M23 (NGC 6494)
Messier M23 (NGC 6494) is a open cluster located in the constellation Sagittarius, in the Orion Arm of the Milky Way Galaxy. in the Local Group of galaxies.
Messier M23 is best viewed during late summer, is magnitude 6.0*, and can be viewed with naked eye (just barely). It is 27' 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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