Markarian 421

Markarian 421
Hubble Legacy Archive WFPC2 image of Mark 421 and its companion galaxy 421-5
Observation data (Epoch J2000)
Constellation Ursa Major
Right ascension 11h 04m 27.314s[1]
Declination +38° 12 31.80[1]
Redshift 0.030021[1][2]
Distance 397-434 million light-years
(122[2]-133[3] Mpc)
Type BL LAC[1][2]
Apparent magnitude (V) 12.9 (SIMBAD)[1]
13.3 (NED)[2]
11.6-16 (B Band)[4]
Other designations
B2 1101+38, UGC 6132, PGC 33452, 2E 2393, QSO B1101+384, Mark 421[1]
See also: Quasar, List of quasars

Markarian 421 (Mrk 421, Mkn 421) is a blazar located in the constellation Ursa Major. The object is an active galaxy and a BL Lacertae object, and is a strong source of gamma rays. It is about 397 million light-years (redshift: z=0.0308 eq. 122Mpc)[2] to 434 million light-years (133Mpc)[3] from the Earth. It is one of the closest blazars to Earth, making it one of the brightest quasars in the night sky. It is suspected to have a supermassive black hole (SMBH) at its center due to its active nature. An early-type high inclination spiral galaxy (Markarian 421-5) is located 14 arc-seconds northeast of Markarian 421.

It was first determined to be a very high energy gamma ray emitter in 1992 by M. Punch at the Whipple Observatory,[5] and an extremely rapid outburst in very-high-energy gamma rays (15-minute rise-time) was measured in 1996 by J. Gaidos at Whipple Observatory [6]

Markarian 421 also had an outburst in 2001 and is monitored by the Whole Earth Blazar Telescope project.[7]

Due to its brightness (around 13.3 magnitude, max. 11.6 mag. and min. 16 mag.) the object can also be viewed by amateurs in smaller telescopes.

References

  1. 1 2 3 4 5 6 "Mrk 421". SIMBAD Astronomical Database. Retrieved 2010-04-12.
  2. 1 2 3 4 5 "NASA/IPAC Extragalactic Database". Results for MRK 0421. Retrieved 2010-04-12.
  3. 1 2 "Distance Results for MRK 0421". NASA/IPAC Extragalactic Database. Retrieved 2010-04-13.
  4. "Variable Star Of The Season AAVSO. Winter 2004: Markarian 421". AAVSO. December 28, 2007. Retrieved 2010-01-10.
  5. "Detection Of Tev Photons From The Active Galaxy Markarian 421, Nature, Volume 358, Issue 6386, pp 477-478 (Aug. 6, 1992)". Bibcode:1992Natur.358..477P. doi:10.1038/358477a0. Missing or empty |url= (help)
  6. "Extremely rapid bursts of TeV photons from the active galaxy Markarian 421, Nature, Volume 383, Issue 6598, pp. 319-320 (1996)". Bibcode:1996Natur.383..319G. doi:10.1038/383319a0. Missing or empty |url= (help)
  7. "Optical monitoring of the blazar Mk421 during the TeV outburst".

Coordinates: 11h 04m 27s, +38° 12′ 32″


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.