M37 (NGC 2099) is a open cluster located within the constellation Auriga, in the Perseus Arm of the Milky Way Galaxy. in the Local Group of galaxies.
M37 is best viewed during winter, is magnitude 6.0*, and can be viewed with naked eye (just barely). It is 24' 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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