M6 (NGC 6405) - Butterfly Cluster
Messier M6 (NGC 6405), also known as the Butterfly Cluster, is a open cluster located in the constellation Scorpius, in the Orion Arm of the Milky Way Galaxy. in the Local Group of galaxies.
Messier M6 is best viewed during mid-summer, is magnitude 4.2*, and can be viewed with naked eye. It is 15' 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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