Orion

(astronomy) A northern constellation near the celestial equator, right ascension 5 hours, declination 5° north. Also known as Warrior.

The Warrior, in astronomy, and undoubtedly the finest of all constellations in the sky. Orion is a winter group near the celestial equator. Four of the most prominent stars, α, γ, β, and κ, form a huge crude rectangle (see illustration). The group is pictured as the figure of a warrior, holding a shield with his left hand and swinging a club with his raised right arm ready to strike the charging Bull. Betelgeuse (meaning armpit), one of the largest stars known, is the red star at the right shoulder, Bellatrix is at the left shoulder, and Rigel, the blue-white star, is at the left leg. Three bright stars in a straight line in the middle of the rectangle represent the warrior's belt. The center star is Alnilam. See also Constellation; Orion Nebula.

Line pattern of the constellation Orion. M42 designates the Orion Nebula. The grid lines represent the coordinates of the sky. The apparent brightness, or magnitude, of the stars is shown by the size of the dots, graded by appropriate numbers.