The Andromeda Galaxy is regarded as the most distant object visible to the

human eye. It's a spiral galaxy in the constellation Andromeda. It's the nearest

external galaxy except for the Magellanic Clouds, which are companions of the

Milky Way Galaxy. It is 2.2 million light years away from Earth, and appears as

a fuzzy patch of light. It's diameter is approximately 200,000 light years. It also

shows characteristics similar to the Milky Way. The Andromeda Galaxy covers

over 3% of the sky on its largest side. This galaxy is the largest member of the

local group which includes the Milky Way and the Triangulum Galaxy. It has

twice as many stars as the Milky Way. The Andromeda Galaxy is a spiral galaxy

with fairly tight arms. Like the Milky Way, it has two prominent satellite

galaxies that are both small ellipticals.
 

    It was first mentioned in the "Book of the Fixed Stars." It was rediscovered

in 1612. For centuries astronomers regarded the Andromeda as a component of

the Milky Way Galaxy. In the 1920's the astronomer Edwin Powell Hubble

determined that the Andromeda was in fact a separate galaxy from the Milky

Way.