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Orion is my favorite. No constellation except for Ursa Major contains so many bright stars but in Orion they are shaped into a delicate balanced still life in the Winter sky.
Orion’s brightest star is 0.1 magnitude beta Orionus – also called Rigel. Rigel, which means "leg" in Arabic, is a blue-white giant about 900 light years from the Earth. Orion's second brightest star is 0.5 magnitude alpha Orinous – Betelgeuse – is a red super-giant 300 light years away. Betelgeuse is a French corruption of the Arabic expression for either the "house of the twins" or perhaps the less delicate but more accurate "arm pit". A red super-giant is formed when a star similarly sized to our Sun runs out of fuel and expands enormously while cooling down. By comparing Rigel to Betelgeuse you can get a good idea what a “red” star really looks like.
If you have a telescope, you can sere the beautiful Horsehead nebula near zeta Orionis which is the left most of the three stars of Orion's belt. Even more impressive are the two Messier objects M42 and M43 which are located next to each other in the middle of the trapezoid formed by Orion’s belt and two feet. They form the end of a sword hanging down from Orion’s belt. These objects are a vast cloud of gas and dust which serve as a "nursery" for newly formed stars. is a fine object for binoculars and can be seen with the naked eye under favourable conditions.
Orion according to Greek mythology was the son of Poseidon. In Hebrew Orion was known as "Gibur" (for hero) or "Nimrod" or simply "Kislev" which is a Winter month when Orion can easily be seen.
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