Jump to content

Markarian 590

From Wikipedia, the free encyclopedia
(Redirected from NGC 866)
Markarian 590
NGC 863 by SDSS
Observation data (J2000 epoch)
ConstellationCetus
Right ascension02h 14m 33.6s[1]
Declination−00° 46′ 00″[1]
Redshift0.026385 ± 0.000040 [1]
Heliocentric radial velocity7,910 ± 10 km/s[1]
Distance297 ± 19 Mly (91.1 ± 5.7 Mpc)[1]
Apparent magnitude (V)13.2
Characteristics
TypeSA(s)a [1]
Apparent size (V)1.1′ × 1.0′[1]
Notable featuresSeyfert galaxy
Other designations
NGC 863, NGC 866, NGC 885, UGC 1727, MCG +00-06-056, PGC 8586[1]

Markarian 590, also known as NGC 863, NGC 866, and NGC 885, is a spiral galaxy located in the constellation Cetus. It is located at a distance of about 300 million light years from Earth, which, given its apparent dimensions, means that NGC 863 is about 110,000 light years across.[1] It is a change looking Seyfert galaxy.

Observational history

[edit]

Markarian 590 was discovered by William Herschel on January 6, 1785. The galaxy was also discovered independently by Lewis Swift on 3 October 1886, while he also catalogued it again as a different galaxy on 31 October 1886, and thus the galaxy is listed three times in the New General Catalogue. John Louis Emil Dreyer described it as very faint, round, brighter middle, stellar.[2]

One supernova has been observed in Markarian 590, SN 2018djd. SN 2018djd is a type Ia supernova[3] discovered by All Sky Automated Survey for SuperNovae (ASAS-SN) on 12 July 2018. The supernova was detected in images obtained on 10.61 July 2018, when it had a magnitude of 16.5.[4] It reached a maximum apparent magnitude of 15.4.[5]

Characteristics

[edit]
The central region of Markarian 590 by the Hubble Space Telescope.

The nucleus of Markarian 590 has been found to be active. The most accepted theory for the energy source of active galactic nuclei is the presence of an accretion disk around a supermassive black hole. The mass of the black hole in the centre of NGC 4593 is estimated to be (47.5±7.4)×106 M☉ based on reverberation mapping.[6]

The active galactic nucleus (AGN) of Markarian 590 has been categorised as change looking.[7] This category of Seyfert galaxies is characterised by a change in the spectrum, with the broad emission lines disappearing or appearing, and thus changing the galaxy from to type I to type II and vice versa.[8] Markarian 590 was originally characterised as a type I Seyfert galaxy, but later observations categorised the galaxy as type 1.5[9] and type 1.9-2.[8]

The broad line emission of Markarian 590 strengthened by a factor of tens from the 1970s to the 1990s and then decreased about 100 times in the 2000s in optical, UV, and X-ray wavelengths, and the broad component of the Hβ emission line disappeared completely.[8] Observations by Suzaku X-ray satellite in 2011 revealed that the soft X-ray excess emission could no longer be detected, while the X-ray continuum flux had minimal change.[10] The X-ray spectrum doesn't show evidence of obstruction;[8] instead the variation is caused by a change in accretion rate.[11] Observations of the galaxy in the infrared wavelengths revealed a sharp decrease in luminosity between 2000 and 2001. Also, during the low activity period, the radius of the circumnuclear dust torus decreased to 32 light days.[12] In 2014, the soft excess emission had reappeared in observations by Chandra X-ray Observatory, as well as the broad MgII emission line.[7]

The radio emission of the galaxy is concentrated to a single core source, and extends to two components at a radius of about 2 arcsec (~1 kpc) and 6 arcsec (~3 kpc) from the core, that probably are related to the ring-like molecular gas structures observed in CO(3-2) imaging.[11] The outer gas ring is probably related to the spiral arms of the galaxy while the inner ring is related to faint dust lanes. The central molecular gas mass is estimated to be less than 1.6×105 M☉, not significantly less than other AGNs.[13] A faint parsec-scale radio jet extending 2.8 mas to the north has been detected using very-long-baseline interferometry.[14] The radio emission exhibits long term variation that follows that of the other wavelengths.[11]

X-ray observations of the galaxy has shown the presence of ultra fast outflows, in the form of blueshifted absorption lines of O viii, Ne ix, Si xiv, and Mg xii.[15]

