Draconis, also called Etanin, is famous in modern astronomy,
because observations on this star led to the discovery of the
_aberration of light_. If we held a glass tube perpendicularly out
of the window of a car at rest, when the rain was falling straight
down, we could see the drops pass directly through. Put the car
in motion, and the drops would seem to start toward us, and the
top of the tube must be bent forward, or the drops entering would
strike on the backside of the tube carried toward them. So our
telescopes are bent forward on the moving earth, to enable the
entered light to reach the eye-piece. Hence the star does not appear
just where it is. As the earth moves faster in some parts of its
orbit than others, this aberration is sometimes greater than at
others. It is fortunate that light moves with a uniform velocity,
or this difficult, problem would be still further complicated.
The displacement of a star from this course is about 20".43.
[Page 200]
On the side of Polaris, opposite to Ursa Major, is King Cepheus,
made of a few dim stars in the form of the letter K. Near by is
his brilliant wife Cassiopeia, sitting on her throne of state.
They were the graceless parents who chained their daughter to a
rock for the sea-monster to devour; but Perseus, swift with the
winged sandals of Mercury, terrible with his avenging sword, and
invincible with the severed head of Medusa, whose horrid aspect of
snaky hair and scaly body turned to stone every beholder, rescues
the maiden from chains, and leads her away by the bands of love.
Nothing could be more poetical than the life of Perseus. When he
went to destroy the dreadful Gorgon, Medusa, Pluto lent him his
helmet, which would make him invisible at will; Minerva loaned
her buckler, impenetrable, and polished like a mirror; Mercury
gave him a dagger of diamonds, and his winged sandals, which would
carry him through the air. Coming to the loathsome thing, he would
not look upon her, lest he, too, be turned to stone; but, guided
by the reflection in the buckler, smote off her head, carried it
high over Libya, the dropping blood turning to serpents, which
have infested those deserts ever since.
[Illustration: Fig. 67.--Circumpolar Constellations. Always visible.
In this position.--January 20th, at 10 o'clock; February 4th, at
9 o'clock; and February 19th, at 8 o'clock.]
The human mind has always been ready to deify and throne in the
skies the heroes that labor for others. Both Perseus and Hercules
are divine by one parent, and human by the other. They go up and
down the earth, giving deliverance to captives, and breaking every
yoke. They also seek to purge away all evil; they slay dragons,
gorgons, devouring monsters, cleanse the foul places of earth,
and one of them so wrestles with death as to win a victim from his
grasp. Finally, by [Page 201] an ascension in light, they go up to
be in light forever. They are not ideally perfect. They right wrong
by slaying wrong-doers, rather than by being crucified themselves;
they are just murderers; but that only plucks the fruit from the
tree of evil. They never attempted to infuse a holy life. They
punished rather than regenerated. It must be confessed, also, that
they were not sinless. But they were the best saviors the race could
imagine, and are examples of that perpetual effort of the human mind
to incarnate a Divine Helper who shall labor and die for the good of
men.
[Page 202]
[Illustration: Fig. 68.--Algol is on the Meridian, 51° South of
Pole.--At 10 o'clock, December 7th; 9 o'clock, December 22d; 8
o'clock, January 5th.]
_Equatorial Constellations._
If we turn our backs on Polaris on the 10th of November, at 10
o'clock in the evening, and look directly overhead, we shall see
the beautiful constellation of Andromeda. Together with the square
of Pegasus, it makes another enormous dipper. The star a Alpheratz
is in her face, the three at the left cross her breast. b and the
two above mark the girdle of her loins, and g is in the foot. Perseus
is near enough for help; and Cetus, the sea-monster, is far enough
away to do no harm. Below, and east of Andromeda, is the Ram of
the golden fleece, recognizable by the three stars in an acute
triangle. The brightest is called Arietis, or Hamel. East of this
are the Pleiades, and the V-shaped Hyades in Taurus, or the Bull.
The Pleiades rise about 9 o'clock on the evening of the 10th of
September, and at 3 o'clock A.M. on June 10th.
[Page 203]
[Illustration: Fig. 69.--Capella (45° from the Pole) and Rigel
(100°) are on the Meridian at 8 o'clock February 7th, 9 o'clock
January 22d, and at 10 o'clock January 7th.]
Fig. 69 extends east and south of our last map. It is the most
gorgeous section of our heavens. (See the Notes to the Frontispiece.)
