AN OPTICAL COUNTERPART TO THE H-I CLOUD IN THE LOCAL SUPERCLUSTER

We report the detection of an optical counterpart to the large H I cloud recently discovered by Giovanelli and Haynes in the Local Supercluster. The peak of the H I flux corresponds to a low surface brightness, dwarf irregular galaxy. The counterpart was discovered on a photographically amplified image from the UK Schmidt Telescope, and its maximum extent is 180″ at the 27 mag arcsec-2 isotope. We suggest that the H I and optical data can be explained by a pair of LSB dwarf irregular galaxies that have similar velocities. Some star formation appears to be taking place in this system, but the H I column density is below the threshold for extensive star formation. A kinematic study is required to determine the total mass. This galaxy is similar to other LSB dwarfs and dI pairs which have enormous mass-to-light ratios and H I sizes far in excess of the optical scale length.