NGC 4457
Galaxy in the constellation of Virgo
From Wikipedia, the free encyclopedia
NGC 4457 is an intermediate spiral galaxy located about 55 million light-years away[2] in the constellation of Virgo.[3] It is also classified as a LINER galaxy, a class of active galaxy defined by their spectral line emissions.[4][2] NGC 4457 Is inclined by about 33°.[5] It was discovered by astronomer William Herschel on February 23, 1784.[6] Despite being listed in the Virgo Cluster Catalog as VCC 1145,[7] NGC 4457 is a member of the Virgo II Groups[8][9][10] which form an extension of the Virgo cluster.[8][11]
| NGC 4457 | |
|---|---|
SDSS image of NGC 4457 | |
| Observation data (J2000 epoch) | |
| Constellation | Virgo |
| Right ascension | 12h 28m 59.0s[1] |
| Declination | 03° 34′ 14″[1] |
| Redshift | 0.002942[1] |
| Heliocentric radial velocity | 882 km/s[1] |
| Distance | 54,801,600 ly |
| Group or cluster | Virgo II Groups |
| Apparent magnitude (V) | 11.76[1] |
| Characteristics | |
| Type | (R)SAB(s)0/a, LINER[1] |
| Size | ~ 38,687.32 ly |
| Apparent size (V) | 2.7 × 2.3[1] |
| Other designations | |
| VCC 1145, IRAS 12264+0350, UGC 7609, MCG +01-32-075, PGC 41101, CGCG 042-124 [1] | |
NGC 4457 may have had a recent minor merger with another galaxy.[12]
Supernova
On July 1 2020, an astronomical transient was discovered in NGC 4457 by astronomer Kōichi Itagaki and confirmed by ASAS-SN. Spectroscopic classification determined the object to be a type Ia Supernova, designated SN 2020nvb.[13]
Physical characteristics
NGC 4457 has a broad oval zone containing an inner spiral which is defined mainly by two fairly open arms. There is a well-defined outer ring that is completely detached from the inner regions of the galaxy.[14]
Truncated disk
NGC 4457 has a severely reduced amount of star-formation in its disk while its inner regions have a normalized rate of massive star formation.[14] This may have been caused by a recent interaction of the gas in the galaxy with the gas in the surrounding Virgo Cluster,[15] causing the gas to be stripped away in an effect known as ram-pressure stripping.[16]
See also
- List of NGC objects (4001–5000)
- Messier 90
- Comet Galaxy - a distant galaxy in the cluster Abell 2667 which is experiencing ram-pressure stripping as well
