Groups and Clusters of Galaxies with Messier objects
Galaxies are usually members of
groups or clusters, and those listed in Messier's
catalog are no exceptions. Below please find those groups containing Messier
galaxies. 
Groups of Galaxies containing at least two Messier objects
Ordered roughly by Right Ascension.
- 
  Local Group of Galaxies
 - 
  Messier objects:
  The Andromeda Galaxy
  M31
  and its satellites
  M32
  and
  M110,
  as well as the Triangulum galaxy
  M33.
  Other members (over 30 in all) include our 
  Milky Way Galaxy, the
  Large and the 
  Small Magellanic Cloud 
  (LMC and 
  SMC), as well as several
  smaller galaxies.  It is also somehow associated with the 
  
  group around the large elliptical Maffei1.
 - 
  M81 group
 - 
  Messier objects:
  M81
  and
  M82.
  This group is very nearby, only some 11 million light-years distant.
  Other members include 
  NGC 3077 and 
  NGC 2976, an outlying member of the
  group is NGC 2403.
 - 
  M96 group (Leo I group)
 - 
  Messier objects:
  M95,
  M96,
  M105.
  There are many more galaxies in this group, including NGC 3384 in the 
  same field as M105.
 - 
  Leo triplett (M66 group)
 - 
  M65 (NGC 3623),
  M66 (NGC 3627)
  and NGC 3628.  
  Probably physically related to the M96 group.
 - 
  Ursa Major Cloud
 - 
  Messier objects (probable members):
  M108,
  M109. 
  A large and vast cloud of galaxies of at least 79 member galaxies.
 - 
  Virgo Cluster of Galaxies 
  (or Coma-Virgo Cluster)
 - 
  Messier objects:
  M49,
  M58,
  M59,
  M60,
  M61,
  M84,
  M85,
  M86,
  M87,
  M88,
  M89,
  M90,
  M91,
  M98,
  M99,
  and
  M100.
  The Virgo Cluster with its some 2000 member galaxies dominates our
  intergalactic neighborhood, as it represents the physical center of our
  Local Supercluster, and influences all the galaxies and galaxy groups
  by the gravitational attraction of its enormous mass.  Our Local Group
  has experienced a speed-up of 100..400 km/sec towards this cluster
  (the Virgo-centric flow), and it is still unclear if at one time it will
  fall and merge into the cluster.  HST observations of Cepheids in M100,
  together with the work of 
  Nial R. Tanvir on the
  M96 group extrapolated to this cluster,
  indicate that the Virgo cluster is at a distance of some 60 million
  light-years.
 - 
  M51 group
 - 
  Messier objects: 
  M51,
  M63.
 - 
  M94 Group, CVn I Cloud
 - 
  Messier objects:
  M64,
  M94.
  This vast and loose group or cloud of galaxies is listed by various sources
  but not in R. Brent Tully's Nearby Galaxies Catalog.
 
Further Messier galaxies contained in groups
The following list contains the Messier galaxies which are members of 
groups but not listed above; usually, some info on the corresponding 
groups is included in the object pages for these galaxies. It is ordered
roughly by Right Ascension again.
- M74 is probably the chief member of a small 
  physical group of galaxies 
  (the M74 group)
 - M77 is the dominating member of a small but
  remarkable group of galaxies, the
  M77 group (sometimes also called
  the NGC 1068 group).
 - M106 is the brightest member of the
  Canes Venatici II (CVn II) group or
  M106 group of galaxies
 - M104 is the dominating member of a small 
  group called the M104 group or
  NGC 4594 group of galaxies.
 - M83 forms the
  M83 group together with some
  conspicuous but quite southern galaxies, including 
  Centaurus A (NGC 5128) 
  and the unusual galaxy NGC 5253.
  This group is sometimes also referred to as Centaurus A group or
  NGC 5128 group.
 - M101 forms the
  M101 group of at least 
  9 galaxies with several faint companions.
  Some sources suppose some physical connection with the M51 group but this
  is doubtful.
 - The M102 candidate
  NGC 5866 is the brightest member of a 
  conspicuous group of galaxies in Draco, the 
  NGC 5866 group, which 
  contains (besides NGC 5866) the bright edge-on spiral 
  NGC 5907, NGC 5879,
  and a lot of fainter galaxies.
 
Links:
Hartmut Frommert
Christine Kronberg
[contact]
Last Modification: November 14, 2004