Figure 13-43 The M81 Group The Irr II starburst galaxy M82 is in a nearby cluster of about a dozen galaxies, including the spectacular spiral M81. Several of the galaxies in this cluster are connected by streamers of hydrogen gas. (a) The three brightest galaxies in the cluster at visual wavelengths. The inset on the left shows large volumes of hydrogen gas, in red, being ejected from M82. (b) This radio image, created from data taken by the Very Large Array, shows the streamers of hydrogen gas that connect the bright galaxies and also several dim ones, seen as regions of bright orange here.