Capella

Capella is the brightest star in the northern constellation of Auriga. It has the Bayer designation α Aurigae, which is Latinised to Alpha Aurigae and abbreviated Alpha Aur or α Aur. Capella is the sixth-brightest star in the night sky, and the third-brightest in the northern celestial hemisphere after Arcturus and Vega. A prominent object in the northern winter sky, it is circumpolar to observers north of 44°N. Its name meaning "little goat" in Latin, Capella depicted the goat Amalthea that suckled Zeus in classical mythology. Capella is relatively close, at 42.9 light-years (13.2 pc) from the Sun. It is one of the brightest X-ray sources in the sky, thought to come primarily from the corona of Capella Aa.
Although it appears to be a single star to the naked eye, Capella is actually a quadruple star system organized in two binary pairs, made up of the stars Capella Aa, Capella Ab, Capella H and Capella L. The primary pair, Capella Aa and Capella Ab, are two bright-yellow giant stars, both of which are around 2.5 times as massive as the Sun. The secondary pair, Capella H and Capella L, are around 10,000 astronomical units (AU) from the first and are two faint, small and relatively cool red dwarfs.
Category:Stars
Category:Star systems