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Focus on stars Betelgeuse and Rigel in Orion


Tonight for December 2, 2014

Most constellations have only one bright star, but the majestic constellation Orion the Hunter can boast of two: Rigel and Betelgeuse. Even in the glare of the evening moon, you can’t miss these two brilliant beauties if you look eastward around 8 to 9 p.m. Rigel and Betelgeuse reside on opposite sides of Orion’s Belt – three medium-bright stars in a short, straight row.

Photo of the constellation Orion by jpstanley

Rigel depicts Orion’s left foot. A blue-white supergiant and one of the most luminous stars known, it is nearly 800 light-years away. If it were as close as Sirius, the brightest star visible to the eye (and only about 8.6 light-years away), Rigel would shine much more brilliantly than Venus, our sky’s brightest planet.

Rigel: Orion’s brightest star

Betelgeuse – the other bright star in Orion – is the Hunter’s right shoulder. A red supergiant, Betelgeuse is no slouch of a star either. In fact, if Betelgeuse replaced the sun in our solar system, its outer layers would extend past Earth and Mars and to nearly the orbit of Jupiter.

Image credit: jpstanley

Betelgeuse will explode someday

On a moonless night, or after the moon sets in the wee hours before dawn, you might want to look at the magnificent Orion Nebula, or M42, the fuzzy patch in Orion’s Sword. Although the moon will light up the evening sky until it turns full on December 6, look for Orion’s two brilliant stars, Betelgeuse and Rigel, to have the firepower to withstand the onslaught of the waxing moon.