Page 30, The Milky Way and Other Galaxies

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Our LOCAL GROUP of Galaxies

Let's review our local group of galaxies, to set the scale for the larger clusters of galaxies we will study. Our LOCAL GROUP spans a region nearly 10 Million Light Years (Mly) in diameter.

This diagram shows some of the main members. There are 41 members in all. With the exception of M31, the Milky Way, and M33, the remaining 38 members are dwarf ellipticals or small irregular galaxies. New galaxies are still being found! A list is kept on http://www.seds.org/messier/more/local.html. Nearly all these dwarf and irregular galaxies would be undetected far from the Local Group.

Some important members of our Local Group include:

NGC 6822.
Irregular galaxy about 1.7 Mly away. This galaxy shows a lot of recent bursting of young massive stars (blue stars and red nebular areas). WLM.
This dwarf galaxy is about 4 Mly away. It is 1/12th the size of the Milky Way.

The Small Magellanic Cloud.
This irregular galaxy is very near, just 0.2 Mly away and has lots of massive stars. Leo I.
This is a dwarf elliptical galaxy 0.6 Mly away. It is a very diffuse grouping of stars and not easily found.

	NGC 6822. Irregular galaxy about 1.7 Mly away. This galaxy shows a lot of recent bursting of young massive stars (blue stars and red nebular areas).		WLM. This dwarf galaxy is about 4 Mly away. It is 1/12th the size of the Milky Way.
	The Small Magellanic Cloud. This irregular galaxy is very near, just 0.2 Mly away and has lots of massive stars.		Leo I. This is a dwarf elliptical galaxy 0.6 Mly away. It is a very diffuse grouping of stars and not easily found.