The M109 Group (also known as the NGC 3992 Group or Ursa Major cloud) is a group of galaxies about 55 million light-years awayThe Ursa Major Groups in the constellation Ursa Major. The group is named after the brightest galaxy within the group, the spiral galaxy M109.

Members

The table below lists galaxies that have been consistently identified as group members in the Nearby Galaxies Catalog, the survey of Fouque et al., the Lyons Groups of Galaxies (LGG) Catalogue, and the three group lists created from the Nearby Optical Galaxy sample of Giuricin et al.

+Members of the M109 Group Name Type R.A. (J2000) Dec. (J2000) Redshift (km/s) Apparent Magnitude Messier 109 SB(rs)bc 1048 ± 1 10.6 NGC 3718 SB(s)a pec 993 ± 1 11.6 NGC 3726 SAB(r)c 866 ± 1 10.9 NGC 3729 SB(r)a pec 1060 ± 1 12.0 NGC 3769 SB(r)b 737 ± 2 12.5 NGC 3782 SAB(s)cd 739 ± 6 13.1 NGC 3870 S0 756 ± 7 13.4 NGC 3877 Sc 895 ± 4 12.1 NGC 3893 SAB(rs)c 967 ± 1 11.2 NGC 3913 (R)SA(rs)d 954 ± 4 13.2 NGC 3917 SAcd 965 ± 1 12.5 NGC 3922 S0/a 906 ± 7 13.4 NGC 3928 SA(s)b 988 ± 4 13.0 NGC 3949 SA(s)bc 800 ± 1 11.5 NGC 3953 SB(r)bc 1052 ± 2 10.8 NGC 3972 SA(s)bc 852 ± 1 13.1 NGC 3982 SAB(r)b 1109 ± 6 12.0 NGC 4010 SB(s)d 902 ± 1 13.2 NGC 4026 S0 930 ± 40 11.7 NGC 4085 SAB(s)c 746 ± 5 13.0 NGC 4088 SAB(rs)bc 757 ± 1 11.2 NGC 4100 (R)SA(rs)bc 1074 ± 1 11.9 NGC 4102 SAB(s)b 846 ± 2 12.0 NGC 4142 SB(s)d 1157 ± 7 13.9 NGC 4157 SAB(s)b 774 ± 2 12.2 UGC 6628 SAm 841 ± 1 13.2 UGC 6667 Scd 973 ± 1 14.2 UGC 6840 SB(rs)m 1046 ± 5 14.3 UGC 6917 SBm 911 ± 1 13.1 UGC 6923 Im 1066 ± 2 15.1 UGC 6930 SAB(s)d 777 ± 0 12.7 UGC 6983 SB(rs)cd 1082 ± 1 13.1 UGC 7218 Im 770 ± 7 14.8

Galaxies frequently but not consistently listed as group members in the above references (i.e. galaxies listed in four of the above lists) include NGC 3631, NGC 3657, NGC 3733, NGC 3756, NGC 3850, NGC 3898, NGC 3985, NGC 3990, NGC 3998, NGC 4217, NGC 4220, UGC 6773, UGC 6802, UGC 6816, UGC 6922, and UGC 6969. The exact membership and the exact number of galaxies in the group is somewhat uncertain.

Fouque et al. lists these galaxies as two separate groups named Ursa Major I North and Ursa Major I South, both of which were used to compile the above table. Most other references, however, identify this as a single group, as is specifically noted in the LGG Catalogue.

References