LSB galaxies

LSB galaxies

Short for low surface brightness galaxies. Galaxies with a very low central surface brightness that may be very common and contain much of the mass in the Universe. They are difficult to detect against the brightness of the night sky and are thus missing from most galaxy catalogs. They are thought to be unevolved systems, with central regions resembling a dwarf galaxy. Most of the mass is contained in a large gaseous disk that is observable only at radio wavelengths or with image-enhanced exposures. The galaxies are thus commonly referred to as icebergs. See Malin 1.