NGC 6253
| AladinLite | |
| Constellation | altar |
|
Position equinox : J2000.0 |
|
|---|---|
| Right ascension | 16 h 59 m 05.1 s |
| declination | -52 ° 42 ′ 32 ″ |
| Appearance
|
|
| classification | I3m |
| Brightness (visual) | 10.2 mag |
| Angular expansion | 4.0 ′ |
| Physical data
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| Radial velocity | −28 km / s |
| distance | 4900 ly (1510 pc ) |
| history | |
| Discovered by | James Dunlop |
| Discovery time | May 14, 1826 |
| Catalog names | |
| NGC 6253 • Mel 156 • Cr 321 • ESO 180-SC02 • GC 4255 • h 3657 • OCL 972 | |
NGC 6253 is an open star cluster (type definition "I3m") in the constellation Altar and about 4900 light years from Earth. It was discovered on May 14, 1826 by James Dunlop with a 9-inch reflector telescope, which found “a very faint nebula, of an irregular round figure, about 2 ′ diameter, slightly bright towards the center, easily resolvable into very minute stars , slightly compressed to the center; this also precedes Epsilon Arae ”noted. John Herschel described it during an observation with an 18-inch reflecting telescope with "a small triangular cluster, 2 ′ diameter, stars of 13th magnitude".