Note the triangle, 26° on a side, made by Betelguese, Sirius, and
Procyon. A line from Procyon to Pollux leads quite near to Polaris.
Orion is the mighty hunter. Under his feet is a hare, behind him
are two dogs, and before him is the rushing bull. The curve of
stars to the right of Bellatrix, g, represents his shield of the
Nemean lion's hide. The three stars of his belt make a measure
3° long; the upper one, Mintaker, is less than 30' south of the
equinoctial. The ecliptic passes between Aldebaran and the Pleiades.
Sirius rises about 9 o'clock P.M. on the 1st of December, and about
4 o'clock A.M. on the 16th of August. Procyon rises about half an
hour earlier.
[Page 204]
[Illustration: Fig. 70--Regulus comes on the Meridian, 79° south
from the Pole, at 10 o'clock March 23d, 9 o'clock April 8th, and
at 8 o'clock April 23d.]
Fig. 70 continues eastward. Note the sickle in the head and neck
of the Lion. The star b is Denebola, in his tail. Arcturus appears
by the word Bootes, at the edge of the map. These two stars make
a triangle with Spica, about 35° on a side. The geometric head of
Hydra is easily discernible east of Procyon: The star g in the
Virgin is double, with a period of 145 years. z is just above the
equinoctial. There is a fine nebula two-thirds of the way from d to
ae, and a little above the line connecting the two. Coma Berenices
is a beautiful cluster of faint stars. Spica rises at 9 o'clock on
the 10th of February, at 5 o'clock A.M. on the 6th of November.
[Page 205]
[Illustration: Fig. 7l.--Arcturus comes to the Meridian, 70° from
the Pole, at 10 o'clock May 25th, 9 o'clock June 9th, and at 8
o'clock June 25th.]
Fig. 71 represents the sky to the eastward and northward of the
last. A line drawn from Polaris and Benetnasch comes east of Arcturus
to the little triangle called his sons. Bootes drives the Great
Bear round the pole. Arcturus and Denebola make a triangle with
a, also called Cor Coroli, in the Hunting Dogs. This triangle, and
the one having the same base, with Spica for its apex, is called
the "Diamond of the Virgin." Hercules appears head down--a in the
face, b, g, d; in his shoulders, p; and ae; in the loins, t in the
knee, the foot being bent to the stars at the right. The Serpent's
head, making an X, is just at the right of the g of Hercules, and
the partial circle of the Northern Crown above. The head of Draco
is seen at b on the left of the map. Arcturus rises at 9 o'clock
about the 20th of February, and at 5 A.M. on the 22d of October;
Regulus 3h. 35m. Earlier.
[Page 206]
[Illustration: Fig. 72.--Altair comes to the Meridian, 82° from
the Pole, at 10 o'clock P.M. August 18th, at 9 o'clock September
2d, and at 8 o'clock September 18th.]
Fig. 72 portrays the stars eastward and southward. Scorpio is one
of the most brilliant and easily traced constellations. Antares, a,
in the heart, is double. In Sagittarius is the Little Milk-dipper,
and west of it the bended bow. Vega is at the top of the map. Near
it observe z, a double, and e, a quadruple star. The point to which
the solar system is tending is marked by the sign of the earth
below p; Herculis. The Serpent, west of Hercules, and coiled round
nearly to Aquila, is very traceable. In the right-hand lower corner
is the Centaur. Below, and always out of our sight, is the famous
a Centauri. The diamond form of the Dolphin is sometimes called
"Job's Coffin." The ecliptic passes close [Page 207] to b of
Scorpio, which star is in the head. Antares, in Scorpio, rises at 9
o'clock P.M. on May 9th, and at 5 o'clock A.M. on January 5th.
[Illustration: Fig. 73.--Fomalhaut comes to the Meridian, only 17°
from the horizon, at 8 o'clock November 4th.]
In Fig. 73 we recognize the familiar stars of Pegasus, which tell
us we have gone quite round the heavens. Note the beautiful cross
in the Swan. b in the bill is named Albireo, and is a beautiful
double to almost any glass. Its yellow and blue colors are very
distinct. The place of the famous double star 61 Cygni is seen. The
first magnitude star in the lower left-hand corner is Fomalhaut, in
the Southern Fish. a Pegasi is in the diagonal corner from Alpharetz,
in Andromeda. The star below Altair is b Aquilæ, and is called
Alschain; the one above is g Aquilæ, named Tarazed. This is not
a brilliant section of the sky. Altair rises at 9 o'clock on the
29th of May, and at 6 o'clock A.M. on the 11th of January.
