Messier M31 - Andromeda Galaxy
M31 (NGC 224), also known as Andromeda Galaxy, is a spiral galaxy located within the constellation Andromeda in the Local Group of galaxies.
M31 is best viewed during winter, is magnitude 4.5*, and can be viewed with naked eye. It is 178' in size. For reference, the full moon is 30' (arc minutes) in size.
* The naked eye can see up to magnitude 8 objects under ideal dark sky conditions.
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