Evening star., 1925-03-01
;TARRY SKIES IN MARCH
By Prof Samuel G. Barton the University Pennsy

There is little of an unusual character
expected to happen this month. Mer-
| curry is at its greatest eastern elonga-
| tion on March 80. This means that II
is farther east of the sur than before or
after that time. This planet is usually
so near the sun that 1t cannot be seen
because 1t Is blotted out by the brilliant
sunlight The position of Mercury
| among the stars on March 80 Is shown
| in figure l. This map, however. is made
for the list of the month, at o'clock.
1t represents the sky at o'clock on
March 80, SO, of course 1t will be neces-
sary to look for Mercury even earlier
| than that in order to have 1t far enough
above the horizon. II can be seen in the
| twilight, and must be seen then. 1t is
of zero magnitude, which indicates that
| 1t is brighter than any object in the sky
except the moon and the star Sirius, at
A This viii be the most favorable op-
portunity for seeing the planet this year
in the evening. but other years afford
more favorable opportunities. Mercury
! changes its position rapidly. so that 1t
will be near the position indicated for
only a few days.
The position of Mars on the first and
last days of the month is marked on
figure l. This planet is not conspicuous
now. 1t is fainter than several of the
stars. The stars Sirius at A.. Capella at
B, Rigel at c, Procyon at D, Betelgeuse
at E, Aldebaran at F.. Pollux at and
Arcturus at H are brighter than Mars
at the first of the month, and by the end
of the month Regulus at J and Castor at
K may be added. for Mars is steadily
growing fainter as its distance from
the earth increases.
The only other planet whose position
can be shown on the map is Neptune,
which is not visible to the naked eye.
Venus and Uranus are too close to the
sun to be seen. Jupiter. in Sagittarius,
and Saturn, in Libra, may be seen late in
the night This is the proper time Of
the year to look for the zodiacal light,
the beam of light which may be seen ex-
tending along the eclfptic upward from
the western horizon. During the month
the moon passes very close to the star
Aldebaran at A twice. March and
March 20. and close to Neptune and
Regulas on March g. and from some
places these stars will be seen to be oc-
Quilted.
Baade's Asterotd.
The press of other matter has here
fofore prevented a discussion of rather
remarkable object found last October.
On October 23 last the astronomer
Baade. at the great observatory at Ber-
gedorf, Germany. discovered a new OBJ
ject, which from the first gave indica-
ton of being an unusual object, because
of its rapid motion. There are but two
kinds of objects which move with suf-
ficient rapidity to make a change of DO
sition noticeable in few hours namely,
planets or comets. excluding new satel-
lttes which would be found only near
known planets. The object looked like
a star; comets ordinarily do not. In
any case, the rapid motion, about a de-
gree and half per day, indicated that
the object must be comparatively near
the earth. There has been no discovery
of major planet since Neptune was
discovered in 1846, but discoveries of
minor planets. commonly called aste-
rotds, are OF frequent occurrence. These
asteroids are very small planets which
revolve about the sun like the other
planets, but are not scattered like those
OF larger size. Nearly all-about 900
are known-have orbits between those
OF Mars and Jupiter. Discoveries of
ne" asteroids are much more frequent
than discoveries of comets. The discoy-
cry or a new asteroid receives very little
attention unless the asterofd is peculiar
IN some respect This new object had
an unusually, but not impossibly, rapid
motion FOR an asteroid, SO its true ma
ture was in some doubt until the orbit
was computed
IN order TO determine the path in
which the object was moving 1t was
necessary to note-its position accurately
at three times, separated by at least a
few days. with a record of the times a .
well. The observations used for the
preliminary determination of the orbit
were made on October 27, October 80
and November 3. This orbit showed def
initely that the object was an interesting
asteroid. AS indicated by the rapid mo-
ton, the asteroid was relatively near
the earth at the time. of discovery. At
this time 1t was about half as far from
US as the sun, or about 46. 1000, 900 miles.
1t was closer then than Mars. The aste-
roid, however. was closest to the earth
early In September. when 1t was a little
over third as far from .us as the sun.
or about the same distance as Mars at
the time when We were so excited about
the nearness of that planet When dis.