South Bend news-times. (South Bend, Ind.) 1913-1938, 1920-08-29
THE HEA VEINS IN SEPTEMBER
By DR.. c. S. BRAININ
Of Columbia University Observatory staff.

September IS one OF the months in
which the sun claims a share OF our
attention, for IL will cross the eoua-
tor in It's southwark journey, prepar-
ing us for the coming Of winter. The
exact time OF this phenomenon by
Eastern standard time will be $40
a. m. on the morning OF the 23d.
The point on the equator which the
sun occupies at this moment is
known 10 astronomers as the au-
tumnal equinox, for on that date the
sun Is above the horizon as long as
IL is below or, in other words. day
and night are equally long.
OF course. this Is slightly modified
by the results Of atmospheric refrac-
ticn and reflection, and the day gains
somewhat at the expense Of the
night The former causes the sun
TO appear slightly higher In the sky
than IL really is. when near the hori-
zon; the latter produces the twilight
period. which Is caused by the refiec-
ton OF sunlight TO us from the up
per layers Of atmosphere after the
sun has already been seen TO dip
below the horizon.
We have a word TO say about our
friend. the moon. also. II you note
me nth when IL Is about full. you viii
I'D that the time Ct moonrise on
several consecutive nights is very
closely the same. The moon rises
about the time OF sunset, and re-
mains above the horizon until the
sun IS ready TO come once more. The
full moon nearest the time Of the
suns arrival at the autumnal equi-
nox has this desirable property sew
eral nights in succession and is
called the Harvest Moon, because its
light aids the farmer to harvest his
crops, which in certain localities are
ready for harvesting just ct this
time.
On the average, the moon rises
about an hour later each day. for Il
has to mike the complete round Of
the heavens each month It's orbit
in the sky is very close 10 the ecliptic
and may be considered practically
identical with II for rough approx
nations. II so happens that the
ecliptic's orientation In the heavens
gives this minimum retardation Of
rising when a body moving IN the
ecliptic Is near the vernal. or spring,
equinox. OF course. the moon is at
this point once each month and so
has a minimum OF daily retardation
OF rise each month, but this can
only be at full-moon time, when the
sun is in the opposite part of the
ecliptic or at the autumnal equinox.
That is why the full moon at this
time has such an appropriate name.
The next following full moon also
is sometimes given a special name
the Hunters Moon.
The Planets.
Our monthly map shows only two
planets. the all-but-visible Uranus
and ruddy Mars, far down on the
/ western horizon, ready to disappear
/ from our map for many months.
/ Mars can be better observed before
| the close of the brighter twilight pc
riod in the southwestern quarter Of
| the sky. Mars IS rapidly moving
! eastward through the field OF stars.
Those who have been following the
motion will recall that only a few
months ago Mars was close neigh
Dor OF the fixed star SDica' in Virgo.
! Venus is also an evening star, be-
| ing visible for a short time after sun
set. and. unlike Mars, its position is
gradually improving. Jupiter is a
morning star again, while Saturn
and Mercury are too near the sun
for any observation at all.
The Stars.
There are seven first-magnitude
stars shown on the map. In the
west and southwest are Arcturus and
Antares, respectively; almost over
head is the great triangle OF Vega.
Deneb and Affair; in the far North
east and in the southeast ere two
newcomers. Capella. IL Auriga, and
Fomalhaut. the brightest star in the
Southern Fish.
L..
teresting object II is the nearest TO
the North Pole OF all the first-mag
nitude stars about a degree nearer
than Deneb. II is a white star, per-
haps slightly yellowish, only a little
less brilliant than Vega of Lyra. The
sDectrum OF this star is very much
like that OF the sun, so that il must
resemble the latter IN physical char
acteristics, but, as we know its dis
lance from us TO be not less than
thirty-six hght-years. IL must be at
least 200 times as great a radiator
Of light and heat as the sun. In
fact. if the sun were suddenly re-
moved 10 a distance as great as Ca
pella's. its tremendous brilliancy
would shrink 70 the insignificance Of
a NTH magnitude star. just above
the lower limit OF visibility.
Capella is known TO be moving
away from the solar system with
speed of about twenty miles per sec
ond. Il is in reality not one star
at all, for the spectroscope has
shown that what we call Capella is
really a system OF two stars moving
about their common center or grav-
ity IN orbits completed in about 100
| davs. One OF the stars is about
third larger than its companion. 1t
All CArlStlan sOcistiss invited to big