Figure 14-23 The M81 Group (a) The irregular starburst galaxy M82 is shown close up in a nearby cluster of about a dozen galaxies, dominated by the spectacular spiral M81. (b) Several of the galaxies in this cluster are connected by streamers of hydrogen gas. This wide-angle visible-light photograph shows the three brightest galaxies of the cluster, dominated by M81. The area shown is about 1° across. (c) This false-color radio image of the same region, created from data taken by the Very Large Array, shows streamers of hydrogen gas that connect the three bright galaxies as well as several dim ones.