| NGC 4388 | |
|---|---|
 Hubble Space Telescope image of NGC 4388 | |
| Observation data (J2000epoch) | |
| Constellation | Virgo |
| Right ascension | 12h 25m 46.820s[1] |
| Declination | +12° 39′ 43.45″[1] |
| Redshift | 0.008419[2] |
| Heliocentric radial velocity | 2,524 km/s[2] |
| Distance | 56.7 Mly (17.4 Mpc)[3] |
| Group orcluster | Virgo Cluster[4] |
| Apparent magnitude (V) | 11.02[5] |
| Apparent magnitude (B) | 11.76[5] |
| Characteristics | |
| Type | SA(s)b[4] |
| Mass | 26.4+16.4 −10.1×109[3] M☉ |
| Size | 120 kly (36 kpc)[2] |
| Apparent size (V) | 6.2′ × 1.674′[2] |
| Other designations | |
| VCC 836, HOLM 403C,IRAS 12232+1256,UGC 7520,MCG +02-32-041,PGC 40581,CGCG 070-068[5] | |
NGC 4388 is anactivespiral galaxy in theequatorialconstellation ofVirgo. This galaxy is located at a distance of 57 millionlight years[3] and is receding with aradial velocity of 2,524km/s.[2] It is one of the brightest galaxies of theVirgo Cluster due to its luminous nucleus. NGC 4388 is located 1.3° to the west of the cluster center, which translates to a projected distance of≈400 kpc.[4] The NGC 4388 galaxy has been assigned amorphological class of SA(s)b, which indicates it is a spiral with no central bar (SA) or inner ring structure (s), and has moderately-woundspiral arms (b). It is inclined at an angle of 79° to the line of sight from the Earth and thus is being viewed from nearly edge-on. The major axis of the elliptical profile is aligned with aposition angle of 92°.[4] It was discovered April 17, 1784 byWilliam Herschel.[6]
Theinterstellar medium of the galaxy has recently undergone a stripping event due toram pressure, causingstar formation to steeply decline some190±30 Myr ago. The galaxy may have passed close to the cluster center around 200 Myr ago, which led to the loss of much of its neutral hydrogen from interaction with the inter-cluster medium.[4]
This is a classic Type 2Seyfert galaxy where the emission from the active galactic nucleus is being concealed by a torus of obscuring gas and dust.[7] Thesupermassive black hole at the core has a mass of(8.5±0.2)×106 M☉, which has a hot corona with a temperature energy of80+40
−20 keV that is producingX-ray emission.[8] There is a strong nuclear outflow to the north and south that extends out as far as5 kpc from the core. These flows have a mean velocity of270±70 km·s−1.[4]
NGC 4388 has a largeextended emission-line region (EELR) that has a length of around 35 kpc, stretching beyond the galaxy. This emission cloud is created when the supermassive black hole is active and its radiation ionizes gas from its galaxy. In the case of NGC 4388 it is suggested that the gas was first stripped from the galaxy either viatidal interaction or viaram pressure and later ionized.[9] A small H II region, known as theGAFO Region, ionised by a 3.3 million years old star cluster, is located within this region.[10]
Onesupernova has been observed in NGC 4388:SN 2023fyq (type Ibn, mag. 19.5 at discovery) was discovered by theZwicky Transient Facility on 17 April 2023.[11] The supernova brightened slowly from discovery until 24 July 2023, whenKōichi Itagaki photographed it at magnitude 13.3.[12] Originally classified as a type Ib-pec, it was later designated as type Ibn.[12]
Media related toNGC 4388 at Wikimedia Commons
