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Messier Index/M23
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Messier 23 250px w:J2000 I,2,r 17h 56.8m −19° 01′ 2.15 kly 659 Pc 6.9 27.0′ 8 220 million yearsFebruary 2007 Sagittarius NGC 6494
Messier 23 (also known as NGC 6494) is an w:open cluster in the w:constellation Sagittarius. It was discovered by w:Charles Messier on w:June 20, w:1764.
M23 is at a distance of about 2,150 w:light-years away from w:Earth, its radius is around 15-20 w:light years. There are some 150 identified members in this cluster, the brightest being of magnitude 9.2. M23 can be found with a modestly sized w:telescope in the rich starfields of the Sagittarius w:Milky Way.
External links
Messier 23, SEDS Messier pages