logo
A Sense of Scale Page 8

Local Group, 5 million light years

1

What is called the Local Group extends to a region with a radius of 5 million light years. Besides the Milky Way it contains two other similar sized galaxies, the Andromeda (M31) and Triangulum (M33) galaxies. The Triangulum galaxy is also referred to as the Pinwheel Galaxy.

The Local Group also contains about 50 dwarf galaxies. There could be more, but because they are so faint several may not have been yet discovered. The number of stars within this region is estimated at 700 billion.

Image: Atlas of the Universe

 

5 million light years corresponds in our scale model with 47 million km, which is one third of the real distance to the Sun.

The Andromeda galaxy is in our scale model almost 24 million km away.

 

M31: The Andromeda Galaxy
is about 2.5 million light years away.
Image Robert Gendler, NASA POD.