HCG 23
| HCG 23 | |
|---|---|
 |
|
| SDSS uptake of HCG 23 (not labeled: PGC 11690 immediately above NGC 1215) | |
|
Observation dates equinox : J2000.0 , epoch : J2000.0 |
|
| Constellation | Eridanus |
| Right ascension | 03 h 07 m 06 s |
| declination | −9 ° 35.1 ′ 0 ″ |
| Angular expansion | approx. 7 ′ |
| Physical data | |
| Redshift | approx. 0.016 |
| Radial velocity | approx. 4800 km / s |
| distance | approx. 210 million light years approx. 65 million parsecs |
| Catalog names | |
| HCG 23, SCG 11 | |
HCG 23 is a compact group of galaxies in the constellation Eridanus in the southern sky. It is around 210 million light years from the Milky Way. Examination of the radial velocity distribution of hydrogen around the group suggests that it could be part of a larger, loose group.
The three NGC objects NGC 1214 , NGC 1215 and NGC 1216 are members of HCG 23 . The NGC entries for all three objects go back to an observation by Ormond Stone on October 12, 1886. NGC 1214 and NGC 1215 were independently discovered by Lewis A. Swift on October 21, 1886.
Members (selection)
| HCG |
α J2000.0 |
δ J2000.0 |
Morphological type | m V | Angular expansion | Position angle | Distance ( million years ) | Catalog names | |
|---|---|---|---|---|---|---|---|---|---|
| 23a | 03 h 06 m 56.0 s | −9 ° 32 ′ 39 ″ | S0-a | 14.1 | 1.3 ′ × 0.3 ′ | 40 ° | 216 | NGC 1214, PGC 11675, MCG -02-08-51, spar 66A | |
| 23b | 03 h 07 m 09.4 s | −9 ° 35 ′ 34 ″ | SBc | 14.1 | 1.8 ′ × 1.2 ′ | 65 ° | 216 | NGC 1215, PGC 11687, MCG -02-08-55, spar 66B | |
| 23c | 03 h 07 m 18.5 s | −9 ° 36 ′ 46 ″ | S0-a | 15.1 | 0.8 ′ × 0.2 ′ | 65 ° | 238 | NGC 1216, PGC 11693, MCG -02-08-56 | |
| 23d ( PGC 11673 ) |
03 h 06 m 55.2 s | −9 ° 37 ′ 42.9 ″ | Sd | 16.7 | 0.2 ′ × 0.1 ′ | 198 | MCG-02-08-50 | ||
| 23e ( PGC 11690 ) |
03 h 07 m 10.4 s | −9 ° 34 ′ 36.5 ″ | Sm | 17.8 | 0.4 ′ × 0.1 ′ | 447 | MCG-02-08-54 | ||
literature
- RR de Carvalho, ALB Ribeiro & Stephen E. Zepf (1994): Structural properties of compact groups ; in: Astrophysical Journal Supplement Series 93 (1), p. 47ff.
- BA Williams & JH van Gorkom (1995): HI Mapping of Compact Groups ; in: O.-G. Richter & K. Borne (Eds.): ASP Conference Series 70 (Groups of Galaxies), 77ff.
Web links
- JE Hibbard, JH van Gorkom, Michael P. Rupen & David Schiminovich: An HI Rogues Gallery. Interacting triples