Caption: The Local Group of Galaxies shown with 1 megalight-year (Mly) = 0.306601393 ... Mpc linear scale.

The radius of the largest circle is ∼ 5 Mly ≅ 1.5 Mpc.

Features:

1. The Local Group is a galaxy group: i.e., a gravitationally bound system of galaxies of order 50 or fewer members of luminosity >∼ the luminosity of the Milky Way (i.e., ∼ 10**10 solar luminosities L_☉ = 3.828*10**26 W). Local Group is actually a poor galaxy group since it has only 3 of the galaxy group defining luminosity: see below.

2. The Local Group has a size scale of ∼ 3.1 Mpc ≅ 10 Mly and has a sort of dumbbell shape.

3. The Local Group is part of the Virgo Supercluster which is probably part of the larger Laniakea Supercluster.

4. The Local Group comprises at least 80 galaxies, most of which are dwarf galaxies.

5. There is NOT yet an exact count of galaxies in the Local Group since there may still be undiscovered dwarf galaxies hidden from our view by the interstellar dust in the Milky Way galactic disk (FK-593) and also because the status of some objects is NOT clear: i.e., dwarf galaxy or star cluster (e.g., Willman 1). There is a distinction between a dwarf galaxy and star cluster even if they have comparable size and mass. A galaxy by definition has had multiple generations of star formation although it may now be a quenched galaxy (i.e., a galaxy with star formation turned off). On the other hand, a star cluster had all its star formation in a relatively short time compared to cosmic time: i.e., a few millions of years (see Wikipedia: Star cluster: Embedded cluster; Wikipedia: Embedded cluster).

6. Clearly, NOT all Local Group members are shown or labeled in the image. For obvious example, the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) are NOT shown They are probably too close to the Milky Way to be easily displayed.

7. As aforementioned, there are only 3 large galaxies of the galaxy group defining luminosity, all spirals:
   1. The Milky Way (AKA The Galaxy).
   2. The Andromeda Galaxy (M31, NGC 224, distance = 0.778(33) Mpc = 2.54(11) Mly).
   3. The Triagulum Galaxy (M33, NGC 598, distance = 0.835(105) Mpc = 2.72(35) Mly).
   Example dwarf galaxy members are:
   1. Antlia Dwarf.
   2. Aquarius Dwarf.
   3. Canes Venatici I Dwarf.
   4. Canis Major Dwarf.
   5. Cetus Dwarf.
   6. Fornax Dwarf.
   7. Large Magellanic Cloud (LMC).
   8. Pegasus Dwarf Irregular Galaxy.
   9. Pegasus Dwarf Spheroidal Galaxy (AKA Pegasus II, Andromeda VI).
   10. Phoenix Dwarf.
   11. Small Magellanic Cloud (SMC).
   12. Tucana Dwarf.

   The 3 large galaxies are visible to the naked eye: Milky Way is, of course, the milky band on the sky and the other two just look like cloudy stars (i.e., nebulae in the historical sense: historical nebulae).

   Of the dwarf galaxies, yours truly thinks only the Magellanic Clouds are naked eye astronomical objects, and of course, they are invisible circumpolar objects relative to mid northern latitudes since they are sufficiently far south on the southern celestial hemisphere. They look like unconnected bits of the Milky Way to the naked eye (see Wikipedia: Magellanic Clouds: Characteristics). For the appearance of the Magellanic Clouds on the sky, see the figure below (local link / general link: milky_way_magellanic_clouds.html).

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8. The Local Group is gravitationally bound as indicated above. The members orbit the center of mass which in direction of the Andromeda Galaxy to within a few degrees at ∼ 0.5 Mpc from the Milky Way and at ∼ 0.3 Mpc from the Andromeda Galaxy (Whiting 2014).

9. The orbits of the Local Group members are NOT closed orbits and are all probably somewhat chaotic.

10. Many gigayears in the future, the Local Group will probably coalesce into a cD galaxy (AKA supergiant elliptical galaxy). The first major step in coalescence is probably the Andromeda-Milky Way collision (∼ 3.75 Gyr after present).