There are about 48 old constellations. Today astronomers recognize 88 (44 in each hemisphere) dividing all of the entire sky. THE GREAT BEAR AND THE SEVEN STARS
Probably the most famous group of stars is the Big Dipper. It is a part of the constellation called Ursa Major. It resembles a bear in many civilizations. The handle of the Dipper is the tail of the bear curving away from the bowl.
THE LITTLE BEAR AND POLARIS:
Five major constellations are always visible above the horizon from our latitudes: Ursa Minor, Ursa Major, Cassiopeia, Cepheus and Draco. They all revolve once in 24 hours around the North Star and stars in these are known as Circumpolar stars. Ursa Minor or the Little Bear is well known for being the host of Polaris, positioned very close to the celestial north pole. Actually the Polaris revolves in radius of 1 degree about the North celestial pole.
Polaris is the brightest star in the Ursa Minor. It is part of 7 well known stars similar to Big Dipper. The handle in it curves towards the bowl unlike Big Dipper.
Cassiopeia lies on the other side of the pole from Ursa Major, almost directly opposite the Big Dipper. One can sees the seven stars with naked eyes. Sometimes people visualize it as part of a Crown of the Egyptian queen Cassiopeia, other people see it as an inclined chair or throne.
NEXT TO CASSIOPEIA is her husband the king Cepheus, known for some of the well-studied variable stars. Cepheus forms a shape resembling the cap of a clown. Its wedge corner is very close to Polaris and is one of the circumpolar stars. The brightest star in this constellation is called Aldemarin, meaning the arm. It stays close to his queen.
Draco, the Dragon
Another famous constellation near the North Pole is Draco meaning Dragon placed beneath the Ursa Minor. It is the dragon that the giant Hercules faces up to. Two known stars in it are called Etamin (tip of Dragon's head) and Thuban in the tail (3rd last star) of the dragon. Etamin is 80 ly away.
THE ORION AND ITS BRIGHT STARS
Next to the Big Dipper, Orion is the most well known constellation of all. Its shape and group of bright stars dominate the winter sky. It contains more bright stars clustered together than any other single group. To the ancients, the figure represented the giant Orion, placed in the heavens, in a heroic gesture holding the shield against Taurus the mighty Bull. The bull on the other hand, with fire darting out from its eye (marked by Aldebaran), is about to charge with its splendid long horns. Orion stands with his right arm holding a great club uplifted in the air, ready to strike. Over his left arm hangs a lion's skin that he holds up as a shield before him to stop the raging bull. With a bit of imagination, it is not difficult to observe in this constellation, a colossal figure and a story behind it.
Orion contains two of the 1st magnitude bright stars, Betelgeuse and Rigel. Betelgeuse marks the right shoulder or armpit, while Rigel forms the left foot. First, the Betelgeuse rises, pushing its red face. Betelgeuse is a red giant, deep red in color. It is also known as an irregular Variable star, changing its brightness but not regularly. Rigel appears about 15 to 20 minutes after Betelgeuse. The Celestial equator lies between the two so that Rigel is a southern hemisphere star and Betelgeuse is a northern hemisphere star. With Aldebaran, the two form a triangle, called Winter triangle, dominating the winter sky. Except for Deneb, Rigel (1300 ly) and Betelgeuse (500 ly) are the most distant stars to reach us. Red and cooler the enormous Betelgeuse is 17,000 times brighter than sun. Rigel, blue-white and very hot although smaller than its sisters, nevertheless it is 150,000 times brighter than sun. The belt of Orion is made of three dazzling stars of 2nd magnitude that are referred to as "bands of Orion," by Job. These lie in a straight line three...
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