THE SOUTHWORTH PLANETARIUM
207-780-4249      www.usm.maine.edu/planet
70 Falmouth Street     Portland, Maine 04103
43.6667° N                   70.2667° W
Founded January 1970
Julian date:  2457724.16
           "Sent forward in time for your convenience."




THE DAILY ASTRONOMER
Thursday, December 1,, 2016
The Pointer Queen

Polaris is not the brightest star.    In fact, it ranks 48th in the list of
the sky's brightest stars, right after Alphard (in Hydra) and just before
Hamal (in Aries).   As it is one of the few well known stars, Polaris is
logically believe to also be the brightest.    It isn't.  Were it not for
its current position close to the North Celestial Pole, we might pay it
scant notice.  However, Polaris is the sky's stellar cynosure and thus all
stars appear to revolve around it.   It occupies a prominent position in
both the sky and our collective consciousness.

Polaris is also not directly overhead in our sky.  Only a north pole
observer would see it around the zenith.  (As Polaris is not precisely
aligned with the North Celestial Pole, it won't be precisely at the zenith
at the North Pole.  However. it would appear so close one couldn't tell the
difference.)      The observer's latitude determines the angle Polaris
subtends relative to the northern horizon.      An observer at 43 degrees
north latitude would find Polaris 43 degrees north of the northern horizon.
  An observer at 10 degrees north latitude would find it 10 degrees north
of the northern horizon.     No observer south of the equator could find
Polaris.

Well, if Polaris is not the brightest star and if it is not directly
overhead, how should one be expected to find it?          The answer to
this question depends on the time of year.     Now, in late autumn/early
winter, one can use Cassiopeia the Queen as a guide.   Like the Big Dipper,
Cassiopeia is circumpolar, meaning that it will never set, at least not at
this latitude.     Also -like the Big Dipper- Cassiopeia describes a wide
circle around Polaris every day.   Its position also shifts slightly each
day as a consequence of Earth's  revolutionary motion around the Sun.
Presently, Cassiopeia begins the evening near the zenith, while the Big
Dipper rests low on the northern horizon.    Six months from now -the first
day in June when the Sun soars high in azure skies and no sorrow is
possible- the Big Dipper begins the night at its top perch and the queen
cowers close to the horizon.

Cassiopeia's lofty position makes it an idea guide right now.   Just look
straight up after dusk darkens into night an you'll observe the beautiful
queen reclining at the apex.     Follow its stars toward Polaris, which
always remains in the same place.


*​The two guides.       The circumpolar constellations Cassiopeia and Ursa
Major can guide observers to find Polaris, the North Star.      Ursa
Major's most prominent feature is the "Big Dipper," an asterism consisting
of its seven brightest stars.    In the late autumn/early winter,
Cassiopeia starts the night high in the sky and can therefore easily guide
an observer to Polaris.   In the spring/summer, the Big Dipper is high in
the early evening and can serve as your "guide to Polaris."*

One can determine the cardinal points by first finding Polaris.      If one
is facing Polaris, one is looking north.   South is to the back.    East is
to the right and west to the left.       We know that our part of the
galaxy is teeming with objects and over populated with ancient
constellations.  Trying to find one's way in that celestial jungle is not
for the faint hearted.    However, by locating Polaris, one can get one's
bearings and the exploration will be all that less difficult.