Today:
Orion is in the south this evening, his left foot (on the right as we face him) denoted by the star Rigel, which is Arabic for “left foot”. The bright star that marks his right shoulder (on our left) is called Betelgeuse, also Arabic, though its meaning is less certain. Variations in the name suggest it means the hand, the shoulder, or the armpit.
Friday:
As Orion crests across the southern skies, his bright stars demonstrate considerably differences in color. Compare, for example, the star Betelgeuse on the upper left, appearing an orangish color, while on the lower right, Rigel shines a piercing blue. The colors indicate the star’s outer temperature, with red much cooler than the very hot blue.
Saturday:
Orion boasts a fine collection of bright stars, including the bluish-white beacon to the lower right of his three belt stars. Rigel, meaning “left foot”, is classified as a blue supergiant, estimated to be 860 light years, and emitting approximately 200 thousand times more light than the Sun.