References

[edit]
  1. ^ a b c d e f g h i "NASA/IPAC Extragalactic Database". Results for NGC 863. Retrieved 2023-05-06.
  2. ^ Seligman, Courtney. "NGC 863". Celestial Atlas. Retrieved 19 November 2018.
  3. ^ "ATel #11864: Spectroscopic classification of 12 transients with du Pont". The Astronomer's Telegram. 17 July 2018. Retrieved 17 June 2023.
  4. ^ "ATel #11848: ASASSN-18pb: Discovery of A Probable Supernova in Seyfert 1 AGN host Mrk 590". The Astronomer's Telegram. 13 July 2018. Retrieved 17 June 2023.
  5. ^ "Bright Supernovae - 2018". www.rochesterastronomy.org. Retrieved 17 June 2023.
  6. ^ Peterson, B. M.; Ferrarese, L.; Gilbert, K. M.; Kaspi, S.; Malkan, M. A.; Maoz, D.; Merritt, D.; Netzer, H.; Onken, C. A.; Pogge, R. W.; Vestergaard, M.; Wandel, A. (October 2004). "Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation-Mapping Database". The Astrophysical Journal. 613 (2): 682–699. arXiv:astro-ph/0407299. Bibcode:2004ApJ...613..682P. doi:10.1086/423269. hdl:1885/33814. S2CID 16308360.
  7. ^ a b Mathur, S.; Denney, K. D.; Gupta, A.; Vestergaard, M.; De Rosa, G.; Krongold, Yair; Nicastro, F.; Collinson, J.; Goad, M.; Korista, K.; Pogge, R. W.; Peterson, B. M. (18 October 2018). "The Changing-look Quasar Mrk 590 Is Awakening". The Astrophysical Journal. 866 (2): 123. arXiv:1810.06616. Bibcode:2018ApJ...866..123M. doi:10.3847/1538-4357/aadd91. hdl:2381/45545.
  8. ^ a b c d Denney, K. D.; De Rosa, G.; Croxall, K.; Gupta, A.; Bentz, M. C.; Fausnaugh, M. M.; Grier, C. J.; Martini, P.; Mathur, S.; Peterson, B. M.; Pogge, R. W.; Shappee, B. J. (17 November 2014). "THE TYPECASTING OF ACTIVE GALACTIC NUCLEI: Mrk 590 NO LONGER FITS THE ROLE". The Astrophysical Journal. 796 (2): 134. arXiv:1404.4879. Bibcode:2014ApJ...796..134D. doi:10.1088/0004-637X/796/2/134. S2CID 119742660.
  9. ^ Osterbrock, D. E. (August 1977). "Spectrophotometry of Seyfert 1 galaxies". The Astrophysical Journal. 215: 733. Bibcode:1977ApJ...215..733O. doi:10.1086/155407.
  10. ^ Rivers, Elizabeth; Markowitz, Alex; Duro, Refiz; Rothschild, Richard (1 November 2012). "A SUZAKU OBSERVATION OF Mkn 590 REVEALS A VANISHING SOFT EXCESS". The Astrophysical Journal. 759 (1): 63. arXiv:1210.3330. Bibcode:2012ApJ...759...63R. doi:10.1088/0004-637X/759/1/63. S2CID 118423911.
  11. ^ a b c Koay, J. Y.; Vestergaard, M.; Bignall, H. E.; Reynolds, C.; Peterson, B. M. (21 July 2016). "Parsec-scale radio morphology and variability of a changing-look AGN: the case of Mrk 590". Monthly Notices of the Royal Astronomical Society. 460 (1): 304–316. doi:10.1093/mnras/stw975. hdl:10150/621462.
  12. ^ Kokubo, Mitsuru; Minezaki, Takeo (1 February 2020). "Rapid luminosity decline and subsequent reformation of the innermost dust distribution in the changing-look AGN Mrk 590". Monthly Notices of the Royal Astronomical Society. 491 (4): 4615–4633. arXiv:1904.08946. doi:10.1093/mnras/stz3397.
  13. ^ Koay, J. Y.; Vestergaard, M.; Casasola, V.; Lawther, D.; Peterson, B. M. (21 January 2016). "ALMA probes the molecular gas reservoirs in the changing-look Seyfert galaxy Mrk 590". Monthly Notices of the Royal Astronomical Society. 455 (3): 2745–2764. arXiv:1509.09203. doi:10.1093/mnras/stv2495.
  14. ^ Yang, Jun; van Bemmel, Ilse; Paragi, Zsolt; Komossa, S; Yuan, Feng; Yang, Xiaolong; An, Tao; Koay, J Y; Reynolds, C; Oonk, J B R; Liu, Xiang; Wu, Qingwen (28 January 2021). "A parsec-scale faint jet in the nearby changing-look Seyfert galaxy Mrk 590". Monthly Notices of the Royal Astronomical Society: Letters. 502 (1): L61–L65. arXiv:2101.04629. doi:10.1093/mnrasl/slab005.
  15. ^ Gupta, A.; Mathur, S.; Krongold, Y. (9 December 2014). "DETECTION OF HIGH VELOCITY OUTFLOWS IN THE SEYFERT 1 GALAXY Mrk 590". The Astrophysical Journal. 798 (1): 4. arXiv:1406.5968. doi:10.1088/0004-637X/798/1/4. S2CID 119028585.
[edit]
Wikimedia Commons has media related to NGC 863.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Markarian_590&oldid=1241160379"