NGC 985

Last updated
NGC 985
NGC985 - SDSS DR14.jpg
NGC 985 by the SDSS
Observation data (J2000 epoch)
Constellation Cetus
Right ascension 02h 34m 37.8s [1]
Declination −08° 47′ 15″ [1]
Redshift 0.043143 ± 0.000073 [1]
Helio radial velocity 12,934 ± 22 km/s [1]
Distance 567 Mly (174 Mpc) [1]
Apparent magnitude  (V)13.5
Characteristics
Type Ring pec [1]
Apparent size  (V)1.0′ × 0.9′ [1]
Notable featuresSeyfert galaxy
Other designations
VV 285, Mrk 1048, MCG -02-07-035, PGC 9817 [1]

NGC 985 is a ring galaxy in the constellation of Cetus. It is located about 550 million light years away from Earth, which means, given its apparent dimensions, that NGC 985 is approximately 160,000 light years across. It was discovered by Francis Leavenworth in 1886. [2] It is a type 1 Seyfert galaxy. [3]

NGC 985 is characterised by its ring shape. It is believed it was formed as a result of a galaxy merger. Further evidence supporting this theory is the observation of a second nucleus in NGC 985. [4] When observed in infrared light, a second nucleus was found 3.8 arcseconds northwest of the active nucleus. It is much redder than the rest of the galaxy, indicating the presence of old stars. It has been suggested that the collision between a disk galaxy with another galaxy caused the formation of the ring and displaced the nucleus of the galaxy, creating an empty ring. Based on the kinematics of the galaxy, the secondary nucleus belonged to the intruder galaxy, while the active nucleus is associated with the main stellar component. [5] [6]

As is common with merger remnants, NGC 985 has increased star formation rate, and as a result shines bright in the infrared. The total infrared luminosity of NGC 985 is 1.8×1011  L☉ and it is characterised as a luminous infrared galaxy. The total molecular gas mass of the galaxy is estimated to be 2×1010  M☉ . Very large molecular clouds exist near the nuclei. They may be clouds gathering around the nucleus in the process of forming a disk around the two nuclei or molecular clouds disrupted by an outflow from the nucleus of the galaxy. [7]

NGC 985 is a powerful X-ray source, detected by ROSAT. It is a complex X-ray source, whose spectrum cannot be accounted for by a simple power law at 0.6 keV and suggests the presence of a warm absorber. [8] The hard X-ray emission on the other hand is characterised by a simple power law. [9] The X-ray flux, especially soft X-rays, diminished in NGC 985 in 2013. The variability of the X-ray and ultraviolet emission from the nucleus was observed using the XMM-Newton and Hubble Space Telescope respectively. These observations revealed the presence of outflowing wind from an accretion disk formed around a supermassive black hole that obstructed the nucleus in soft X-rays and UV. The nucleus is otherwise seen unobstructed. [10]

Related Research Articles

An active galactic nucleus (AGN) is a compact region at the center of a galaxy that has a much-higher-than-normal luminosity over at least some portion of the electromagnetic spectrum with characteristics indicating that the luminosity is not produced by stars. Such excess, non-stellar emissions have been observed in the radio, microwave, infrared, optical, ultra-violet, X-ray and gamma ray wavebands. A galaxy hosting an AGN is called an active galaxy. The non-stellar radiation from an AGN is theorized to result from the accretion of matter by a supermassive black hole at the center of its host galaxy.

<span class="mw-page-title-main">Seyfert galaxy</span> Class of active galaxies with very bright nuclei

Seyfert galaxies are one of the two largest groups of active galaxies, along with quasars. They have quasar-like nuclei with very high surface brightnesses whose spectra reveal strong, high-ionisation emission lines, but unlike quasars, their host galaxies are clearly detectable.

