Andromeda Galaxy M31
- The Andromeda Galaxy, M31, is a spiral galaxy ~2.5 million light-years
away (see doi:10.1086/499161)
in the constellation Andromeda.
- A galaxy is a large collection of stars, gas and dust
moving as a identifiable, isolated system under the influence of gravity.
Our own Milky Way and the Andromeda galaxy will start to collide
about four billion years from now, merging over the
following two billion years -- NASA.
(It is thought that
the earth is about 4.5 billion years old, and that
life on earth originated over three billion years ago
- A constellation is a group of stars that appear to be
close in the (2D) sky, but are likely to be far apart in 3D.
- In Greek mythology, Andromeda was chained to a rock and left
to be eaten by a sea monster; Perseus rescued her.