Auriga the Charioteer is a constellation prominent during winter in the Northern Hemisphere. Situated between the head of
Orion and the north celestial pole, it contains Capella, the sixth brightest star in the sky, three star clusters (M 36, M 37, and M 38) visible through binoculars, and several important double stars. One of the double stars, epsilon Aurigae, has a component 3,000 times the diameter of the Sun and eclipses its companion, causing a variation of magnitude from 3.7 to 4.5 over a
period of 27 years, the longest period of any known
eclipsing binary. The other double star, zeta Aurigae, is also an eclipsing binary. It is composed of a hot blue star and a red giant with a period of 972 days.