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
Hubble Space Telescope (HST) image of the galaxy
Observation data (J2000 epoch)
Constellation	Coma Berenices
Right ascension	12h 58m 05.6s[1]
Declination	+28° 14′ 34″[1]
Redshift	0.023513 ± 0.000033
Helio 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]

Characteristics

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]

See also

• NGC 4921, a spiral galaxy in the Coma Cluster that has lost its hydrogen

References

External links

• Media related to NGC 4848 at Wikimedia Commons

• NGC 4848 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images

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