The nearby damped Lyα absorber SBS 1543+593:: A large HI envelope in a gas-rich galaxy group

We present a Very Large Array H (I) 21 cm map and optical observations of the region around one of the nearest damped Ly alpha absorbers beyond the Local Group, SBS 1543 + 593. Two previously uncataloged galaxies have been discovered, and a redshift has been determined for a third. All three of these galaxies are at the redshift of SBS 1543 + 593 and are less than or similar to 185 kpc from the damped Ly alpha absorber. We discuss the H (I) and optical properties of SBS 1543 + 593 and its newly identified neighbors. Both SBS 1543 + 593 and RBTB 154542.8 + 591132 have baryonic components that are dominated by neutral gas - unusual for damped Ly alpha absorbers, for which only similar to 5% of the H (I) cross section originates in such strongly gas-dominated systems. What remains unknown is whether low-mass gas-rich groups are common surrounding gas-rich galaxies in the local universe and whether the low star formation rate in these systems is indicative of a young system or a stable, slowly evolving system. We discuss these evolutionary scenarios and future prospects for answering these questions.