| NGC 4491 | |
|---|---|
 SDSS image of NGC 4491. | |
| Observation data (J2000epoch) | |
| Constellation | Virgo |
| Right ascension | 12h 30m 57.1s[1] |
| Declination | 11° 29′ 01″[1] |
| Redshift | 0.001658/497 km/s[1] |
| Distance | 55,420,000ly[2] |
| Group orcluster | Virgo Cluster |
| Apparent magnitude (V) | 13.5[1] |
| Characteristics | |
| Type | SB(s)a[1] |
| Size | ~7,140 ly (estimated)[1] |
| Apparent size (V) | 1.7 x 0.9[1] |
| Other designations | |
| PGC 41376, UGC 7657, VCC 1326[1] | |
NGC 4491 is adwarfbarred spiral galaxy[2] located about 55 millionlight-years away[3] in theconstellationVirgo.[4] NGC 4491 was discovered by astronomerWilliam Herschel on March 15, 1784.[5] NGC 4491 is located in a subgroup of theVirgo Cluster centered onMessier 87 known as theVirgo A subgroup.[2]
NGC 4491 is a strongly barred galaxy. The bar may have grown from the tidal influence of other galaxies in theVirgo Cluster.[2]
The infrared-radio properties of NGC 4491 possibly suggest the presence of anAGN in the galaxy. However, spectral analysis of the galaxy does not support this view since emission lines are absent or very weak and narrow.[2]
