- in 1936, the term Local Group was coined by Edwin Hubble to describe the cluster of nearby galaxies to which the Milky Way galaxy belongs.
- there are 43 galaxies now identified as belonging to the Local Group, more than half of which have only been discovered during the last 30 years.
- all of the galaxies in the Local Group interact gravitationally.
- in addition to the Milky Way, there are two other spiral galaxies in the Local Group, the Andromeda Galaxy (M31) and the smaller M33.
- our galaxy and M31 together contain over 99 percent of the mass of the Local Group.
- all of the other member of the Local Group are dwarf galaxies, of which the best known are the Large Magellanic Cloud and the Small Magellanic Cloud.
- some of the dwarf galaxies are so dim that their brightness is less than that of the night sky, making them difficult to detect.
- the Milky Way had 13 dwarf galaxies that orbit around it in the small way moons orbit around a planet.
- the Sagittarius dwarf galaxy is so close that it is in the process of being absorbed into the Milky Way.
Sagittarius Dwarf Irregular Galaxy
- the Local Group is also interacting with nearby groups of galaxies – it had stretched the Sculptor Group so much that there is no gap of intergalactic space between them. (see belwo for infographic.)
Local Group – Sculptor
- on an even larger scale, the Local Group is slowing falling towards the nearby Virgo Cluster of galaxies.