Capella is the most northerly of the first magnitude stars. In brightness it is virtually equal in brightness to Vega which occupies the overhead point in summer a position that is occupied by Capella in winter.
Capella or alpha Aurigae is the brightest star in the constellation of Auriga the Charioteer, it is also the 6th brightest star in the sky. In mythology Auriga is said to represent Erechthonius, son of Vulcan, the blacksmith of the gods who invented the four horse chariot.
Capella means the ‘She-Goat’ and just below Capella is a triangle of three stars called the kids a very prominent feature of the winter skies and a sure sign that the star you think you are looking at really is Capella.
Capella is a G3 yellow giant star lying at a distance of 43 light years. In 1899 astronomers discovered that Capella is a double star , the second star referred to as Capella b is also a yellow giant star. The two stars orbit each other every 104 days. There is also a pair of red dwarfs that orbit at a distance of around about 1 light year.
Over the years it was thought that there were five other stars in the Capella system, however astronomers have now discovered that these stars are merely line of sight stars and are not connected with Capella.
Capella also appears to be one of the brightest sources of X Rays in the sky, this is thought to come from Capella a.