NGC 6421
| Asterism | |
|---|---|
| NGC 6421 | |
| Constellation | Scorpio |
|
Position equinox : J2000.0 |
|
| Right ascension | 17h 45m 44.2s |
| declination | -33 ° 41 ′ 34 ″ |
| Further data | |
| Angular expansion |
45.0 ' |
| distance |
4900 ly (1505 pc) |
| history | |
| discovery |
John Herschel |
| Date of discovery |
August 3, 1834 |
| Catalog names | |
| NGC 6421 • GC3702 • h 4324 • ESO 393 - ** 22 | |
| Aladin previewer | |
NGC 6421 is one of several stars of existing asterism in the constellation Scorpio . It was discovered on August 3, 1834 by John Herschel during an observation in which he said "a most remarkable, well insulated, semi-nebulous milky way patch of a branching rounded figure, within the limits of the field, quite insulated on the preceding, north and following side, and only connected on the southern side by a narrow isthmus with a brnach of the milky way, which runs meriodionally to a great extent. It forms a VI class cluster of the utmost tenuity, barely resolvable, not resolved ”, mistakenly mistaken for a star cluster and thus achieved an entry in the catalog.
Web links
- NGC 6421. DSO Browser, accessed August 1, 2016 .
- Hartmut Frommert: Revised NGC Data for NGC 6421. SEDS, accessed on August 1, 2016 (English).
Individual evidence
- ↑ NASA / IPAC EXTRAGALACTIC DATABASE
- ↑ AL Tadross: A catalog of 120 NGC open star cluster . In: Journal of the Korean Astronomical Society , 44, 2011, pp. 1-11. doi: 10.5303 / JKAS.2011.44.1.1 .
- ↑ Seligman
- ↑ Auke Slotegraaf: NGC 6421. Deep Sky Observer's Companion, accessed on August 1, 2016 (English).