The Sky This Month
Welcome to our night-time sky.
Please enjoy this monthʼs tidbits
of knowledge. We are lucky to
live in a dark-sky area where
the heavens can shine through. I
hope you enjoy the sky and per-
haps learn a thing or two. Happy
star gazing!Bright and Dark – Itʼs
all variable. One of the more
famous variable stars in the sky is easily visible in
the November evenings. The star is Delta Cephei. So
named, because it is the fourth brightest star in the Ce-
pheus constellation (alpha, beta, gamma, delta…). By
convention, the brightness order of the star is named
corresponding to each subsequent letter in the Greek
alphabet, starting with the brightest star: Alpha. (To be
honest, I do not know what happens when they reach
omega.) In any case, Delta Cephei is a variable star,
which means that its brightness changes from darker
to brighter, and back again. The star varies every 5.37
days from magnitude 3.48 to 4.37, which is fairly dark
either way. The brightness varies because the star is
expanding and contracting by about 30%. To find the
star, look high in the sky towards the North and locate
Cassiopeia, which looks like a W on its side (or an M
on its other side). At the top of the W, follow an imagi-
nary line to the left. You should see three dim stars that
form a small triangle. The star closest to Cassiopeia is
Delta Cephei.
Queen of Aethiopia – (Apparently they spelled
Ethiopia differently back then.) Anyway, they had a
queen named Cassiopeia. She was known for her van-
ity and boasted that she was more beautiful than the sea
nymphs. This of course angered Poseidon (not a good
idea) who then forced her to forever wheel around the
North Pole on her throne, spending half the time cling-
ing to the throne upside down, trying not to fall off.
As noted previously, Cassiopeia is the W turned on its
side. If you look at the top of the W as an arrowhead
and follow it to the right this time, you will come to
the Andromeda Galaxy. You will not be able to see
Andromeda with your naked eye unless it is extremely
dark, clear, and you have excellent vision. Otherwise,
grab a pair of binoculars, and you should be able to
make out a blur of stars. Andromeda is the daughter of
See Sky, page 10
pccnews
November 2017
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