M31

The Andromeda Galaxy (sometimes also known by the old name Great Andromeda Nebula or by the catalog acronyms M 31 and NGC 224) is a large barred spiral galaxy that is about 2.538 million light years from Earth in the direction of the constellation Andromeda, from which it takes its name. This is the large galaxy closest to ours, the Milky Way; it is also visible to the naked eye and is among the most distant objects visible without the aid of instruments.

The Andromeda Galaxy is the largest of the Local Group, a group of galaxies which also includes the Milky Way and the Triangulum Galaxy, plus about fifty other minor galaxies, many of which are satellites of the main ones.