Omaha daily bee. (Omaha [Neb.]) 187?-1922, 1915-12-06

astrolo gi ally ~
minded persons
with mysterious awe.
II you will imagine this earth 20 be n
huge spherical top. spinning daily upon
a peg which is tipped about % degrees
from the vertical. and also, like any other
top. turning slowly round upon the point
of Its peg so that the upper end Of tho
peg describes a circle In the air. you
will have the first conception necessary
for understanding the procession OF the
equinoxes.
Let the earth's axis be the peg: let
she north pole be the upper end OF the
peg, let The circle OF the ecliptic which
the sun appears to describe once a year
around the earth, be parallel to the in
visible floor on which the top is sup
posed TO be spinning. and just 30 high
above that floor that It's plane cuts
through the center OF the earth-top.
Then. back Of all. among the stars.
which surround the scene like the
spangled walls OF a circular room. let
there be band sixteen degrees In width.
extending completely around. with the
plane Of the ecllptc marking It's CEN
trail line. This starry band will be the
Kodiac Divide Il into twelve equal parts,
each thirty degrees long, and they will
be the "sisns" of zodiac.
Now. remember that the top Is spin
ming from its peg. or axis. inclined from
the perpendicular. II the peg stood up
right the central line OF the zodiac, or
ecleptic, would lie In the plane OF the
tops equator, ard the sun. travelling
around the circle Of the ecliptic. would
always be directly over the equator. As
things really are. however. the tippingl
OF the peg. or axis. causes the sun 70
appear above the equator during one
half Of It's revolution. or one-half OF the
year, and below II during the other half
The minute inhabitants OF the spin
ming top. being very intellectual crea-
lures, understand that this apparent up
and down swing OF the sun. In tho course
Of every year. il due to the inclination
OF the equator OF their top to the circle
of the ecliptic and In order TO make a
graphical explanation Of the phenomenon
they project the plane Of the equator In
the form Of an imaginary circle against
the starry background OF the heavens,
and they find that this circle cuts the
circle OF the ecliptic at two opposite
points on the band OF the Eodiac.
At one OF these points the sun is seen
rising above the eovator at the beginning
OF It's half-yearly course on the upper
side OF the equator (the summer half OF
the year for the northern hemisphere)
and at the opposite point the sun is seen
descending below the equator for the
winter half.
The first point Is the most important.
since Il denotes the beginning of the year.
OF the opening OF the spring season. for
the inhabitants OF the upper hemisphere.
and It IL called the spring. or vernai
equinox. When the zodiac was invented.
its first sign. Aries. was made to begin
at this point. 80 that the sun enters
Aries at the moment It rises to the
level OF the equator at the beginning OF
spring.
Then. travelling eastward. It passes in
Succession through the other signs-Tau-
rus. Gemini. Cancer. Leo. Virgo. IAbra.
Soorpio. Sagittarus. Capricornus. Aquarius
and Pisces-and. having thus completed
the circle Of the zodiac. comes back again |
10 the spring equinox. At the beginning |
OF Libra Il passess below the equator
Now. here Is an important thing to |
remember: In the beginning the signs |
OF the zodiac were visibly indicated in |
the sky by groups OF stars called con- |
steilations. and these zodiacal c0nstella- |
tions. not only bore the same names as
the signs. but occupied precisely the same |
spaces in the ring OF the zodiac.
This state Of things would have con-
tinued forever but for that slow. swing |
i-g round OF the peg OF the earth-top 10 |
which reference has been made. The re- |
suit of this motion. which gradually |
changes the direction OF the peg. or axis. |
Is TO cause the points where the sun |
crosses the equator 70 move. or slide, |
round the xodiacai ring. In a western |
direction. 80 that the signs Of the zodiac. |
which continue to be counted from the |
spring equinoctiai point. are slowly buck |
ing around the circle and fall out OF ac-
cord with the corresponding eonstella- |
tons which retain their places on the |
background OF the sky.
AZ the present time this motion. which |
Il the procession Of the equinoxes. has
brought the sign Aries back into the con-
fteIlation Pisces, 50 that. az the beginning |
Of the spring. the sun comes up above the |
EQUATOR among the stars Of Pisces instead !
Of among those OF Aries. as Il did about
2,loo years ago.
The entire time required for one COM
Ilete swing OF the axis OF the earth IL
sbout $500 years. Al the end OF that
period the signs and the consultations Of
tho zodiac must come round again into
coincidence. the signs having backed
Through the entire circle.
This imposing phenomenon was discov-
cred In the days Of the Greek astronomer
Bipparchus. but SIS cause was not found
out until Newton had unrayelied the law
~ sravitati0n. Then IL was seen that the
attraction Of the sun and moon on the
equatorial protuberanee OF the earth
caused the latter 20 behave exactly like
q spinning top whose peg Is tipped out
q the perpendicular. and which, instead
a taking swings round and round. but
with motion much slower than that OF
tie spin.
A % any relation between the process |
sion Of the equlnQEes and the phases OF
relisiops belief, / must leave that 10 those
Who can show = reason for Il.