NGC 4638
Galaxy in the constellation Virgo
From Wikipedia, the free encyclopedia
NGC 4638 is an edge-on lenticular galaxy[2] located about 50 million light-years away[3] in the constellation Virgo.[4] NGC 4638 was discovered by astronomer William Herschel on March 15, 1784.[5] The galaxy is a member of the Virgo Cluster.[6][7]
| NGC 4638 | |
|---|---|
Sloan Digital Sky Survey image of NGC 4638. | |
| Observation data (J2000 epoch) | |
| Constellation | Virgo |
| Right ascension | 12h 42m 47.4s[1] |
| Declination | 11° 26′ 33″[1] |
| Redshift | 0.003843[1] |
| Heliocentric radial velocity | 1152 km/s[1] |
| Distance | 50.77 Mly (15.565 Mpc)[1] |
| Group or cluster | Virgo Cluster |
| Apparent magnitude (V) | 12.1[1] |
| Characteristics | |
| Type | S0[1] |
| Size | ~42,800 ly (13.13 kpc) (estimated)[1] |
| Apparent size (V) | 2.17 x 1.27[1] |
| Other designations | |
| NGC 4667, CGCG 70-229, CGCG 71-6, MCG 2-32-187, PGC 42728, UGC 7880, VCC 1938[1] | |
Structure
At the center of NGC 4638, there is a small bulge. There is also an edge-on disk and a diffuse, boxy halo. The shallow surface brightness gradient of the halo is characteristic of a large spheroidal galaxy. This means that NGC 4638 has properties of both S0 and Sph galaxies.[8]
