NGC 1667

In today's world, NGC 1667 (title of article) has become a topic of great relevance and interest to a wide variety of people. From its impact on society to its implications in everyday life, NGC 1667 has captured the attention of academics, professionals and citizens in general. With a multidisciplinary approach, this article will address various perspectives on NGC 1667, examining its influence in areas such as technology, culture, economics and politics. In addition, current trends related to NGC 1667 will be analyzed, as well as its possible future projections. Through this exhaustive analysis, we seek to provide a comprehensive view of NGC 1667 and its importance in the contemporary world.

NGC 1667
NGC 1667 by the Hubble Space Telescope
Observation data (J2000 epoch)
ConstellationEridanus
Right ascension04h 48m 37.1976s[1]
Declination−06° 19′ 12.108″[1]
Redshift0.015257 ± 0.000012 [1]
Heliocentric radial velocity4,574 ± 4 km/s[1]
Distance148 ± 57 Mly (45.4 ± 17.4 Mpc)[1]
Apparent magnitude (V)12.1 [2]
Characteristics
TypeSAB(r)c [1]
Size~80,000 ly (24.6 kpc) (estimated)[1]
Apparent size (V)1.8′ × 1.4′[1]
Notable featuresSeyfert Galaxy
Other designations
IRAS 04461-0624, NGC 1689, MCG -01-13-013, PGC 16062[1]

NGC 1667, also catalogued as NGC 1689, is a spiral galaxy located in the constellation Eridanus. It is located at a distance of about 150 million light years from Earth based on redshift-independent methods, which, given its apparent dimensions, means that NGC 1667 is about 80,000 light years across.[1] Based on its redshift, the galaxy sits roughly 200 million light years away from the Sun.[1] It was discovered by Édouard Stephan on December 13, 1884, and independently by Lewis Swift on October 22, 1886.[3]

Characteristics

The galaxy has a small, bright nucleus with a weak bar.[4] There is dust in the inner region of the galaxy, forming a nuclear spiral. Multiple spiral arms are visible near the nucleus, with are roughly symmetrical but the centre of symmetry is offset from the nucleus.[5] The galaxy has an inner ring with many knots measuring 0.33 by 0.24 arcminutes.[4] The ring is composed of many spiral fragments and young star clusters.[6] Three spiral arms emerge from the ring.[7] Many HII regions are visible across the arms and the inner ring.[8] The star formation rate of the galaxy is estimated to be 6.91 M☉ per year.[9]

Active nucleus

The nucleus of the galaxy has been found to be active and it has been characterised as a type 2 Seyfert galaxy based on its emission lines.[10] 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 1667 is estimated to be 107.8 (60 million) M☉.[11]

Although the nucleus emits ultraviolet, radio waves and H-alpha, it isn't a strong source when compared with the rest of the galaxy.[12] The nucleus accounts for about 5% of the H-alpha emission of the galaxy.[8] The nucleus is surrounded by extended HII regions, with signs of photoionization by hot OB stars, indicative of high star formation rate in central region of the galaxy. There are also large amounts of dust.[13] The nucleus also emited mostly soft X-rays at a low flux and with little short-term variability in 2004, but with a significant long-term drop in flux between 1977–78 and 2004.[14]

In the centre of the galaxy there are two peaks of CO(2-1) emission, two arcseconds across. The western peak lies at the kinematic centre of the galaxy. The inner two arcseconds of the galaxy are rotating at an angle of 150° with respect to the rest of the galaxy, indicating its core is counter-rotating, probably as a result of a merger or gas inflows.[15]

The spectrographic study of the nuclear region revealed a nuclear outflow and a gas disk which is twisted by the outflow in the inner arcsecond and gas inflowing from the spiral appear farther from the nucleus. The ionized gas mass outflow rate is estimated to be about 0.16 M☉ per year, while the gas inflow is about 2.8 M☉ per year about 800 parsec from the nucleus. However, most of the inflowing gas will probably not reach the nucleus and accumulate around it, leading to circumnuclear star formation.[16]

Supernova

One supernova has been observed in NGC 1667, SN 1986N. It was discovered on 11 December 1986, with an apparent magnitude of 15, by Carlton R. Pennypacker and others at the Leuschner Observatory. It was located 15" west and 7" south of the centre of the galaxy.[17] Based on its spectrum it was categorised as a type Ia supernova about 20 days post maximum light.[18]

Nearby galaxies

NGC 1667 is a member of the NGC 1667 Group, also known as LGG 118. Other members of the group includes the galaxies IC 387, NGC 1645, NGC 1659, MCG -1-13-12, IC 2101, and IC 2097.[19] NGC 1667 forms a non-interacting pair with NGC 1666, which lies 15 arcminutes away.[4]

