M81 in True Color . ... Credit Copyright: Gregory Bothun ( U. Oregon ), Courtesy Bill Keel ( U. Alabama ) Explanation: Here's what a spiral galaxy REALLY looks like. ... M81 is actually a dominant member of a group of galaxies which includes M82 and several other galaxies. Unlike our Local Group of galaxies, large galaxies in the M81 group are actually colliding . It is possible that M81's interaction with M82 create the density waves which generate M81's spiral structure. ...