ORION (or OARION), in Greek mythology, son of Hyrieus or Poseidon, a mighty hunter of great beauty and gigantic strength. He is also sometimes represented as sprung from the earth. He was beloved of Eos, the dawn-goddess, who carried him off to Delos ; but Artemis slew him with her arrows (Odyssey, v. 121). According to other accounts which attribute Orion's death to Artemis, the goddess herself loved him and was deceived by the angry Apollo into shooting him by mistake ; or he paid the pen alty of offering violence to her, or of challenging her to a con test of quoit-throwing (Apollodorus i. 4 Horace, Odes, iii. 4, 71). In the lower world his shade is seen by Odysseus driving the wild beasts before him as he had done on earth (Odyssey, xi. 572). After his death he was changed into the constellation which is called by his name. It took the form of a warrior, wearing a girdle of three stars and a lion's skin, and carrying a club and a sword. When it rose early it was a sign of summer; when late, of winter and stormy weather; when it rose about midnight it heralded the season of vintage.
See Kiientzle's article in Roscher's Lexikon; Preller-Robert, Griech ische Mythologie PP.
Orion is one of the most conspicuous constellations, contain ing many bright stars. Of these Betelgeuse is easily distinguished by its yellowish-red colour in contrast to all the other important stars of the constellation which are white B-type stars. Betel geuse is an irregular variable sometimes above and sometimes below the first magnitude. It was the first star for which the apparent diameter was measured by Michelson's interferometer method (192o). Rigel at the opposite corner of the quadrilateral is rather brighter; and the third brightest star is Bellatrix. The Orion nebula can be seen with the naked eye just below the belt ; faint extensions of it have been photographed filling prac tically the whole constellation. The multiple star 0 Orionis is near the centre of the nebula. There is no doubt that the princi pal stars of the constellation form a single system, and are in volved in the nebulosity whose luminescence is stimulated by their intense radiation rich in light of short wave-length. The distance of the nebula is estimated at i8o parsecs.