Xi Ursae Majoris

[jude_rook]

27 light years out, this is one of those multiple-star systems that is just plain neat.  Not one but two G0V stars, each with its own M-class companion star!  Star A only appears to be about 2 billion years old, though.  B is older at around 6 billion years, but its companion appears to be in such a tight orbit around it that it would interfere with the orbital stability of anything in the life zone.  Too bad, although B could play host to a planet inhabited by life forms who thrived under colder conditions...