[Page 208]
[Illustration: Fig. 74.--Southern Circumpolar Constellations invisible
north of the Equator.]
Fig. 74 gives the stars that are never seen by persons north of
the earth's equator. In the Ship is brilliant Canopus, and the
remarkable variable ae. Below it is the beautiful Southern Cross,
near the pole of the southern heavens. Just below are the two first
magnitude stars Bungala, a, and Achernar, b, of the Centaur. Such
a number of unusually brilliant stars give the southern sky an
unequalled splendor. In the midst of them, as if for contrast,
is the dark hole, called by the sailors the "Coal-sack," where
even the telescope reveals no sign of light. Here, also, are the
two Magellanic clouds, both easily discernible by the naked eye;
the larger two hundred times the apparent size of the moon, lying
between the pole and Canopus, and the other between Achernar and
the pole. The smaller cloud is only one-fourth the size of the
other. Both are mostly resolvable into groups of stars from the
fifth to the fifteenth magnitude.
[Page 209]
For easy out-door finding of the stars above the horizon at any
time, see star-maps at end of the book.
_Characteristics of the Stars._
Such a superficial examination of stars as we have made scarcely
touches the subject. It is as the study of the baptismal register,
where the names were anciently recorded, without any knowledge
of individuals. The heavens signify much more to us than to the
Greeks. We revolve under a dome that investigation has infinitely
enlarged from their estimate. Their little lights were turned by
clumsy machinery, held together by material connections. Our vast
worlds are connected by a force so fine that it seems to pass out
of the realm of the material into that of the spiritual. Animal
ferocity or a human Hercules could image their idea of power. Ours
finds no symbol, but rises to the Almighty. Their heavens were full
of fighting Orions, wild bulls, chained Andromedas, and devouring
monsters. Our heavens are significant of harmony and unity; all
worlds carried by one force, and all harmonized into perfect music.
All their voices blend their various significations into a personal
speaking, which says, "Hast thou not heard that the everlasting
God, the Lord, the creator of the ends of the earth, fainteth not,
neither is weary?" There is no searching of his understanding.
Lift up your eyes on high, and behold who hath created all these
things, that brought out their host by number, that calleth them
all by their names in the greatness of his power; for that he is
strong in power not one faileth.
[Page 210]
_Number._
We find about five thousand stars visible to the naked eye in the
whole heavens, both north and south. Of these twenty are of the
first magnitude, sixty-five of the second, two hundred of the third,
four hundred of the fourth, eleven hundred of the fifth, and three
thousand two hundred of the sixth. We think we can easily number
the stars; but train a six-inch telescope on a little section of the
Twins, where six faint stars are visible, and over three thousand
luminous points appear. The seventh magnitude has 13,000 stars;
the eighth, 40,000; the ninth, 142,000. There are 18,000,000 stars
in the zone called the Milky Way. When our eyes are not sensitive
enough to be affected by the light of far-off stars the tastimetre
feels their heat, and tells us the word of their Maker is true--"they
are innumerable."[*]
[Footnote *: _Telescopic Work._--Look at the Hyades and Pleiades
in Taurus. Notice the different colors of stars in them both. Find
the cluster Præsepe in Fig. 70, just a trifle above a point midway
between Procyon and Regulus. It is equally distant from Procyon and
a point a little below Pollux. Sweep along the Milky Way almost
anywhere, and observe the distribution of stars; in some places
perfect crowds, in others more sparsely scattered. Find with the
naked eye the rich cluster in Perseus. Draw a line from Algol to
a of Perseus (Fig. 67); turn at right angles to the right, at a
distance of once and four-tenths the first line a brightness will
be seen. The telescope reveals a gorgeous cluster.]
_Double and Multiple Stars._
If we look up during the summer months nearly overhead at the star
e Lyra, east of Vega (Fig. 72), we shall see with the naked eye
that the star appears a little [Page 211] elongated. Turn your
opera-glass upon it, and two stars appear. Turn a larger telescope
on this double star, and each of the components separate into two.
