NGC 4848 | |
---|---|
Observation data ( J2000 epoch) | |
Constellation | Coma Berenices |
Right ascension | 12h 58m 05.6s [1] |
Declination | +28° 14′ 34″ [1] |
Redshift | 0.023513 ± 0.000033 |
Heliocentric radial velocity | 7,049 ± 10 km/ s [1] |
Distance | 340 ± 15 Mly (104 ± 4.5 Mpc) [1] |
Group or cluster | Coma cluster |
Apparent magnitude (V) | 13.7 [2] |
Characteristics | |
Type | SBab: sp [1] |
Apparent size (V) | 1.6′ × 0.5′ [1] |
Notable features | Hydrogen tail |
Other designations | |
UGC 8082, MCG +05-31-039, CGCG 160-055, PGC 44405, 5C 04.058 [1] |
NGC 4848 is a barred spiral galaxy in the constellation Coma Berenices. It is circa 340 million light-years from Earth, which, given its apparent dimensions, means that NGC 4848 is about 170,000 light years across. It was discovered by Heinrich d'Arrest on April 21, 1865. [3] It is considered part of the Coma Cluster, which is in its northwest part. The galaxy has been stripped of its gas as it passed through the cluster. [4]
NGC 4848 is a spiral galaxy viewed nearly edge-on that is classified as SBab by de Vaucouleurs. Its nucleus is active, and it has been categorised as an HII region. [5] A number of bright HII regions form a ring around the nucleus with a radius of 5–10 arcseconds. The star formation rate is estimated to be 9 M☉ per year based on the H-alpha, ultraviolet, infrared and radio luminosity. [4]
The galaxy distribution of hydrogen gas is asymmetrical and forms a tail pointing away from the cluster center. The tail has projected dimensions of 62.5 by 18.5 kpc and an estimated hydrogen mass of 4×109 M☉. The tail was probably formed as a result of ram pressure as the galaxy passed through the Coma Cluster and its intergalactic medium at a speed of about 1,330 km/s, starting 200 million years ago according to Fossati et al., [4] while a previous study indicated a timeline of 400 million years. [6] The lost hydrogen is estimated to comprise two thirds of the original hydrogen content of the galaxy. [6] A few star-forming regions, probably HII regions, are in the tail. [4]
A dwarf galaxy may cross the disk of NGC 4848; however, its mass is too low to be a source of the hydrogen tail. [6]