00h48m00s, −25° 17′00″| Sculptor group | |
|---|---|
| |
| Observation data (Epoch J2000) | |
| Constellation(s) | Sculptor/Cetus |
| Right ascension | 00h48m [1] |
| Declination | −25° 17′[1] |
| Brightest member | Sculptor Galaxy (NGC 253)[2][3][4] |
| Number of galaxies | 13[2][3] |
| Other designations | |
| NGC 253 Group, LGG 4, Sculptor Filament,[3] South Polar Group, South Galactic Pole Group[4] | |
| See also: Galaxy group, Galaxy cluster, List of galaxy groups and clusters | |
The Sculptor Group is a loose group of galaxies[2][3] visible near the south galactic pole.[1] The group is one of the closest groups of galaxies to the Local Group; the distance to the center of the group from the Milky Way is approximately 3.9 Mpc (12.7 Mly).[3]
The Sculptor Galaxy (NGC 253) and a few other galaxies form a gravitationally-bound core in the center of this group. A few other galaxies at the periphery may be associated with the group but may not be gravitationally bound. Because most of the galaxies in this group are actually weakly gravitationally bound, the group may also be described as a filament.[2][3] It is considered to be at an early stage of evolution in which galaxies are still falling into the group along filamentary structures.[5]
The table below lists galaxies that have been identified as associated with the Sculptor Galaxy (and hence associated with the group) by I. D. Karachentsev and collaborators.[2][3]
| Name | Type[6] | R.A. (J2000)[6] | Dec. (J2000)[6] | Redshift (km/s)[6] | Apparent Magnitude[6] |
|---|---|---|---|---|---|
| IC 1574 | IM(s)m | 00h43m 03.8s | −22° 14′ 49″ | 363 ± 4 | 15.1 |
| NGC 59[5] | SA(rs)0 | 00h15m 25.1s | −21° 26′ 39.8″ | 362 ± 10 | 13.1 |
| NGC 247 | SAB(s)d | 00h47m 08.5s | −20° 45′ 37″ | 156 ± 2 | 9.9 |
| NGC 625 | SB(s)m | 01h35m 04.6s | −41° 26′ 10″ | 396 ± 1 | 11.7 |
| NGC 7793 | SA(s)d | 23h57m 49.8s | −32° 35′ 28″ | 227 ± 2 | 10.0 |
| PGC 2881 | IABm | 00h49m 20.9s | −18° 04′ 32″ | 16.5 | |
| PGC 2933 | IAB(s)m pec | 00h50m 24.3s | −19° 54′ 24″ | 16.6 | |
| PGC 6430 | IB(s)m | 01h45m 03.7s | −43° 35′ 53″ | 391 ± 2 | 12.7 |
| Sculptor-dE1[5] | dE | 00h23m 51.7s | −24° 42′ 18″ | 16.9 | |
| Sculptor Dwarf Irregular Galaxy (PGC 621) |
IBm | 00h08m 13.4s | −34° 34′ 42″ | 221 ± 6 | 15.5 |
| Sculptor Galaxy (NGC 253) |
SAB(s)c | 00h47m 33.1s | −25° 17′ 18″ | 243 ± 2 | 8.0 |
| UGCA 15 | IB(s)m | 00h49m 49.2s | −21° 00′ 54″ | 295 ± 0 | 15.2 |
| UGCA 442 | SB(s)m | 23h43m 45.5s | −31° 57′ 24″ | 267 ± 2 | 13.6 |
The object names used in the above table differ from the names used by Karachentsev and collaborators. NGC, IC, UGC, and PGC numbers have been used when possible to allow for easier referencing.
The irregular galaxy NGC 55, the spiral galaxy NGC 300, and their companion galaxies have been considered by many researchers to be part of this group. However, recent distance measurements to these and other galaxies in the same region of the sky show that NGC 55, NGC 300, and their companions may simply be foreground galaxies that are physically unassociated with the Sculptor Group.[2] The galaxies NGC 24 and NGC 45 are located in the vicinity of the Sculptor Group, but are now considered background objects.[7]