It is a double double star. We know that if two stars are near in
reality, and not simply apparently so by being in the same line of
sight, they must revolve around a common centre of gravity, or rush
to a common ruin. Eagerly we watch to see if they revolve. A few
years suffice to show them in actual revolution. Nay, the movement
of revolution has been decided before the companion star was
discovered. Sirius has long been known to have a proper motion, such
as it would have if another sun were revolving about it. Even the
direction of the unseen body could always be indicated. In February,
1862, Alvan Clark, artist, poet, and maker of telescopes (which
requires even greater genius than to be both poet and artist),
discovered the companion of Sirius just in its predicted place. As a
matter of fact, one of Mr. Clark's sons saw it first; but their fame
is one. The time of revolution of this pair is fifty years. But one
companion does not meet the conditions of the movements. Here must
also be one or more planets too small or dark to be seen. The double
star x in the Great Bear (see Fig. 70) makes a revolution in
fifty-eight years.
Procyon moves in an orbit which requires the presence of a companion
star, but it has as yet eluded our search. Castor is a double star;
but a third star or planet, as yet undiscovered, is required to
account for its perturbations. Men who discovered Neptune by the
perturbations of Uranus are capable of judging the cause of the
perturbations of suns. We have spoken of [Page 212] the whole orbit
of the earth being invisible from the stars. The nearest star in our
northern hemisphere, 61 Cygni, is a telescopic double star; the
constituent parts of it are forty-five times as far from each other
as the earth is from the sun, yet it takes a large telescope to show
any distance between the stars.[*]
[Footnote *: _Telescopic Work._--Only such work will be laid out
here as can be done by small telescopes of from two to four inch
object-glasses. The numbers in Fig. 75 correspond to those of the
table.
--------------------------------------------------------------------
| | | |Dist. of|Magni-| |
|No.| Name. | Fig. | Parts. |tudes.| Remarks. |
|---|------------|-------------|--------|------|---------------------|
| 1.| e Lyræ | 72 | 1' 56" | |Quadruple. |
| 2.| z Lyræ | 72 | 44 |5 & 6 |Topaz and green. |
| 3.| b Cygni | 73 | 34-1/2|3 & 6 |Yellow and blue. |
| 4.| 61 Cygni | 73 | 20 |5 & 6 |Nearest star but one.|
| 5.| Mizar | 67 | 14 |3 & 4 |Both white. |
| 6.| Polaris | 67 | 18-1/2|2 & 9 |Test object of eye |
| | | | | | and glass. |
| 7.| r Orionis |Frontispiece.| 7 |5 & 8 |Yellow and blue. |
| 8.| b Orionis | " | 9 |1 & 8 | Rigel. |
| 9.| d " | " | 10 |2 & 8 | Red and white. |
|10.| th " | " | | |Septuple. |
|11.| l " | " | 5 | |White and violet. |
|12.| s " | " A, B.| 11 |4 & 10|Octuple. |
|13.| Castor | 69 | 5-1/2|2 & 3 |White. |
|14.| Pollux | 69 | |Triple|Orange, gray, lilac. |
|15.| g Virginis | 70 | 5 |3 & 3 |Both yellow. |
--------------------------------------------------------------------
]
When g Virginis was observed in 1718 by Bradley, the component
parts were 7" asunder. He incidentally remarked in his note-book
that the line of their connection was parallel to the line of the
two stars Spica, or a and d Virginis. By 1840 they were not more
than 1" apart, and the line of their connection greatly changed.
The appearance of the star is given in Fig. 75 (15), commencing
at the left, for the years 1837 '38 '39 '40 '45 '50 '60 and '79.
also a conjectural [Page 213] orbit, placed obliquely, and the
position of the stars at the times mentioned, commencing at the top.
The time of its complete revolution is one hundred and fifty years.
[Illustration: Fig. 75.--Aspects and Revolution of Double Stars.]
The meaning of these double stars is that two or more suns revolve
about their centre of gravity, as the moon and earth about their
centre. If they have planets, as doubtless they have, the movement
is no more complicated than the planets we call satellites of Saturn
revolving about their central body, and also about the sun. Kindle
Saturn and Jupiter to a blaze, or let out their possible light, and
our system would appear a triple star in the distance. Doubtless,
in the far past, before these giant planets were cooled, it so
appeared.
