NGC 6216
| AladinLite | |
| Constellation | Scorpio |
|
Position equinox : J2000.0 |
|
|---|---|
| Right ascension | 16 h 29 m 23.6 s |
| declination | -44 ° 43 ′ 54 ″ |
| Appearance
|
|
| classification | II2p |
| Brightness (visual) | 10.1 mag |
| Angular expansion | 4.0 ′ |
| Physical data
|
|
| distance | 14000 ly (4300 pc ) |
| history | |
| Discovered by | James Dunlop |
| Discovery time | May 13, 1826 |
| Catalog names | |
| NGC 6216, 6222 • C 1645-446 • Mel 152 • Cr 314 • Dun 454 • ESO 277-SC014 • GC 4237 • h 3648 • OCL 989, Bennett 81 | |
NGC 6216 is an open star cluster (type definition "II2p") in the constellation Scorpio . It was discovered on May 13, 1826 by James Dunlop with a 9-inch reflector telescope, who found it with "a faint nebula, about 4 'or 5' diameter, irregular round figure, easily resolvable into stars; with stars of larger magnitudes scattered in the preceding side of it ”.
In 1834, John Herschel noted in the course of several observations with an 18-inch reflector telescope:
June 1: “A pretty rich cluster of small stars, 11th mag and under, broken up into two or three groups; fills two-thirds of field "
July 1:" a round cluster of 13th mag stars, gradually brighter in the middle; 4 ′; with two appendages of stars, north and south, making together a long cluster "
July 27:" pretty rich, round, pretty compressed in the middle, very little brighter in the middle, 4 ′ diameter, stars discrete 12th. 15th mag and fainter "
On the night of June 3, 1834 he noted under his own number 3650 with a slightly different position the observation “very large, very rich cluster, not brilliant, not materially compressed in the middle, full 20 'diameter, stars 12..13th mag ". Dreyer gave this object the catalog number NGC 6222 , modern astronomy today mostly assumes a double observation.
Web links
- NGC 6216. SIMBAD, accessed July 1, 2016 .
- NGC 6216. DSO Browser, accessed July 1, 2016 .
- Auke Slotegraaf: NGC 6216. Deep Sky Observer's Companion, accessed July 1, 2016 .