Messier 18
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Messier 18 or M18, also designated NGC 6613 and sometimes known as the Black Swan Cluster, is an open cluster of stars in the constellation Sagittarius. It was discovered by Charles Messier in 1764 and included in his list of comet-like objects. Wikipedia
Radius: 9 light years
Distance to Earth: 4,892 light years
Apparent magnitude (V): 7.5
Declination: –17° 06′ 06″
Right ascension: 18h 19m 58.0s
Apparent dimensions (V): 9.8′
Mass: 186+161; −86 M☉