Evening star., 1898-09-03

bright, ruddy star Antares now nearing
the horizon in the southwest Saeittarfus
Is nearly south. 1t can be recognized from
the hoppy horse il ii, described last
month, the five more easterly stars of
which form the Milk Dipper. The Eagle ia
marked by the star Affair. of the first
magnitude, which has just crossed the me-
ridian at two-thirds OF the distance from,
the horizon to the zenith The Dolphin
known also as Jobs Coffin, is the littIe
cluster of five or six small stars at the left
of Alt ur, and at about the same altitude.
The Swan (Cygnus), better known as the
Northern Cross, is directly overhead. Cas-
siopeia, strongly marked by the w-shaped
hgure formed by its five brighter stars is
| in md-hesvens in the northeast. The
triangular region between the head Of the
Cross the Pole Star and Cassiopeia is oc-
cupied by Cepheus, not a conspicuous con-
stelIation. but rich in telescopic stars The
second magnitude star midway between
Casstopeia ard the horizon is Alpha PerseI
at the center of elongated yroup of
stars which form the body of Perseus
Some ten degrees to the right of this star,
ana lower than 1t, is Beta Pcrsei, also of
the second magnitude, better known as
Algol. the Demon. This star is in the head
of Medusa. which Perseus holds by its
snaky locks in hs left hand-we speak now
L
a famous variable star.
Square of Pegasus
In midheavens in the east is the great
Square of Pegasus-a large rectangular fig
ure, formed by four stars of the second
magnitude. Only three of these stars be-
long, however, to the old constellation Pc
gasus-the Winged Horse, whose head is
row above and at The right of the square,
and " hose forefeet are paving upward to-
Uard the zenith-the star at the northeast
ern corner of the square being in the head
of Andromeda.
Between this last designated star Alpha
Andromedae and Alpha Perse on line
curElng slightly downward, are two other
stars of the same nagnit~de Both belong
to Andromeda, one of them, Reta being in
her belt, the other, Gamma, in her left
foot ADdromeda is now in her best posi-
ton for observing, reclining in that ma .ural
and easy pose which she may be imagined
to have assumed " lille bound to the rock
awaiting the arrival of the sea monster,
who, but for the timely intervention of
Perseus would have made meal of her.
Nebula of AndrOmeda.
This constellation is, however, less at
tractive to the modern stargazer for its
mythology than for its famous nebula. The
nebula lies near the northernmost of The
three stars-two Of them of only The fourth
1nagnil lude-which form dhe maiGens belt.
star, ana, indeed, 1t hau attracted alIen-
lion before The invention OF the telescope
It's nebuIous character Is quite apparent
through an opera SiaSs- Seen thu o~gn a
small Telescope ii PRESENTS appearance
which was aplIy described by Its d-scov-
erer, SIMON Marius, as that OF d candle
SHINING through hCln.
Photography las shown this intereS ing
object &c pelong 10 The class CT spiral
lepuIae. 1t is evidently turned toward as
parity edsewlse, SO tnat It's appaaent fig
ure Is euiptlcai; but the general arrange
ment Of lis numerous ''rifls' ana ''whorls''
bears unmistaka bic testimony 10 a vertical
movement going or within il. The spec
trum or th,s neoula Is somewhat perplex-
Ing To astronomers. The most OF the recog-
n-zed nebulae give spectra which consls IS
Wholly OF bright AEes-Ihree lines found IN |
the most of them are specially designated |
as The 'nebular lines and these lines i,
evidence that the light of the nebulae |
comes wholly from incandescent gaseous |
matter. The nebula in Andromeda, besides !
giving the characteristic nebular lines, |
gives also faint rainbow spectrum, which |
is interpreted TO mean that a portion of |
its light comes from matter in Tie sold or !
the liquid state.
NebuIous Theories.
OF the two gases which give the principal |
lines of this and other nebulae, cne is GER |
tainly hydrogen; the other has not as yet /
been positively identified with any ele- |
ment known to terrestrial chemistry. DR.. |
Higgins thinks it is nitrogen. while Sir i
Norman Lockyer is confident that 1t is the |
vapor of magnesium Lockyer tells u.s.
Furthermore, that these nebulae are not /
simply misses of gaseous matter at an in |
conceivably high temperature. as was the I
original conception of a nebula, but that |
they are vast clouds of mcteorites, their /
faint glow being due to the heat engen-
dered by the collisions of the meteorites |
with other-or perhaps the phenome-
non Is in part electrical-aud that the tenn |
perature of the nebula, as whole is low. |
Astrononi, rs seem gradually to be getting |
down to bottom facts In their investigation /
of these long nystifying objects, thanks /
to the spectrcscope and photography, and /
with every fresh discovery the Importance I
of the nebula in the scheme Of world evolu-
ton becomes more clearly apparent. To /
interpret the evidence-to recover the story I