Auriga - The Charioteer

The Constellation Auriga the Charioteer 10x 4 minute lights stacked to create this image. Taken on the 24th January 2017 from our backyard using my Canon 600D DSLR with an EOS 18-55mm. lens at f=45mm. all mounted on a Star Adventurer equatorial mount.

Not sure whether the blurriness of the detail in this image was caused by too long an exposure of each frame (4mins) or poor manual focussing by myself. Either way the open clusters M36, M37 and M38 show in this images as amorphous blue blotches rather than individual stars. I shall point my 66mm. refractor at these open star clusters and make them the subject of a future post.

The bright star centre-left top is Alpha Aurigae also known as Capella. To the naked eye I always think Capella looks yellow in colour although in my image it appears white.

Updated image having used software to bring out the winter Milky Way which runs through this constellation

 Although Capella appears to be a single star to the naked eye, it is actually a star system of four stars in two binary pairs. The first pair consists of two bright, type-G giant stars, designated Capella Aa and Capella Ab, in a very tight circular orbit some 0.76 AU apart and a derived orbital period of 104 days. Capella Aa is the brighter of the two at spectral class G8III (G8 Giant) whereas Ab is slightly smaller and of spectral class G0III (G0 Giant). Aa has a calculated mass of 3.05 times that of the Sun and Ab some 2.57 times that of the Sun. These two stars have both exhausted their core hydrogen fuel and become giant stars, though it is unclear exactly what stage they are on the stellar evolutionary pathway. The second pair, around 10,000 astronomical units from the first, consists of two faint, small and relatively cool red dwarfs. They are designated Capella H and Capella L. 

 The Capella system is relatively close, at only 42.8 light-years (13.1 pc) from the Sun.

Credit: Wikipedia