We find some stars double, others triple, quadruple, octuple, and
multiple. It is an extension of the same principles that govern
our system. Some of these suns are so far asunder that they can
swing their Neptunes between them, with less perturbation than
Uranus and Neptune have in ours. Light all our planets, and there
would be a multiple star with more or less suns seen,
[Page 214]
according to the power of the instrument. Perhaps the octuple star
s in Orion differs in no respect from our system, except in the
size and distance of its separate bodies, and less cooling, either
from being younger, or from the larger bodies cooling more slowly.
Suns are of all ages. Infinite variety fills the sky. It is as
preposterous to expect that every system or world should have analogous
circumstances to ours at the present time, as to insist that every
member of a family should be of the same age, and in the same state
of development. There are worlds that have not yet reached the
conditions of habitability by men, and worlds that have passed
these conditions long since. Let them go. There are enough left,
and an infinite number in the course of preparation. Some are fine
and lasting enough to be eternal mansions.
_Colored Stars._
In the cloudy morning we get only red light, but the sun is white.
So Aldebaran and Betelguese may be girt by vapors, that only the
strong red rays can pass. Again, an iron moderately heated gives
out dull red light; becoming hotter, it emits white light. Sirius,
Regulus, Vega, and Spica may be white from greater intensity of
vibration. Procyon, Capella, and Polaris are yellow from less intensity
of vibration. Again, burn salt in a white flame, and it turns to
yellow; mix alcohol and boracic acid, ignite them, and a beautiful
green flame results; alcohol and nitrate of strontia give red flame;
alcohol and nitrate of barytes give yellow flame. So the composition
of a sun, or the special development of anyone substance thereof
at any time, may determine the color of a star.
[Page 215]
The special glory of color in the stars is seen in the marked contrasts
presented in the double and multiple stars. The larger star is
usually white, still in the intensity of heat and vibration; the
others, smaller, are somewhat cooled off, and hence present colors
lower down the scale of vibration, as green, yellow, orange, and
even red.
That stars should change color is most natural. Many causes would
produce this effect. The ancients said Sirius was red. It is now
white. The change that would most naturally follow mere age and
cooling would be from white, through various colors, to red. We are
charmed with the variegated flowers of our gardens of earth, but
he who makes the fields blush with flowers under the warm kisses of
the sun has planted his wider gardens of space with colored stars.
"The rainbow flowers of the footstool, and the starry flowers of
the throne," proclaim one being as the author of them all.
_Clusters of Stars._
From double and multiple we naturally come to groups and clusters.
Allusion has been made to the Hyades, Pleiades, etc. Everyone has
noticed the Milky Way. It seems like two irregular streams of compacted
stars. It is not supposed that they are necessarily nearer together
than the stars in the sparse regions about the pole. But the 18,000,000
suns belonging to our system are arranged within a space represented
by a flattened disk. If one hundred lights, three inches apart,
are arranged on a hoop ten feet in diameter, they would be in a
circle. Add a thousand or two more the same distance apart, filling
up the centre, and [Page 216] extending a few inches on each side of
the inner plane of the hoop: an eye in the centre, looking out
toward the edge, would see a milky way of lights; looking out toward
the sides or poles, would see comparatively few. It would seem as if
this oblate spheroidal arrangement was the result of a revolution of
all the suns composing the system. Jupiter and earth are flattened
at the poles for the same reason.
[Illustration: Fig. 76.--Sprayed Cluster below ae in Hercules.]
[Illustration: Fig. 77.--Globular Cluster.]
In various parts of the heavens there are small globular well-defined
clusters, and clusters very irregular in form, marked with sprays
of stars. There is a cluster of this latter class in Hercules,
just under the S, in Fig. 72. "Probably no one ever saw it with a
good telescope without a shout of wonder." Here is a cluster of the
former class represented in Fig. 77. "The noble globular cluster,
o Centauri is beyond all comparison the richest and largest object
of the kind in the heavens. Its stars are literally innumerable;
and as their total light, when received by the naked eye, affects
it hardly more than a star of the fifth to fourth
[Page 217]
magnitude, the minuteness of each star may be imagined."
There are two possibilities of thought concerning these clusters.
Either that they belong to our stellar system, and hence the stars
must be small and young, or they are another universe of millions
of suns, so far way that the inconceivable distances between the
stars are shrunken to a hand's-breadth, and their unbearable splendor
of innumerable suns can only make a gray haze at the distance at
which we behold them. The latter is the older and grander thought;
the former the newer and better substantiated.
