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Stars
In Egypt and Mesopotamia over five thousand years ago, most present
constellations had their origin. There were no books showing the stars ---
probably parents drew in the sand with a stick, then went out at night and
studied the sky. A plain Chaldean shepherd, thousands of years ago,
probably knew the sky better than the majority of college graduates today.
If you want to know the stars, you must go out and look at the sky. Pick
a spot where street lights, houses, and trees don't obstruct your view too
much. On clear moonless nights you will see the most, because light from
the moon blots out faint stars. But as those nights are rare, don't wait
for them. Even with moonlight and a few clouds, you can see many stars.
EQUIPMENT:
Your eyes. You won't need a compass -- the Big Dipper can show you
North. If you have a star chart to help you, take a flashlight.
Paint the glass with red nail polish, because red light will not blind your
eyes for the stars as white light will. Binoculars can help study
individual objects --- the moon, planets, etc., but to spot a whole
constellation, they restrict vision too much. Telescopes, too
are good to study individual planets, etc. But for most star study you can
do without both binoculars and telescopes.
With the naked eye you can see about two thousand stars at one time on a
clear night, though it seems like millions. There are about thirty which
are particularly bright or interesting. There are only 88 constellations
in the entire sky. About 60 can be seen from our area, and only about 24
are visible at a time. If you get to know 30 constellations, the most
important ones, you have a good knowledge of the sky. The other
constellations are mostly small, with no bright stars. They will in the
space between the more important ones. As you study, you will probably
become familiar with some of them.
TO FIND THE NORTH STAR:
First you must find the Big Dipper, then
draw an imaginary line between the two stars at the end of the bowl (where
water would pour out). Extend this imaginary line about five times as long
as the space between the two stars, and it will reach the North Star, or
Pole Star. The Pole Star is the only star which keeps its place in the sky.
All the other stars and constellations go around the pole once a day,
counterclockwise. However, the stars do not change positions in relation
to each other. The stars are "Fixed Stars", in contrast to the Planets,
which change position.
CIRCUMPOLAR CONSTELLATIONS:
The Big Dipper, Cassiopeia, the Little
Dipper, Cepheus, Draco the Dragon, and the Giraffe are not far from the
Pole Star. They can be high or low in the sky, but they are always above
the horizon, and can be seen at any time of the year.
The rest of the constellations also travel around the pole once a day, but
part of the time they do go below the horizon. They rise in the eastern
part of the sky, travel across, and set in the western part. They are out
of sight for some periods of the year. That's why you can't see Orion in
May, or the Lion in November. Scorpius (seen low in the south in the
summer), and Orion (also seen in the south, but in the winter), are two
of our most beautiful constellations. Some constellations can not be seen
because they are below the horizon. The famous Southern Cross, for
instance, can be seen in Argentina, Australia, and New Zealand, but don't
look for the Big Dipper there --- it would be out of sight.
MAGNITUDE:
The lower the figure of magnitude, the brighter the
star. There are 21 1st Magnitude stars --- they are the ones you
can't fail to see. Not quite as bright are the 2nd Magnitude. There are
about 50 of these. Polaris, the Pole Star is one of them. 3rd Magnitude
stars are still fairly bright. There are about 150 of them. All 1st, 2nd,
and 3rd Magnitude, and more than 600 4th Magnitude stars are plainly visible
on clear nights. Stars of 5th Magnitude are the faintest ones you see under
good conditions, about 1500, but most do not appear on the star charts.
Those that do, together with brighter stars, help form a distinct shape in
such constellations as the Dolphin, the Cup, and the Fishes, among others.
With binoculars or telescope, you can see many fainter stars.
Stars differ not only in brightness, but also in color. At first glance
they may all appear silvery white, but a closer look shows them to be
bluish, reddish, yellowish, or greenish. Example: Vega is bluish, and
Arcturus is orangeish.
We have often heard of the famous Halley's Comet, but we have one now
which they say is far brighter. Comet Hale-Bopp should attain its maximum
brightness in March and early April.
-- by Dot K. Platt
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