Sombrero Galaxy | |
---|---|
Observation data (J2000 epoch) | |
Constellation | Virgo |
Right ascension | 12h 39m 59.4s[1] |
Declination | −11° 37′ 23″[1] |
Redshift | 0.003416±0.000017[1] |
Heliocentric radial velocity | 1,024±5 km/s[1] |
Galactocentric velocity | 904±7 km/s[1] |
Distance | 9.55 ± 0.31 Mpc (31.1 ± 1.0 Mly)[2] |
Apparent magnitude (V) | 8.0[3][4] |
Absolute magnitude (B) | −21.8[5] |
Characteristics | |
Type | SA(s)a[1] or E[6] |
Size | 32.32 by 17.45 kiloparsecs (105,400 by 56,900 light-years) (diameter; 2MASS K-band total)[1] 29.09 kiloparsecs (94,900 light-years) (diameter; D25.0 B-band isophote)[1] |
Apparent size (V) | 9′ × 4′[1] |
Notable features | Unusually bright center, intriguingly detailed dust band |
Other designations | |
M104, NGC 4594, UGC 293, PGC 42407 |
The Sombrero Galaxy (also known as Messier Object 104, M104[4] or NGC 4594) is a peculiar galaxy of unclear classification[6] in the constellation borders of Virgo and Corvus, being about 9.55 megaparsecs (31.1 million light-years)[2] from the Milky Way galaxy. It is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster.[7] It has an isophotal diameter of approximately 29.09 to 32.32 kiloparsecs (94,900 to 105,000 light-years),[1] making it slightly bigger in size than the Milky Way.
It has a bright nucleus, an unusually large central bulge, and a prominent dust lane in its outer disk, which is viewed almost edge-on. The dark dust lane and the bulge give it the appearance of a sombrero hat (thus the name). Astronomers initially thought the halo was small and light, indicative of a spiral galaxy; but the Spitzer Space Telescope found that the halo was significantly larger and more massive than previously thought, indicative of a giant elliptical galaxy.[8]
The galaxy has an apparent magnitude of +8.0,[4] making it easily visible with amateur telescopes, and is considered by some authors to be the galaxy with the highest absolute magnitude within a radius of 10 megaparsecs of the Milky Way.[5] Its large bulge, central supermassive black hole, and dust lane all attract the attention of professional astronomers.