NGC 6451
AladinLite | |
Constellation | Scorpio |
Position equinox : J2000.0 |
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Right ascension | 17 h 50 m 40.6 s |
declination | -30 ° 12 ′ 42 ″ |
Appearance
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classification | II1p |
Brightness (visual) | 8.2 likes |
Angular expansion | 8.0 ′ |
Physical data
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Radial velocity | −23 km / s |
distance | 6800 ly (2080 pc ) |
history | |
Discovered by | Wilhelm Herschel |
Discovery time | June 24, 1784 |
Catalog names | |
NGC 6451 • Mel 181 • Cr 352 • ESO 455-SC50 • GC 4335 • H VI 13 • h 3707 • OCL 1035 |
NGC 6451 is an open star cluster (type definition "II1p") in the constellation Scorpio . It was discovered on June 24, 1784 by Wilhelm Herschel with an 18.7-inch reflector telescope, who described it as “a cluster of small and pretty compressed stars of several magnitudes, 5 ′ or 6 ′ diameter, not very rich” . During two observations with an 18-inch reflecting telescope, John Herschel noted “pretty rich, irregularly round, stars 13m, a cluster with a great black cut acorss it; 6 ′ diameter, with many outliers ”and“ a remarkable cluster, divided into two by a broad vacant straight band, irregularly round, 8 ′ diameter, stars 12..15m, See fig 6, Plate V ”.