Orion (constellation)

Orion
Constellation
Orion
AbbreviationOri
GenitiveOrionis
Pronunciation/ɒˈr.ən/
SymbolismOrion, the Hunter
Right ascension5h
Declination+5°
QuadrantNQ1
Area594 sq. deg. (26th)
Main stars7
Bayer/Flamsteed
stars
81
Stars with planets10
Stars brighter than 3.00m8
Stars within 10.00 pc (32.62 ly)8
Brightest starRigel (β Ori) (0.12m)
Messier objects3
Meteor showersOrionids
Chi Orionids
Bordering
constellations
Gemini
Taurus
Eridanus
Lepus
Monoceros
Visible at latitudes between +85° and −75°.
Best visible at 21:00 (9 p.m.) during the month of January.
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Orion is a prominent set of stars visible during winter in the northern celestial hemisphere. It is one of the 88 modern constellations; it was among the 48 constellations listed by the 2nd-century astronomer Ptolemy. It is named after a hunter in Greek mythology.

Orion is most prominent during winter evenings in the Northern Hemisphere, as are five other constellations that have stars in the Winter Hexagon asterism. Orion's two brightest stars, Rigel (β) and Betelgeuse (α), are both among the brightest stars in the night sky; both are supergiants and slightly variable. There are a further six stars brighter than magnitude 3.0, including three making the short straight line of the Orion's Belt asterism. Orion also hosts the radiant of the annual Orionids, the strongest meteor shower associated with Halley's Comet, and the Orion Nebula, one of the brightest nebulae in the sky.