UGC 8058, Mrk 231, Mkn 231, Markarian 231, MCG+10-19-004, ZW VII 490, PGC 44117
Markarian 231 (UGC 8058) is a Type-1 Seyfert galaxy that was discovered in 1969 as part of a search of galaxies with strong ultraviolet radiation. It contains the nearest known quasar.[4] Markarian 231 is located about 581 million light years away from Earth, in the constellation of Ursa Major.
Markarian 231 is undergoing an energetic starburst. A nuclear ring at the center has an active rate of star formation of greater than 100 solar masses per year. It is one of the most ultraluminous infrared galaxies, with power derived from an accreting black hole in the center forming the closest known quasar. X-ray data shows the energy released from the black hole produces ultra-fast outflows with a velocity of -20,000 km s-1.[5]
A 2015 study suggested the central black hole of 150 million solar masses has a black hole companion of 4 million solar masses, and that they orbit each other every 1.2 years.[8] That model has been shown to be unfeasible.[9]
SpaceRef Feb 23, 2011 Quasar's Belch Solves Longstanding Mystery, from Gemini North Observatory, ApJ March 2011, to be published.
Chang-Shuo Yan, Youjun Lu, Xinyu Dai, and Qingjuan Yu. "A probable milli-parsec supermassive binary black hole in the nearest quasar MRK 231" 2015 August 14 The Astrophysical Journal, Vol. 809, Iss. 2 doi:10.1088/0004-637X/809/2/117