Detection of a second optical component in the H I cloud of the young dwarf galaxy SBS 0335-052 : New observations with the 6-m telescope

The Blue Compact Dwarf (BCD) galaxy SBS 0335–052 is one of the most metal–deficient galaxies known and one of the best candidates for a young dwarf galaxy in the process of formation. A VLA HI map reveals an unusual structure: the neutral gas is distributed in a very extended disk, about 15 times larger than the Holmberg optical diameter of the BCG. There are two peaks of high density. The eastern peak is close to the position of SBS 0335–052 whereas the western HI peak is associated with a faint compact optical galaxy. A 6–m telescope spectrum of this object shows H, H, and [OIII]5007 emission with a redshift close to that of SBS 0335–052. We suggest that it may be a young and chemically unevolved dwarf galaxy.