Saturday, 23 April 2016 17:01

Seeing Double

Here we have HD79210, a double star located 20 light years away in the constellation Ursa Major. The pair of stars orbit each other once every 975 years. The primary star is a magnitude 7.64, and the secondary star is 7.70, so they both about the same brightness. They both are slightly cooler of the Sun, being K, and M class stars which are orange-red dwarf stars.

Many stars have orbiting companions, most are too far away, or orbit too close to see, other than by spectroscopic observation. Our Sun is in the minority in that it has no known stellar companions.

 

 Imaged under a full Moon, using 120 second exposures for each red, green, and blue filters.

 

 

Published in Stars