Amateur astronomers often debate which globular cluster is the best, or prettiest.  I’m not sure I would enter into that debate even if I had an opinion, so I’ll stick to the facts:  Omega Centauri, also known as NGC5139, is the largest globular cluster in our galaxy.  Or at least the largest one visible from Earth.  Since these clusters are generally located outside the disk of the galaxy, they are not hidden behind the dense dust lanes of the disk, so it probably is the largest one. Located some 15,800 light-years from Earth in the constellation Centaurus, the apparent size […]