<span class="mw-page-title-main">NGC 5548</span> Type I Seyfert galaxy in the constellation Boötes

NGC 5548 is a Type I Seyfert galaxy with a bright, active nucleus. This activity is caused by matter flowing onto a 65 million solar mass (M☉) supermassive black hole at the core. Morphologically, this is an unbarred lenticular galaxy with tightly-wound spiral arms, while shell and tidal tail features suggest that it has undergone a cosmologically-recent merger or interaction event. NGC 5548 is approximately 245 million light years away and appears in the constellation Boötes. The apparent visual magnitude of NGC 5548 is approximately 13.3 in the V band.

<span class="mw-page-title-main">NGC 7319</span> Galaxy in the constellation Pegasus

NGC 7319 is a highly distorted barred spiral galaxy that is a member of the compact Stephan's Quintet group located in the constellation Pegasus, some 311 megalight-years distant from the Milky Way. The galaxy's arms, dust and gas have been highly disturbed as a result of the interaction with the other members of the Quintet. Nearly all of the neutral hydrogen has been stripped from this galaxy, most likely as a result of a collision with NGC 7320c some 100 million years ago. A pair of long, parallel tidal tails extend southward from NGC 7319 in the direction of NGC 7320c, and is undergoing star formation.

<span class="mw-page-title-main">Ionization cone</span> Astronomical phenomenon

Ionization cones are cones of ionized material extending from active galactic nuclei, predominantly observed in type II Seyfert galaxies. They are detected through their emission of electromagnetic radiation in the visible and infrared parts of the spectrum. The main method of observation is through spectroscopy, using spectral line analysis to measure the shape of the ionized region and the condition of the material such as temperature, density, composition, and degree of ionization.

<span class="mw-page-title-main">NGC 3783</span> Galaxy in the constellation Centaurus

NGC 3783 is a barred spiral galaxy located about 135 million light years away in the constellation Centaurus. It is inclined by an angle of 23° to the line of sight from the Earth along a position angle of about 163°. The morphological classification of SBa indicates a bar structure across the center (B) and tightly-wound spiral arms (a). Although not shown by this classification, observers note the galaxy has a luminous inner ring surrounding the bar structure. The bright compact nucleus is active and categorized as a Seyfert 1 type. This nucleus is a strong source of X-ray emission and undergoes variations in emission across the electromagnetic spectrum.

<span class="mw-page-title-main">NGC 4698</span> Galaxy in the constellation Virgo

NGC 4698 is a barred spiral galaxy located around 55 million light years away from Earth in the constellation of Virgo. It belongs to the Virgo Cluster of galaxies and is positioned near the northeastern edge of this assemblage. The morphological classification of NGC 4698 in the De Vaucouleurs system is SA(s)ab, which indicates a purely spiral structure with moderate to tightly wound arms. It is inclined to the line of sight from the Earth by an angle of 53° along a position angle of 170°.

<span class="mw-page-title-main">NGC 3081</span> Galaxy in the constellation Hydra

NGC 3081 is a barred lenticular ring galaxy in the constellation of Hydra. NGC 3081 is located about 85 million light-years away from Earth, which means, given its apparent dimensions, that NGC 3081 is approximately 60,000 light-years across. It is a type II Seyfert galaxy, characterised by its bright nucleus. It was discovered by William Herschel on 21 December 1786.

<span class="mw-page-title-main">NGC 7469</span> Galaxy located in the constellation Pegasus

NGC 7469 is an intermediate spiral galaxy in the constellation of Pegasus. NGC 7469 is located about 200 million light-years away from Earth, which means, given its apparent dimensions, that NGC 7469 is approximately 90,000 light-years across. It was discovered by William Herschel on November 12, 1784.

<span class="mw-page-title-main">NGC 7130</span> Galaxy in the constellation Piscis Austrinus

NGC 7130 is a spiral galaxy located in the constellation Piscis Austrinus. It is located at a distance of about 220 million light years from Earth, which, given its apparent dimensions, means that NGC 7130 is about 100,000 light years across. It was discovered by John Herschel on September 25, 1834, and discovered independently by Lewis Swift on September 17, 1897. The location of the galaxy given in the New General Catalogue was off by 30 arcminutes in declination from the location of the galaxy.

