Download Circumpolar constellations

CIRCUMPOLAR CONSTELLATIONS
The process of science:
The science of Astronomy usually begins with observation, often of phenomena that change over time.
Analyzing those observations, astronomers look for patterns that result from the Earth’s rotation on its axis
as well its revolution around the Sun. Observation requires patience, because some celestial motions take
long periods of time to repeat. You may not notice the slow, subtle change in the positions of the
constellations over an hour, but you will notice their positions change over three or four hours in one night.
And you will certainly notice their changing positions over a month.
Introduction:
Is there a direction you could look any clear night, no matter what time of year, and always see the same stars?
Yes! Circumpolar constellations do not rise or set, but appear to move in a series of circles around Polaris, the
pole star. In the northern hemisphere, between 30 and 40 degrees North latitude, there are five prominent
circumpolar constellations visible to us: Ursa Major, Ursa Minor, Cassiopeia, Cepheus and Draco.
Camelopardalis is also a circumpolar constellation, but its stars are very dim, and hard to spot.
Latitude matters when it comes to circumpolar constellations. If an observer is located about 38 degrees
north latitude, then all stars within 38 degrees of the north star will appear above the northern horizon and
move in a circular pattern around Polaris as the earth rotates on its axis. Observers at lower latitudes will
see Polaris lower in the northern sky, and fewer stars and constellations will appear as circumpolar. For
example, an observer at the equator (with a latitude = 0°) would observe Polaris due north at a point on the
horizon, and all the stars would rise in the East, and set in the West — none would be circumpolar.
Observers at higher latitudes also see Polaris higher in the northern sky, and will see more circumpolar
constellations. An observer at the north pole would observe Polaris at the zenith — the point directly over
your head. At the north pole, the whole sky would seem to be circumpolar! All of the stars would rotate
around in sky parallel to the horizon, never rising nor setting.
Perhaps the common names of the constellations are more familiar to you: The Big Dipper, The Little
Dipper, The Queen, The King and The Dragon. These common names refer more to the figures and shapes
apparently formed by the brighter stars within each constellation. A grouping of stars within a single
constellation, or across constellations, is called an asterism. For example, Ursa Major refers to the bear and
The Big Dipper refers to the seven bright stars in that constellation forming an old fashioned “dipper”. There
are many more stars in Ursa Major than the seven we see in the Dipper.
Circumpolar Constellations & Bright Stars
Constellation Name
URSA MAJOR
Asterism/ Mythological Figure
The Big Dipper
URSA MINOR
The Little Dipper
CASSIOPEIA
CEPHEUS
DRACO
CAMELOPARDALIS
The Queen of Ethiopia
The King
The Dragon
The Giraffe (“Camel-Leopard”)
Circumpolar Constellations
Brightest Star Names
Dubhe & Merak (the Pointers)
Alkaid (the end of the handle)
Polaris (the North Star)
Pherkad and Kochab
Caph & Schedar
Alderamin
Thuban
no bright stars to be seen
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