_Nebulæ._
The gorgeous clusters we have been considering appear to the eye
or the small telescope as little cloudlets of hazy light. One after
another were resolved into stars; and the natural conclusion was,
that all would yield and reveal themselves to be clustered suns,
when we had telescopes of sufficient power. But the spectroscope,
seeing not merely form but substance also, shows that some of them
are not stars in any sense, but masses of glowing gas. Two of these
nebulæ are visible to the naked eye: one in Andromeda (see Fig.
68), and one around the middle star of the sword of Orion, shown
in Fig.78. A three-inch telescope resolves th Orionis into the
famous trapezium, and a nine-inch instrument sees two stars more.
The shape of the nebula is changeable, and is hardly suggestive of
the moulding influence of gravitation. It is probably composed of
glowing nitrogen and hydrogen gases. Nebulæ are of all conceivable
shapes--circular, annular, oval, lenticular, [Page 218] conical,
spiral, snake-like, looped, and nameless. Compare the sprays of the
Crab nebulæ above z Tauri, seen in Fig. 79, and the ring nebula,
Fig. 80. This last possibly consists of stars, and is situated, as
shown in Fig. 81, midway between b and g Lyræ.
[Illustration: Fig. 78.--The great Nebula about the multiple Star
th Orionis. (See Frontispiece.)]
When Herschel was sweeping the heavens with his telescope, and
saw but few stars, he often said to his assistant, "Prepare to
write; the nebulæ are coming." They are most abundant where the
stars are least so. A zone about the heavens 30° wide, with the
Milky Way in the centre, would include one-fourth of the celestial
sphere; but instead of one-fourth, we find nine-tenths
[Page 219]
of the stars in this zone, and but one-tenth of the nebulæ.
These immense masses of unorganized matter are noticed to change
their forms, vary their light greatly, but not quickly; they change
through the ages. "God works slowly." He takes a thousand years
to lift his hand off.
[Illustration: Fig. 79.--Crab Nebula, near z Tauri. (See Frontispiece.)]
There are many unsolved problems connected with these strange bodies.
Whether they belong to our system, or are beyond it, is not settled;
the weight of evidence leans to the first view.
[Page 220]
_Variable Stars._
[Illustration: Fig. 80.--The Ring Nebula.]
Our sun gives a variable amount of light, changing through a period
of eleven years. Probably every star, if examined by methods
sufficiently delicate and exact, would be found to be variable.
The variations of some [Page 221] stars are so marked as to
challenge investigation. b Lyræ (Fig. 81) has two maxima and minima
of light. In three days it rises from magnitude 4-1/2 to 3-1/2; in a
week falls to 4, and rises to 3-1/2; and in three days more drops to
4-1/2: it makes all these changes in thirteen days; but this period
is constantly increasing. The variations of one hundred and
forty-three stars have been well ascertained.
[Illustration: Fig. 81.--Constellation Lyra, showing place of the
Ring Nebula.]
Mira, or the Wonderful, in the Whale (Fig. 68), is easily found when
visible. Align from Capella to the Pleiades, and as much farther,
and four stars will be seen, situated thus:
*
* * *
The right-hand one is Mira. For half a month it shines as a star
of the second magnitude. Then for three months it fades away, and
lost to sight; going down even to the eleventh magnitude. But after
five months its resurrection morning mes; and in three months
more--eleven months in all--our Wonderful is in its full glory
in the heavens. It its period and brilliancy are also variable.
The star Megrez, d in the Great Bear, has been growing dim [Page
222] for a century. In 1836 Betelguese was exceedingly variable, and
continued so till 1840, when the changes became much less
conspicuous. Algol (Fig. 68) has been already referred to. This
slowly winking eye is of the second magnitude during 2d. 14h. Then
it dozes off toward sleep for 4h. 24m., when it is nearly invisible.
It wakes up during the same time; so that its period from maximum
brilliancy to the same state again is 2d. 20h. 48m. Its recognizable
changes are within five or six hours. As I write, March 25th, 1879,
Algol gives its minimum light at 9h. 36m. P.M. It passes fifteen
minima in 43d. 13m. There will therefore be another minimum May 7th,
at 9h. 49m. Its future periods are easy to estimate. Perhaps it has
some dark body revolving about it at frightful speed, in a period of
less than three days. The period of its variability is growing
shorter at an increasing rate. If its variability is caused by a
dark body revolving about it, the orbit of that body is contracting,
and the huge satellite will soon, as celestial periods are reckoned,
commence to graze the surface of the sun itself, rebound again and
again, and at length plunge itself into the central fire. Such an
event would evolve heat enough to make Algol flame up into a star of
the first magnitude, and perhaps out-blaze Sirius or Capella in our
winter sky.
