The M101 Group, one of many in the Virgo Supercluster, is located in Ursa Major and named after the brightest galaxy in the group, the Pinwheel Galaxy (M101). The group is composed mostly of members that are companions of the Pinwheel Galaxy.
The M51 Group and the NGC 5866 Group are M101′s closest neighbor. The distances between these groups are similar which suggest the three groups are part of a single large, loose, elongated group. However, most identification methods consider them separate.