Have you ever watched this video? Carl Sagan really, really rocks!
Symphony of Science – ‘We Are All Connected’ (ft. Sagan, Feynman, deGrasse Tyson & Bill Nye)
Watch Cosmos TV Series by Carl Sagan at www.hulu.com/cosmos
I wanted to post the picture here but I have to ask for permission. So, I am posting the link: http://blogs.discovermagazine.com/badastronomy/2010/05/03/not-all-halos-are-created-equal/