Markarian 231 (UGC 8058) is a Type-1 Seyfert galaxy that was discovered in 1969 as part of a search for galaxies with strong

ultraviolet Ultraviolet radiation, also known as simply UV, is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight and constitutes about 10% of ...

radiation. It is named after the Armenian astronomer Benjamin Markarian, who played an active role in identifying and cataloging a number of active galaxies during the 1960s. Markarian 231 contains the nearest known

quasar A quasar ( ) is an extremely Luminosity, luminous active galactic nucleus (AGN). It is sometimes known as a quasi-stellar object, abbreviated QSO. The emission from an AGN is powered by accretion onto a supermassive black hole with a mass rangi ...

and is located about 581 million light years away from

Earth Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...

, in the constellation of

Ursa Major Ursa Major, also known as the Great Bear, is a constellation in the Northern Sky, whose associated mythology likely dates back into prehistory. Its Latin name means "greater (or larger) bear", referring to and contrasting it with nearby Ursa M ...

Characteristics

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 The solar mass () is a frequently used unit of mass in astronomy, equal to approximately . It is approximately equal to the mass of the Sun. It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies ...

per year. It is one of the most ultraluminous

infrared Infrared (IR; sometimes called infrared light) is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those ...

galaxies, with power derived from an accreting

black hole A black hole is a massive, compact astronomical object so dense that its gravity prevents anything from escaping, even light. Albert Einstein's theory of general relativity predicts that a sufficiently compact mass will form a black hole. Th ...

in the center forming the closest known

X-ray An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ran ...

data shows the energy released from the black hole produces ultra-fast outflows with a

velocity Velocity is a measurement of speed in a certain direction of motion. It is a fundamental concept in kinematics, the branch of classical mechanics that describes the motion of physical objects. Velocity is a vector (geometry), vector Physical q ...

of −20,000 km s⁻¹. The galaxy contains a curved radio jet interacting with the

interstellar medium The interstellar medium (ISM) is the matter and radiation that exists in the outer space, space between the star systems in a galaxy. This matter includes gas in ionic, atomic, and molecular form, as well as cosmic dust, dust and cosmic rays. It f ...

. Its

position angle In astronomy, position angle (usually abbreviated PA) is the convention for measuring angles on the sky. The International Astronomical Union defines it as the angle measured relative to the Celestial pole, north celestial pole (NCP), turning pos ...

switches to −172^○ when reaching a projected distance of 25 pc. The Very Long Baseline Array found a triple radio source in Markarian 231. 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. That model has been shown to be unfeasible.

Submillimetre astronomy Submillimetre astronomy or submillimeter astronomy (see spelling differences) is the branch of observational astronomy that is conducted at submillimetre wavelengths (i.e., terahertz radiation) of the electromagnetic spectrum. Astronomers plac ...

has found evidence of molecular

oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...

(O2), the first time molecular oxygen has been detected outside of the

Milky Way galaxy The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galaxy, which are ...

. The

Herschel Space Observatory The Herschel Space Observatory was a space observatory built and operated by the European Space Agency (ESA). It was active from 2009 to 2013, and was the largest infrared telescope ever launched until the launch of the James Webb Space Telesco ...

showed

water vapor Water vapor, water vapour, or aqueous vapor is the gaseous phase of Properties of water, water. It is one Phase (matter), state of water within the hydrosphere. Water vapor can be produced from the evaporation or boiling of liquid water or from th ...

in the galaxy's emission.

References

External links

Markarian 231 at ESA
''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 ''The Astrophysical Journal'' (''ApJ'') is a peer-reviewed scientific journal of astrophysics and astronomy, established in 1895 by American astronomers George Ellery Hale and James Edward Keeler. The journal discontinued its print edition and ...

'', Vol. 809, Iss. 2 *http://www.cnn.com/2015/08/31/us/double-black-hole-nasa-hubble-feat/ *http://www.sci-news.com/astronomy/science-supermassive-binary-black-hole-markarian231-03180.html *http://dso-browser.com/dso/info/UGC/8058 Spiral galaxies Seyfert galaxies Luminous infrared galaxies 8058 Markarian galaxies 44117 Ursa Major {{Spiral-galaxy-stub

Characteristics

See also

References

External links