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Star Cluster

Messier 21 :
open star cluster

Messier 21 is a open star cluster located in the constellation Sagittarius . Messier 21 is magnitude 5.90*, and is 14' in size. For reference, the full moon is 30' (arc minutes) or 0.5° in size.

      1. Name:
      2. Messier 21
      1. Type:
      2. open cluster
      1. Magnitude (m):
      2. 5.90
      1. Size:
      2. 14'
      1. Right Ascension:
      2. 18h 04.2m
      1. Declination:
      2. -22° 29'
      1. Messier #:
      2. M21

    * One can see up to magnitude 7-8 objects with perfect eyes under ideal dark sky conditions.



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