Astronomy:Markarian 421

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Short description: Blazar located in the constellation Ursa Major
Markarian 421
Sloan Digital Sky Survey image of Mrk 421
Observation data (Epoch J2000)
ConstellationUrsa Major
Right ascension 11h 04m 27.314s[1]
Declination+38° 12′ 31.80″[1]
Redshift0.030021[1][2]
Distance397-434 million light-years
(122[2]-133[3] Mpc)
TypeBL 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. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 "Mrk 421". SIMBAD Astronomical Database. http://simbad.u-strasbg.fr/simbad/sim-id?Ident=Mrk+421. Retrieved 2010-04-12. 
  2. ↑ 2.0 2.1 2.2 2.3 2.4 "NASA/IPAC Extragalactic Database". Results for MRK 0421. http://nedwww.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=Mrk+421&extend=no. Retrieved 2010-04-12. 
  3. ↑ 3.0 3.1 "Distance Results for MRK 0421". NASA/IPAC Extragalactic Database. http://nedwww.ipac.caltech.edu/cgi-bin/nDistance?name=MRK+0421. Retrieved 2010-04-13. 
  4. ↑ "Variable Star Of The Season AAVSO. Winter 2004: Markarian 421". AAVSO. December 28, 2007. http://www.aavso.org/vsots_mark421. Retrieved 2010-01-10. 
  5. ↑ Punch, M.; Akerlof, Carl W.; Cawley, M. F.; Chantell, M.; Fegan, D. J.; Fennell, S.; Gaidos, J. A.; Hagan, J. et al. (6 August 1992). "Detection Of Tev Photons From The Active Galaxy Markarian 421, Nature, Volume 358, Issue 6386, pp 477-478 (Aug. 6, 1992)". Nature 358 (6386): 477. doi:10.1038/358477a0. Bibcode: 1992Natur.358..477P. 
  6. ↑ Gaidos, J. A.; Akerlof, C. W.; Biller, S.; Boyle, P. J.; Breslin, A. C.; Buckley, J. H.; Carter-Lewis, D. A.; Catanese, M. et al. (1996). "Extremely rapid bursts of TeV photons from the active galaxy Markarian 421, Nature, Volume 383, Issue 6598, pp. 319-320 (1996)". Nature 383 (6598): 319. doi:10.1038/383319a0. Bibcode: 1996Natur.383..319G. http://mural.maynoothuniversity.ie/12613/1/Cawley_burstTeVPhotons_1996.pdf. 
  7. ↑ Sillanpää, A.; Takalo, L. O.; Webt Collaboration (2001). "Optical monitoring of the blazar Mk421 during the TeV outburst". International Cosmic Ray Conference 7: 2699. Bibcode: 2001ICRC....7.2699S. http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2001ICRC....7.2699S&db_key=AST&data_type=HTML&format=&high=3df49e2f1329486. 

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