<span class="mw-page-title-main">NGC 7674</span> Galaxy located in the constellation Pegasus

NGC 7674 is a spiral galaxy located in the constellation Pegasus. It is located at a distance of circa 350 million light years from Earth, which, given its apparent dimensions, means that NGC 7674 is about 125,000 light years across. It was discovered by John Herschel on August 16, 1830.

<span class="mw-page-title-main">NGC 4636</span> Galaxy in the constellation Virgo

NGC 4636 is an elliptical galaxy located in the constellation Virgo. It is a member of the NGC 4753 Group of galaxies, which is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster. It is located at a distance of about 55 million light years from Earth, which, given its apparent dimensions, means that NGC 4636 is about 105,000 light years across.

<span class="mw-page-title-main">NGC 1386</span> Galaxy in the constellation Eridanus

NGC 1386 is a spiral galaxy located in the constellation Eridanus. It is located at a distance of circa 53 million light years from Earth, which, given its apparent dimensions, means that NGC 1386 is about 50,000 light years across. It is a Seyfert galaxy, the only one in Fornax Cluster.

<span class="mw-page-title-main">NGC 2273</span> Galaxy in the constellation Lynx

NGC 2273 is a barred spiral galaxy located in the constellation Lynx. It is located at a distance of circa 95 million light years from Earth, which, given its apparent dimensions, means that NGC 2273 is about 100,000 light years across. It was discovered by Nils Dunér on September 15, 1867.

<span class="mw-page-title-main">NGC 1142</span> Interacting and distorted spiral galaxy in the constellation Cetus

NGC 1142 is a distorted spiral galaxy in the constellation of Cetus. It is located about 370 million light years away from Earth, which means, given its apparent dimensions, that NGC 1142 is approximately 170,000 light years across. It is a type 2 Seyfert galaxy. It interacts with the elliptical galaxy NGC 1141.

<span class="mw-page-title-main">NGC 7592</span> Interacting galaxy system in the constellation Aquarius

NGC 7592 is an interacting galaxy system located 300 million light years away in the constellation Aquarius. It was discovered by William Herschel on September 20, 1784. The total infrared luminosity is 1011.33 L☉, and thus it is categorised as a luminous infrared galaxy. One of the galaxies hosts a type 2 Seyfert nucleus.

<span class="mw-page-title-main">NGC 7679</span> Galaxy in the constellation Pisces

NGC 7679 is a lenticular galaxy with a peculiar morphology in the constellation Pisces. It is located at a distance of circa 200 million light years from Earth, which, given its apparent dimensions, means that NGC 7679 is about 60,000 light years across. It was discovered by Heinrich d'Arrest on September 23, 1864. The total infrared luminosity is 1011.05 L☉, and thus it is categorised as a luminous infrared galaxy. NGC 7679 is both a starburst galaxy and a Seyfert galaxy.

<span class="mw-page-title-main">NGC 2617</span> Galaxy in the constellation Hydra

NGC 2617 is a Seyfert galaxy in the equatorial constellation of Hydra. It was discovered on February 12, 1885, by French astronomer Édouard Stephan. In 1888, Danish astronomer J. L. E. Dreyer described it as "extremely faint, very small, 2 very faint stars involved". It is located at an estimated distance of 202 million light years. In the infrared, the galaxy has an angular size of 0.693 by 0.652 arcminutes.

<span class="mw-page-title-main">UGC 5101</span> Galaxy in the constellation of Ursa Major

UGC 5101 is a galaxy merger located in the constellation Ursa Major. It is located at a distance of about 530 million light years from Earth. It is an ultraluminous infrared galaxy. The total infrared luminosity of the galaxy is estimated to be 1011.95 L☉ and the galaxy has a total star formation rate of 105 M☉ per year.