None of the causes for these changes we have been able to conjecture
seem very satisfactory. The stars may have opaque planets revolving
about them, shutting off their light; they may rotate, and have
unequally illuminated sides; they may revolve in very elliptical
orbits, so as to greatly alter their distance from us; they may
be so situated in regard to zones of meteorites as [Page 223] to
call down periodically vast showers; but none or all of these
suppositions apply to all cases, if they do to any.
_Temporary, New, and Lost Stars._
Besides regular movements to right and left, up and down, to and
from us--changes in the intensity of illumination by changes of
distance--besides variations occurring at regular and ascertainable
intervals, there are stars called _temporary_, shining awhile and
then disappearing; _new_, coming to a definite brightness, and so
remaining; and _lost_, those whose first appearance was not observed,
but which have utterly disappeared.
In November, 1572, a new star blazed out in Cassiopeia. Its place
is shown in Fig. 67, ch g being the stars
d *
g ch
in the seat of the chair, and d being the first one in the back.
This star was visible at noonday, and was brighter than any other
star in the heavens. In January, 1573, it was less bright than
Jupiter; in April it was below the second magnitude, and the last
of May it utterly disappeared. It was as variable in color as in
brilliancy. During its first two months, the period of greatest
brightness, it was dazzling white, then became yellow, and finally
as red as Mars or Aldebaran, and so expired.
A bright star was seen very near to the place of the _Pilgrim_,
as the star of 1572 was called, in A.D. 945 and 1264. A star of
the tenth magnitude is now seen brightening slowly almost exactly
in the same place. It is possible that this is a variable star
of a period of about three hundred and ten years, and will blaze
out again about 1885.
But we have had, within a few years, fine opportunities [Page 224]
to study, with improved instruments, two new stars; On the evening
of May 12th, 1866, a star of the second magnitude was observed in
the Northern Crown, where no star above the fifth magnitude had been
twenty-four hours before. In Argelander's chart a star of the tenth
magnitude occupies the place. May 13th it had declined to the third
magnitude, May 16th to the fourth, May 17th to the fifth, May 19th
to the seventh, May 31st to the ninth, and has since diminished to
the tenth. The spectroscope showed it to be a star in the usual
condition; but through the usual colored spectrum, crossed with
bright lines, shone four bright lines, two of which indicated
glowing hydrogen. Here was plenty of proof that an unusual amount of
this gas had given this sun its sudden flame. As the hydrogen burned
out the star grew dim.
Two theories immediately presented themselves: First, that vast
volumes had been liberated from within the orb by some sudden breaking
up of the doors of its great deeps; or, second, this star had
precipitated upon itself, by attraction, some other sun or planet,
the force of whose impact had been changed into heat.
Though we see the liberated hydrogen of our sun burst up with sudden
flame, it can hardly be supposed that enough could be liberated
at once to increase the light and heat one hundred-fold.
In regard to the second theory, it is capable of proof that two
suns half as large as ours, moving at a velocity of four hundred
and seventy-six miles per second, would evolve heat enough to supply
the radiation of our sun for fifty million years. How could it be
possible for a sun like this newly blazing orb to cool off to such a
[Page 225] degree in a month? Besides, there would not be one chance
in a thousand for two orbs to come directly together. They would
revolve about each other till a kind of grazing contact of grinding
worlds would slowly kindle the ultimate heat.
It is far more likely that this star encountered an enormous stream
of meteoric bodies, or perhaps absorbed a whole comet, that laid
its million leagues of tail as fuel on the central fire. Only let
it be remembered that the fuel is far more force than substance.
Allusion has already been made to the sudden brightening of our
sun on the first day of September, 1859. That was caused, no doubt,
by the fall of large meteors, following in the train of the comet
of 1843, or some other comet. What the effect would have been, had
the whole mass of the comet been absorbed, cannot be imagined.
