THE YOUNG SCIENTIST. 
27 
Venus has passed to the west of the Sun, be- 
coming a morning star, and 34 days after her 
transit, or Jan. 9, arrives at greatest brilliancy. 
She is moving eastward past the stars of the 
constellation Scorpio, being, at the beginning of 
the month, only about 10° north of the red star, 
Antares, and on the last of the month, near the 
end of the handle of the Milk-maid's Dipper. 
Venus' phase is a large crescent. She rises on 
the 10th at 4h. 21m. a.m.; 20th, ih. 11m. a.m.; 
and 30th at 4h. 9m. a.m. 
Another Transit of Venus will not occur until 
June, 1996, 114 years hence. The present gener- 
ation of astronomers must, therefore, be content 
with the results of "the one of last December. 
Only five transits of Venus have ever occurred 
of which we have any record; they are as 
follows: December, 1639; June, 1761; June, 
1769 ; December, 1874 ; December, 1882. 
In 1629 Kepler predicted a transit which oc- 
curred in 1631, but it was not seen. He also pre- 
dicted that of 1761, but he never had the pleas- 
ure of seeing his predictions verified ; he died 
only a few days before that of 1631 occurred. 
From the transit of 1761 a solar parallax of 
8".73 was deduced, which corresponds to a dis- 
tance of 94,279,932 miles from the Earth to the 
Sun. The transit of 1874 gave, as a mean of 
several results, a parallax of 8''.82, correspond- 
ing to a distance of 83,492,526 miles. The former 
transit occurred near the time of the Earth's 
aphelion, and the latter near its perihelion. 
Allowing 3,000,000 miles as the difference be- 
tween greatest and least distances, the distance 
has been reduced by about 8,000,000 miles. The 
results of the '74 transit must be nearly correct 
(a variation in the solar parallax, when placed 
at 8".8, of 0".01 makes a difference of 104,362 
miles), and as the results of each successive 
transit depend upon the computations of the 
preceding ones, it is quite certain that the 
transit of last month will give a very close ap- 
proximation to the truth. It will bo several 
months before the final results will be known. 
3Iars was in conjunction with the sun Dec. 10, 
and is now a morning star, but will scarcely be 
seen this month, rising only one hour before 
the Sun on the 25th. His satellites will not be 
seen at all this year, even by the aid of the most 
powerful telescopes known. 
Jupiter was brightest on the 18th of last 
month, and will be the most brilliant object in 
the evening skies for many weeks. He is in the 
eastern part of the constellation Taurus, upon 
the west margin of 1 he Milky- way, and midway 
between the two stars Beta AurigsB (2d mag.) 
and ^fe^a Tauri (3d mag.), which are supposed 
to mark the tips of the Bull's horns. He is 
situated in a glorious portion of the Heavens. 
Just 30° west of him is the large V-shaped fig- 
ure in the Bull's head known as the Hyades, of 
which the splendid red double star, Aldebaran» 
is the lucida. Near by is the Pleiad group or 
"Seven-stars" (a misnomer, as 12 stars have 
been seen in this group, and charted, with the 
unassisted eye, and 499 have been charted, down 
to the 14th magnitude). Capella and the beau- 
tiful little triangle called the "Kids" are north, 
and Betelguesc about the same distance south 
of hitn. Orion with its grand array of magnifi- 
cent objects, is below or soutli of Jupiter, and 
Procyon and Gemini east of him. 
The celebrated "Crab Nebula" is about 1° 
south of him on the 26th, which position will be 
practically retained for several days before and 
after that date. This will be a good time to- 
look for that interesting object which may be 
seen with small telescopes. This is the Nebula, 
which the Earl of Kosse resolved into stars with 
his 6-feet reflector. It looks more like a vast 
pineapple than a crab, however, with its 
branches clustering with gems and gold. 
JUPITER'S SATELLITES. 
The following are the eclipses of Jupiter's 
Moons which are visible at seasonable hours: 
D. H. M. 
Satellite II. 1 7 16 even'g.— Keappearance. 
I. 2 11 0 " ' " 
" III. 4 6 48 
II. 8 9 52 
I. 11 7 24 
" III. 11 10 50 
I. 18 9 19 
Jupiter's shadow is now projected west of 
him, but so slightly that the satellites pass 
from occupations into eclipses without becom- 
ing visible, hence the beginning of the eclipses 
and end of the occultations cannot be seen, trans- 
piring, as they do, behind the planet, and the 
satellites suddenly become visible some little 
distance west or to the right of the planet. 
The early-evening occultations begin as fol- 
lows : 
Occultations. Transits. 
Sat. D. H. M. Sat. D. H. M. 
I. 2 8 22 I. 3 5 41 ingress. } 
II. 8 6 5 I. 3 7 56 egress. S 
I. 9 10 7 I. 10 7 25 ingress. > 
III. 11 5 44 I. 10 10 16 egress. \ 
II. 15 8 21 II. 24 7 41 egress. 
I. 18 6 19 I. 26 7 40 egress. 
II. 22 10 40 II. 31 7 19 ingress. ]; 
I. 25 8 7 II. 31 10 4 egress. S 
The transits occurring when the satellites are 
in the nearer portions of their orbits must occur 
from left to right, and the shadows follow the 
satellites ; the shadow of I. beginning its transit 
22m., II. 50m.. and III. Ih. 54m. after the respec- 
tive satellites begin theirs. Jupiter passes the 
