Giant low surface brightness (GLSB) galaxies are among the most massive known
spiral galaxies in the Universe. They have very faint
stellar disks that are very rich in
neutral hydrogen but low in
star formation and thus low in surface brightness.
UGC 1382 was previously thought to be an elliptical galaxy, but low-brightness spiral arms were later detected. UGC 1382 is much closer to Earth than Malin 1. == Examples ==