EPSILON ORIONIS

'Epsilon Orionis' (ε Ori / ε Orionis) is a large blue star in the constellation of Orion. It also has the traditional name 'Alnilam'. Its Flamsteed designation is '46 Orionis'.
It is the 30th brightest star in the sky (the 4th brightest in Orion) and as a blue-white supergiant it is one of the most luminious stars known. It is the middle star of Orion's belt.
It is also one of the 57 stars used in celestial navigation. For middle latitudes, it is at its highest point in the sky around midnight on December 15.
Alnilam's relatively simple spectrum has made it useful for studying the interstellar medium. Within the next million years, this star may turn into a red supergiant and explode as a supernova. It is surrounded by a molecular cloud, NGC 1990, which it brightens to make a reflection nebula. Its stellar winds may reach up to 2000 km/s, causing it to lose mass about 20 million times more rapidly than the Sun.

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Other names and history

See also

Other names and history

The name ''Alnilam'' derives from the Arabic 'النظام' ''an-niżām'', related to the word 'نظم' ''nażm'' "string of pearls". Related spellings are ''Alnihan'' and ''Alnitam'': all three variants are evidently mistakes in transliteration or copy errors.
Various other names have been used to refer to Orion's belt, the line of three stars formed by Alnitak, Alnilam, and Mintaka. They include:

★ The Weighing Beam (Chinese mythology)

★ Jacob's Staff, Peter's Staff, the Three Magi, or the Three Kings (the Bible)

★ Freya's Staff (Norse mythology)

★ Väinämöinen's Scythe (Kalevala)

★ Kalevan Sword (Finnish mythology)
These stars also allegedly influenced the construction of the Pyramids of Giza.

See also

★ Epsilon Orionis in fiction