Evening star., 1923-12-30
THE STARRY SKIES IN JANUARY
By Prof Barton of the University of Pennsylvania

The beautiful winter stars are with
us against Sirius. the brightest of all
at A, figure I. is nearly five times as
brilliant as Vega, the next brfShtes'
star visible here. and five and a quar-
ter times, as. bright as Cal ella, nearly
overhead at 3. Capella, however, is in
more favorable position. Other
bright stars are Rigel at c. Procyon
al d, Betegeuse at L. Adebaran at f
the twins Castor and PolluX at G and
III, Deneb at ] and Regulus at j. Only
the two planets Uranus and Neptune
invisible to the naked eye, are in the
region of the map; one near the west
ern horizon and the other near the
eastern horizon. Venus, in Capri
west in the evening twilight The
other planets are visible late in the
night, Mars in Libra, Jupiter in Scor-
pio and Saturn in Virgo.
Planets for the Year.
Now at the beginning of the year
we may state briefly what will hap
pen during the next twelve months.
Mercury will be visible in the early
evening for a few days about April
l6, August 10 and December 8, and
in the early morning about February
4, June 8 and September y. One of
the more interesting events of the
year will be the transit of Mercury
over the face of the sun, May Z. The
whole transit will not be seen from
any part of the United States, but
conditions are better in the west than
in the east. The last transit occurred
in 1914 and vas visible here, and the
next is in 1927, not visible here; then
there is one in 1910. visible in part.
Venus will be an evening star until
July 1, the morning star for the re-
maihder of the year. 1t will be far
theSt east of the sun April 81. far
thest west September 10. and bright
est May 20 and August Z. 1t Will be
conspicuous as a morning or evening
star most of the year, and the planet
will be in more favorable position for
evening observation than at any time
since 1916.
Mars approaches the earth SO close
ly this year that 1t is almost as near
as 1t can possibly come. 1t is eXcep-
tionally close at intervals of fifteen
or seventeen years, but this year 1t
is nearer than usual, even on these
occasions. Not since 1877, has 1t been
so near. 1t will be closest on August
%. Venus is the only planet whose
brightness ever exceeds that of Mars
at that time. The planet is too lar
south for the best observation from
northern observatorieS, but 1t VIII be
observed by them as we'll as possible
from both hemispheres. Mars VIII be
an evening star after August %. Ju-
piter Is Il morning star until June ,.
then evening star until December %.
Saturn is a morning star until April
10, then an evening star until Octo-
ber 2S. Uranus is an evening star
until March and after September
IL. Neptune is an evening star from
February 8 until August II. The lat
ter two planets are not visible to the
naked eye. AS all bright planets will
be visible during the spring and sum-
mer, Venus and Mars, under unus-
ually favorable conditions that part
of the year, will be an interesting one
as far as the planets are concerned.
EcIipses.
Although there are five eclipses
during the year. which is more than
the average number, no part of any
the United States There are three
partial eclipSes of the sun visible
chiefly from polar regions, as partial
eclipseS of the sun usually are, and
two total eclipses of the moon visible
from the other hemisphere. There
will be an interesting occultation of
Aldebaran on February IA. The earth
is nearest to the sun on January l.
The Calendar.
The beginning of the year is a suit
BILE time for d discussion of our cal
endar, the Gregorian calendar. In
terest In 1t Is revived by the fact that
in October it was adopted as the cal
endar of g. large number of people
who had before used a different one.
the Julian calendar. Now practically
the whole civilized world uses the
same calendar. This is the first New
Year day for all since the change. AS
Is too we'll known to require detailed
discussion here, the calendar was in
great confusion at the time of julius
Caesar and 1t became necessary that
he should take some action with re-
spect to it. He solicited the advice of
the astronomer Sosigenes and acted
upon his suggestions. Previous cal
endars had depended largely upon the
motion of the moon. Sosigenes very
wisely discarded the moon altogether
and made the calendar depend upon
the sun only. The year, as he knew,
was very nearly 365A days in length.
If S65 days was accepted as a year,
the seasons would begin about a
quarter day later each year. To pre-
vent this the scheme familiar to us
of having three consecutive years of
365 days followed by one of 366 days
1eap year, was adopted. Every
year Tin our present system of num-
bering) which Is exactly divisible by
four, was leap year. This does not
apply to b. c. dates.
This was the simple Julian calendar
used by practically the whole civil
ized world from the time of It's es-
tablishment in 45 B. c. until 1882, and
by a large but less important part of
the world until 1923. and still used
by very small part. To date ii has
been used for 1869 years.
The Gregorinn Change.
ha af he
cal year, is II IN. 14.5 s. shorter than
the 1861 days used by Sosigenes in
the Julian calendar. The difference
made the seasons occur a day earlier
than shown by the calendar in 1913
years. BY 1852 the beginning of
on March II instead of about March
"a when the Julian calendar was es-
tablished. To remedy the discrep-
ancy and prevent its recurrence.
Pope Gregory XIII called d council
for the consideration of the calendar
and upon their advice bull was is
sued changing the calendar to the
system now used by us called the
Gregorian calendar. Sections of this
papal bull are worth quotation, tran
lated, to show clearly the reasons for
the change.
considering, therefore, that three
things are required to be joined to-
gether and established for the right
C6IeD OI the leSLlVal or Easter
according to the sanctions of the holy
fathers and of the ancient Roman
Pontiffs, especially Plus and Victor
first, and also of the great Ecumen-
lcal Nicene council and of others:
First. a fixed place of the vernai
equinox; second, the correct position
of the fourteenth day of the moon
which falls either on the day of the
equinox or next follows it; lastly,
the first Sunday which follows the
same fourteenth of the moon-we
wish not only to restore the equinox
to it's former position from which IL
has receded about ten days since the
Nicene Council, and to bring back the
present moon to its place of that time
from which it is distant more than
four days, but also to provide a plan
by which hereafter the equinox and