<span class="mw-page-title-main">NGC 2110</span>

NGC 2110 is a lenticular galaxy located in the constellation Orion. It is located at a distance of about 120 million light years from Earth, which, given its apparent dimensions, means that NGC 2110 is about 90,000 light years across. It was discovered by William Herschel on October 5, 1785. It is a Seyfert galaxy.

References

  1. 1 2 3 4 5 6 7 8 "NASA/IPAC Extragalactic Database". Results for NGC 985. Retrieved 2017-04-18.
  2. ↑ Seligman, Courtney. "NGC 985 (= PGC 9817)". Celestial Atlas. Retrieved 19 November 2018.
  3. ↑ Doi, Akihiro; Inoue, Yoshiyuki (1 August 2016). "High-frequency excess in the radio continuum spectrum of the type-1 Seyfert galaxy NGC 985". Publications of the Astronomical Society of Japan. 68 (4): 56. arXiv: 1605.07518 . Bibcode:2016PASJ...68...56D. doi:10.1093/pasj/psw052. S2CID   119264651.
  4. ↑ Appleton, P. N.; Marcum, P. M. (November 1993). "Infrared Observations of the Seyfert Ring Galaxy NGC 985". The Astrophysical Journal. 417: 90. Bibcode:1993ApJ...417...90A. doi: 10.1086/173293 .
  5. ↑ Garcia, A. M. Perez; Espinosa, J. M. Rodriguez (November 1996). "A Companion Nuclear Bulge to the Seyfert Ring Galaxy NGC 985". The Astronomical Journal. 112: 1863. Bibcode:1996AJ....112.1863P. doi:10.1086/118147.
  6. ↑ Arribas, S.; Mediavilla, E.; del Burgo, C.; Garcia-Lorenzo, B. (February 1999). "Two-dimensional Spectroscopy in the Circumnuclear Region of the Seyfert 1 Ring Galaxy NGC 985". The Astrophysical Journal. 511 (2): 680–685. Bibcode:1999ApJ...511..680A. doi: 10.1086/306706 .
  7. ↑ Appleton, P. N.; Charmandaris, V.; Gao, Yu; Combes, F.; Ghigo, F.; Horellou, C.; Mirabel, I. F. (20 February 2002). "Mid-Infrared and CO Observations of the Infrared/X-Ray Luminous Seyfert 1 Galaxy NGC 985: The Making or Breaking of a ULIRG?". The Astrophysical Journal. 566 (2): 682–698. arXiv: astro-ph/0109448 . Bibcode:2002ApJ...566..682A. doi: 10.1086/338227 .
  8. ↑ Brandt, W. N.; Fabian, A. C.; Nandra, K.; Reynolds, C. S.; Brinkmann, W. (15 December 1994). "ROSAT PSPC observations of the Seyfert 1 galaxies Ark 564, NGC 985, Kaz 163, Mrk 79 and RX J2256.6+0525". Monthly Notices of the Royal Astronomical Society. 271 (4): 958–966. arXiv: astro-ph/9411063 . Bibcode:1994MNRAS.271..958B. doi:10.1093/mnras/271.4.958. S2CID   119066001.
  9. ↑ Risaliti, G.; Gilli, R.; Maiolino, R.; Salvati, M. (1 May 2000). "The hard X-ray emission of luminous infrared galaxies". Astronomy and Astrophysics. 357: 13–23. arXiv: astro-ph/0002460 . Bibcode:2000A&A...357...13R. ISSN   0004-6361.
  10. ↑ Ebrero, J.; Kriss, G. A.; Kaastra, J. S.; Ely, J. C. (27 January 2016). "Discovery of a fast, broad, transient outflow in NGC 985". Astronomy & Astrophysics. 586: A72. arXiv: 1511.07169 . Bibcode:2016A&A...586A..72E. doi:10.1051/0004-6361/201527495. S2CID   119229536.


This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.