Template:Short description Template:Galaxy cluster
The M101 Group is a loose group of galaxies located in the constellation Ursa Major. The group is named after the brightest galaxy in the group, the Pinwheel Galaxy (M101). Most of the other members of the group are companions of the Pinwheel Galaxy.<ref name="garcia1993" /><ref name="giuricinetal2002" /><ref name="nbg">Template:Cite book</ref><ref name="fouqueetal1992">Template:Cite journal</ref> The group itself is one of many located within the Virgo Supercluster (i.e. the Local Supercluster).<ref name="tully1982">Template:Cite journal</ref>
MembersEdit
The table below lists galaxies that have been consistently identified as group members in the Nearby Galaxies Catalog,<ref name="nbg" /> the survey of Fouque et al.,<ref name="fouqueetal1992" /> the Lyons Groups of Galaxies (LGG) Catalog,<ref name="garcia1993" /> and the three group lists created from the Nearby Optical Galaxy sample of Giuricin et al.<ref name="giuricinetal2002" />
| Name | Type<ref name="ned">{{#invoke:citation/CS1|citation | CitationClass=web
}}</ref> |
R.A. (J2000)<ref name="ned" /> | Dec. (J2000)<ref name="ned" /> | Redshift (km/s)<ref name="ned" /> | Apparent Magnitude<ref name="ned" /> |
|---|---|---|---|---|---|---|
| Pinwheel Galaxy (M101) | SAB(rs)cd | Template:RA | Template:DEC | 241 ± 2 | 8.3 | |
| NGC 5204 | SA(s)m | Template:RA | Template:DEC | 201 ± 1 | 11.7 | |
| NGC 5474 | SA(s)cd pec | Template:RA | Template:DEC | 273 ± 9 | 11.3 | |
| NGC 5477 | SA(s)m | Template:RA | Template:DEC | 304 ± 5 | 14.4 | |
| NGC 5585 | SAB(s)d | Template:RA | Template:DEC | 293 ± 2 | 11.2 | |
| UGC 8837 | IB(s)m | Template:RA | Template:DEC | 144 ± 3 | 13.8 | |
| UGC 9405 | Im | Template:RA | Template:DEC | 222 ± 6 | 17 |
Other possible members galaxies (galaxies listed in only one or two of the lists from the above references) include the irregular galaxies NGC 5238 and UGC 8508.
Nearby groupsEdit
The M51 Group, which includes the Whirlpool Galaxy (M51) and the Sunflower Galaxy (M63),<ref name="garcia1993" /><ref name="giuricinetal2002" /><ref name="nbg" /><ref name="fouqueetal1992" /> is located to the southeast of the M101 Group, and the NGC 5866 Group is located to the northwest.<ref name="ferrareseetal00">Template:Cite journal</ref> The distances to these three groups (as determined from the distances to the individual member galaxies) are similar, which suggests that the M51 Group, the M101 Group, and the NGC 5866 Group are actually part of a single large, loose, elongated group.<ref name="ferrareseetal00" /> However, most group identification methods (including those used by the references cited above) identify these three groups as separate entities.