NGC 2992 is a Seyfert galaxy located 103[6] million light years distant in the equatorial constellation of Hydra. It was discovered in 1785 by Anglo-German astronomer William Herschel.[5]

NGC 2992
NGC 2992 (right) with its partner, NGC 2993 (left)
Observation data (J2000 epoch)
ConstellationHydra
Right ascension09h 45m 42.045s[1]
Declination−14° 19′ 34.90″[1]
Redshift0.00771[2]
Heliocentric radial velocity2,311 km/s[3]
Distance103 Mly (31.6 Mpc)[4]
Apparent magnitude (V)12.2[5]
Characteristics
TypeSa[5]
Mass55.7×109[4] M
Apparent size (V)3.24 × 0.91′[6]
Other designations
2MASX J09454204-1419348, NGC 2992, LEDA 27982, PGC 27982[7][6]

The morphological classification of this galaxy is Sa,[5] indicating a spiral with no central bar. The plane of the galaxy is inclined at an angle of 70° to the line of sight from the Earth,[2] so it is being viewed from nearly edge on. A prominent dust lane extends along the major axis, crossing the nucleus.[8] This was identified as a Seyfert galaxy in 1980 based on a broad component of the line with no matching broadening. It is classed as an intermediate[8] Seyfert of type 1.9/1.5.[2] Varying emission in the x-ray and other bands have been detected from the nucleus of NGC 2992, which may be the result of changes to an accretion disk in the core.[8] These fluctuations show changes by a factor of up to 20 on a time scales of days or weeks. The mass of the central supermassive black hole is estimated to be 5.2×107 M.[2]

The nearby companion galaxy NGC 2993 is located less than 3′ to the southeast of NGC 2292. The two are linked by a tidal bridge of ionized hydrogen and there are tidal tails to the southeast of NGC 2993 and the north of NGC 2292. The encounter between these galaxies may be the trigger for the active nucleus in NGC 2992. There is a significant amount of dust obscuring the nucleus and cones of material outflowing from the core at nearly right angles to the alignment of the galaxy.[9] NuSTAR observations suggest there is an ultra-fast outflow component with a velocity of 0.21±0.01 c.[2]

References

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  1. ^ a b Skrutskie, Michael F.; et al. (February 1, 2006). "The Two Micron All Sky Survey (2MASS)". The Astronomical Journal. 131 (2): 1163–1183. Bibcode:2006AJ....131.1163S. doi:10.1086/498708. ISSN 0004-6256. S2CID 18913331.
  2. ^ a b c d e Marinucci, A.; et al. (August 2018). "Tracking the iron K α line and the ultra fast outflow in NGC 2992 at different accretion states". Monthly Notices of the Royal Astronomical Society. 478 (4): 5638–5649. arXiv:1805.12149. Bibcode:2018MNRAS.478.5638M. doi:10.1093/mnras/sty1436.
  3. ^ "NASA/IPAC Extragalactic Database". Results for NGC 0450. Retrieved 2017-05-25.
  4. ^ a b Lianou, S.; et al. (November 2019). "Dust properties and star formation of approximately a thousand local galaxies". Astronomy & Astrophysics. 631: 19. arXiv:1906.02712. Bibcode:2019A&A...631A..38L. doi:10.1051/0004-6361/201834553. S2CID 174801441. A38.
  5. ^ a b c d "NGC/IC Project Restoration Effort". NGC2992. Archived from the original on 2017-12-24. Retrieved 2017-05-25.
  6. ^ a b c Paturel, G.; et al. (December 2003). "HYPERLEDA. I. Identification and designation of galaxies" (PDF). Astronomy and Astrophysics. 412: 45–55. Bibcode:2003A&A...412...45P. doi:10.1051/0004-6361:20031411.
  7. ^ "NGC 2992". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-05-25.
  8. ^ a b c Gilli, R.; et al. (March 2000). "The variability of the Seyfert galaxy NGC 2992: the case for a revived AGN". Astronomy and Astrophysics. 355: 485–498. arXiv:astro-ph/0001107. Bibcode:2000A&A...355..485G.
  9. ^ Veilleux, S.; et al. (January 2001). "The Biconical Outflow in the Seyfert Galaxy NGC 2992". The Astronomical Journal. 121 (1): 198–209. arXiv:astro-ph/0010134. Bibcode:2001AJ....121..198V. doi:10.1086/318046. S2CID 18893501.
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