The sun., 1882-06-18
,vE EtR7H'S TBIN SISTER.

ryerybody must have noticed the brilliant
-,ar,hn, chimes in the west just after sundown.
Imnylrforc any other stars are visible in the
t,yilirlt. /. sparklos like u diamond against the
,ost rlnw " the sunset; and as the heavens
,orkcu Il grows brighter and brighter, making
avon Arrturus and Cnpclla look dim by con-
,r,st with IT, splcndor, and attracting the eye
ulc n signal lamp. Night by night 1t rises
higbcr and glows yet moro brilliantly. Those
who watch it through tho coming summer
awnings will SEQ IL increase until like n min
i,turc sun It casts shadows behind the objects
upon which it Shines This splendid twinklcr
Is tho planet Venus and it deserves the name
a, the irwin Sister OF the Earth
There are indeed many points of resemblance
be,wcon the globo we tread and that beautiful
star, They are both Of nearly the same size
Venus being only about 800 miles smaller
In diameter than tho earth. The sea-
sons on Venus are believed to be very like
our seasons since her inclination to
tho plane Of her orbit resembles that of
the earth. Tho day on Venus. according to
tho hest estimates Of the period OF her rotation.
ia only about half an hour shorter than our
day The weight of bodies on Venus is nearly
the same rs on the earth. Her yoar is only
about 22j days long instead OF 365, and being
nearer the sun, she gets considerably more
light and heat than We do. She has an atmos-
phere more extensive than ours. which Is visi-
BILE at times a ring Of light around the edge
Of the planet. Certain spectroscopic observa-
tons.have led to the inference that her atmos-
pherc resembles ours In its composition. II
she has an atmosphere like ours. she undoubt-
edy has oceans and rivers and clouds. and
with them animal and vegetable life. In fact.
thero is some reason to think from the tele-
scopic appearance Of Venus and her excessive
brightness. that her atmosphere is more
cloudy than ours. for the upper surfaces OF
clouds reflect light rs brilliantly as snow. IL
this is 80. the clouds may serve to protect the
planets surface from the intensity OF the suns
rays. Mr.. Proctor says OF the similarity be-
tween Venus and the earth: " Had Venus but
moon as the earth has. we might doubt
whether in the whole universe two orbs exist
which are SO strikingly similar to each other"
The question OF Venus's moon Is one OF the
most interesting and puzzling in astronomy.
The evidence that Venus has moon Is very Gu
rious. Some astronomers pretend to have seen
yenus's moon; others deny the possibility Of
Its existence. not on the ground that there is
any physical reason against it, but because the
best modern telescopes have never revealed
its presence. Mr. Proctor, after reviewing the
evidence. Is inclined to put Venus's moon in
the category Of astronomical illusions. But
then astronomers used to talk eonflds ntly OF
the snowy poles OF moonless Mars" and
now we know that Mars has two
moons. Moreover. these moons have since
their discovery been seen with many tele-
scopes which never showed them before. 80
that the mere fact that big telescopes have not
shown Nenus's moon is not conclusive evil
dence that it does not exist. Most Of the al
legged observations of Venus g moon were made
in the last century. when telescopes had not
reached the perfection which they have since
attained: yet too much stress cannot be
laid upon that fact for modern as
tronomcrs frequently have occasion to
express surprise at the kocn powers of
observation shown by the star gazers
OF ono or two hundred years ago. An example
OF this was the observation by David Ritten-
house OF Philadelphia in 1869 of the circle of
light which the refractive power of Nenuss
atmosphere throws around the planet when il
Is between the earth and the sun. The same
phenomenon was not noticed again until 1866.
and there are very few recorded observations
Off in modern times. Yet nobody regards II
rs a deceptive appearance. Besides. it must
be remembered that the large telescopes in the
observatories are not very often employed in
such searches. Professional astronomers.
especially those who draw salaries from
that Venus has no moon. and II would
do no good to their self-complacency to have
one discovered. Amateurs may do better. The
last reported observation of Venus's moon that
we recollect was made by a Pennsylvania anna
teur astronomer named S;nytn in April, 1873.
The earlier oesSrvAtiOns were made by such
men -, Cassini and Short. who were among the
most famous astronomers Of their time. Upon
the whole il may be said that while the exist
encc Of Venus's moon has not been established
1t has also not been disproved. and every such
opportunity as the present, when Venus swings
into the ncighborhood of the earth. should be
employed in the search for it. 1t is noteworthy
that one Of the observations Of tho supposed
moon was made during the transit of the
planet across tho suns disk in l76l. No
similar observation has since been made, but
dur!n. tho transit of next December an oppor
tunity will be offered to test the matter again.
1t is curious fact that all the earliest observa-
tons Of Nenus's moon We're made between
1872 and 1856. 1t was again seen between $40
and l764 After that II seems not TO have been
detected until the Pennsylvania observer.
Smyth reported that he had seen il in 1878.
Something like II century intervenes between
each set Of observations and tho follow
ing set. 1t was during what, Tor the
sake OF convenience. we may call the second
period Of visibility that it was seen: ac-
cnrding to Schcuten. in transit with Venus
across the sun. II it really was detected in
1878 then there is tho more hope Of its being
seen again during tho transit in December,
since this transit. like that Of lI6l. falls III one
Of the supposed periods Of visibility. 1t is al
most Impossible. however. to imagine any suf-
G"cut reason why. ii such n body exists, it
should only be- visible for "A few years ut n time,
and t.on disappear for upward OF century.
The great briiiiancy Of Venus renders ii cN-
cH"d.usly dihicult to study her appearance with
tun telescope. Some skilful observers have
drawn maps NJ the spots seen upon her sur
iar': some have s"cn. or thought they saw,
mouLtpius Others equally skiliul have denied
TIM any spots arc visible. Their visibility
s,unS lu depend upon the state OF the air, and
tA'y Ift,c been best seen in tn" sky Of italy,
TI. most interesting result that could be OBJ
RirnI by the study of Venus would be the an
sw"r ~ TIA" question. Is the planet inhabited ;
~ present astronomers appear to be pretty
una. u4vES ~ t;rc 0Tirion rr;' II any ono Of the
sun 'dW.ly of worlds besides the earth is in
MHhllo Venus is most likely to be that one.
Ibl faith Of those who bel lieve in the doctri@.
Of ~" plurality # worlds having hcen driven
llom ihr aire-s and waterlcSs orb Of the an
rnu' moon md repealed from the fiery furnace
o' ~. sun. from the deserts Of Mars and the
tumh.iDg yapors Of Jupiter and saturn. and
b'lhE luHbi' 10 penetrate the mysteries Of far
away Uranus and Neptune, may yet rest upon
venus. Ih"r" there il the same round Of SEA-
hHl- A',l tlp glIprlGt ions of Iuy and night