Intergalactic Extinction in the Local Supercluster. I. Selective Extinction

Abstract

An analysis of 566 color residuals & (B - V) of 262 normal galaxies observed at McDonald Observatory between 1960 and 1968 indicates that galaxies close to the supergalactic plane have a significant color excess averaging +0.03 mag in the center sector (northern galactic hemisphere) and +0.01 mag in the anticenter sector. The estimated total optical depth of the Local Supercluster in its equatorial plane is 0.2 to 0.3 mag in blue light.