Another new star lately appeared in Cygnus, near the famous star
61--the first star in the northern hemisphere whose distance was
determined. It was first seen November 24th, 1876, as a third magnitude
star of a yellow color. By December 2d it had sunk to the fourth
magnitude, and changed to a greenish color. It had then three bright
hydrogen lines, the strong double sodium line, and others, which
made, it strongly resemble the spectrum of the chromosphere of our
sun. An entirely different result appeared in the fading of these
two stars. In the case of the star in the Crown, the extraordinary
light was the first to fade, leaving the usual stellar spectrum. In
the case of the star in Cygnus, the part of the spectrum belonging
to stellar light was the first to fade, leaving the bright lines;
that is, the gas of one gave way to regular starlight, and the
starlight [Page 226] of the other having faded, the regular light of
the glowing gas continued. By some strange oversight, no one studied
the star again for six months. In September and November, 1877, the
light of this star was found to be blue, and not to be starlight at
all. It had no rainbow spectrum, only one kind of rays, and hence
only one color. Its sole spectroscopic line is believed to be that
of glowing nitrogen gas. We have then, probably, in the star of
1876, a body shining by a feeble and undiscernible light, surrounded
by a discernible immensity of light of nitrogen gas. This is its
usual condition; but if a flight of meteors should raise the heat of
the central body so as to outshine the nebulous envelope, we should
have the conditions we discovered in November, 1876. But a rapid
cooling dissipates the observable light of all colors, and leaves
only the glowing gas of one color.
_Movements of Stars._
We call the stars _fixed_, but motion and life are necessary to all
things. Besides the motion in the line of sight described already,
there is motion in every other conceivable direction. We knew Sirius
moved before we had found the cause. We know that our sun moves
back and forth in his easy bed one-half his vast diameter, as the
larger planets combine their influence on one side or the other.
The sun has another movement. We find the stars in Hercules gradually
spreading from each other. Hercules's brawny limbs grow brawnier
every century. There can be but one cause: we are approaching that
quarter of the heavens. (See [Symbol], Fig. 72.) We are even [Page
227] able to compute the velocity of our approach; it is four miles
a second. The stars in the opposite quarter of the heavens in Argo
are drawing nearer together.
This movement would have no effect on the apparent place of the
stars at either pole, if they were all equally distant; but it
must greatly extend or contract the apparent space between them,
since they are situated at various distances.
Independent of this, the stars themselves are all in motion, but so
vast is the distance from which we observe them that it has taken
an accumulation of centuries before they could be made measurable.
A train going forty miles an hour, seen from a distance of two
miles, almost seems to stand still. Arcturus moves through space
three times as fast as the earth, but it takes a century to appear
to move the eighth part of the diameter of the moon. There is a
star in the Hunting Dogs, known as 1830 Groombridge, which has a
velocity beyond what all the attraction of the matter of the known
universe could give it. By the year 9000 it may be in Berenice's
Hair.
Some stars have a common movement, being evidently related together.
A large proportion of the brighter stars between Aldebaran and
the Pleiades have a common motion eastward of about ten seconds
a century. All the angles marked by a, b, g, ch Orionis will be
altered in different directions; l is moving toward g. l and e
will appear as a double star. In A.D. 50,000 Procyon will be nearer
ch Orionis than Rigel now is, and Sirius will be in line with a and
ch Orionis. All the stars of the Great Dipper, except Benetnasch
and Dubhe, have a common motion somewhat in the direction [Page 228]
of Thuban (Fig. 67), while the two named have a motion nearly
opposite. In 36,000 years the end of the Dipper will have fallen out
so that it will hold no water, and the handle will be broken square
off at Mizar. "The Southern Cross," says Humboldt, "will not always
keep its characteristic form, for its four stars travel in different
directions with unequal velocities. At the present time it is not
known how many myriads of years must elapse before its entire
dislocation."
These movements are not in fortuitous or chaotic ways, but are
doubtless in accordance with some perfect plan. We have climbed
up from revolving earth and moon to revolving planets and sun,
in order to understand how two or ten suns can revolve about a
common centre. Let us now leap to the grander idea that all the
innumerable stars of a winter night not only loan, but must revolve
about some centre of gravity. Men have been looking for a central
sun of suns, and have not found it. None is needed. Two suns can
balance about a point; all suns can swing about a common centre.
That one unmoving centre may be that city more gorgeous than Eastern
imagination ever conceived, whose pavement is transparent gold,
whose walls are precious stones, whose light is life, and where
no dark planetary bodies ever cast shadows. There reigns the King
and Lord of all, and ranged about are the far-off provinces of his
material systems. They all move in his sight, and receive power
from a mind that never wearies.
[Page 229]
XI.