On the Classification of UGC 1382 as a Giant Low Surface Brightness Galaxy

We provide evidence that UGC 1382, long believed to be a passive elliptical galaxy, is actually a giant low surface brightness (GLSB) galaxy that rivals the archetypical GLSB Malin 1 in size. Like other GLSB galaxies, it has two components: a high surface brightness disk galaxy surrounded by an extended low surface brightness (LSB) disk. For UGC 1382, the central component is a lenticular system with an effective radius of 6 kpc. Beyond this, the LSB disk has an effective radius of ~38 kpc and an extrapolated central surface brightness of ~26 mag arcsec^(−2). Both components have a combined stellar mass of ~8 × 10^(10) M_⊙, and are embedded in a massive (10^(10) M_⊙) low-density (