References

  1. ^ a b c d e f g h i j k "NASA/IPAC Extragalactic Database". Results for NGC 1667. Retrieved 2016-01-18.
  2. ^ "Revised NGC Data for NGC 1667". spider.seds.org. Retrieved 30 March 2024.
  3. ^ Seligman, Courtney. "NGC 1667 (= PGC 16062)". Celestial Atlas. Retrieved 19 November 2018.
  4. ^ a b c de Vaucouleurs, Gerard Henri; de Vaucouleurs, Antoinette; Shapley, Harlow (1964). Reference catalogue of bright galaxies. Austin: University of Texas Press. Bibcode:1964rcbg.book.....D.
  5. ^ Regan, Michael W.; Mulchaey, John S. (June 1999). "Using HUBBLE SPACE TELESCOPE Imaging of Nuclear Dust Morphology to Rule Out Bars Fueling Seyfert Nuclei". The Astronomical Journal. 117 (6): 2676–2694. doi:10.1086/300888.
  6. ^ Martini, Paul; Regan, Michael W.; Mulchaey, John S.; Pogge, Richard W. (June 2003). "Circumnuclear Dust in Nearby Active and Inactive Galaxies. I. Data". The Astrophysical Journal Supplement Series. 146 (2): 353–406. arXiv:astro-ph/0212396. Bibcode:2003ApJS..146..353M. doi:10.1086/367817.
  7. ^ Sandage, A., Bedke, J. (1994), The Carnegie Atlas of Galaxies. Volume I, Carnegie Institution of Washington
  8. ^ a b Gonzalez Delgado, Rosa M.; Perez, Enrique; Tadhunter, Clive; Vilchez, Jose M.; Rodriguez-Espinosa, Jose Miguel (January 1997). "H ii Region Population in a Sample of Nearby Galaxies with Nuclear Activity. I. Data and General Results". The Astrophysical Journal Supplement Series. 108 (1): 155–198. Bibcode:1997ApJS..108..155G. doi:10.1086/312951.
  9. ^ Theios, Rachel L.; Malkan, Matthew A.; Ross, Nathaniel R. (1 May 2016). "Hα IMAGING OF NEARBY SEYFERT HOST GALAXIES". The Astrophysical Journal. 822 (1): 45. arXiv:1604.00089. Bibcode:2016ApJ...822...45T. doi:10.3847/0004-637X/822/1/45.
  10. ^ Ho, Luis C.; Filippenko, Alexei V.; Sargent, Wallace L. W. (October 1997). "A Search for Dwarf Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies". The Astrophysical Journal Supplement Series. 112 (2): 315–390. arXiv:astro-ph/9704107. Bibcode:1997ApJS..112..315H. doi:10.1086/313041.
  11. ^ Polack, Garrett E.; Revalski, Mitchell; Crenshaw, D. Michael; Fischer, Travis C.; Schmitt, Henrique R.; Kraemer, Steven B.; Meena, Beena; Rafelski, Marc (1 November 2024). "Determining the Extents, Geometries, and Kinematics of Narrow-line Region Outflows in Nearby Seyfert Galaxies". The Astrophysical Journal. 975 (1): 129. arXiv:2407.17550. Bibcode:2024ApJ...975..129P. doi:10.3847/1538-4357/ad71c3.
  12. ^ Schmitt, H. R.; Calzetti, D.; Armus, L.; Giavalisco, M.; Heckman, T. M.; Kennicutt, Jr., R. C.; Leitherer, C.; Meurer, G. R. (May 2006). "Multiwavelength Star Formation Indicators: Observations". The Astrophysical Journal Supplement Series. 164 (1): 52–80. arXiv:astro-ph/0602063. Bibcode:2006ApJS..164...52S. doi:10.1086/501529.
  13. ^ Radovich, M.; Rafanelli, P. (1 February 1996). "Spectroscopy of circumnuclear and extranuclear emission line regions in Seyfert galaxies. I. NGC 1667". Astronomy and Astrophysics. 306: 97. Bibcode:1996A&A...306...97R. ISSN 0004-6361.
  14. ^ Bianchi, S.; Guainazzi, M.; Matt, G.; Chiaberge, M.; Iwasawa, K.; Fiore, F.; Maiolino, R. (October 2005). "A search for changing-look AGN in the Grossan catalog". Astronomy & Astrophysics. 442 (1): 185–194. arXiv:astro-ph/0507323. Bibcode:2005A&A...442..185B. doi:10.1051/0004-6361:20053389.
  15. ^ Ramakrishnan, V; Nagar, N M; Finlez, C; Storchi-Bergmann, T; Slater, R; Schnorr-Müller, A; Riffel, R A; Mundell, C G; Robinson, A (21 July 2019). "Nuclear kinematics in nearby AGN – I. An ALMA perspective on the morphology and kinematics of the molecular CO(2–1) emission". Monthly Notices of the Royal Astronomical Society. 487 (1): 444–455. arXiv:1905.00994. doi:10.1093/mnras/stz1244.
  16. ^ Schnorr-Müller, Allan; Storchi-Bergmann, Thaisa; Ferrari, Fabricio; Nagar, Neil M. (7 January 2017). "Gas inflows towards the nucleus of the Seyfert 2 galaxy NGC 1667". Monthly Notices of the Royal Astronomical Society: stx018. arXiv:1701.00865. doi:10.1093/mnras/stx018.
  17. ^ Pennypacker, C.; Burns, S.; Crawford, F.; Friedman, P.; Graham, J.; Kare, J.; Muller, R.; Okada, C.; Perlmutter, S.; Smith, C.; Treffers, R.; Williams, R.; Aannestad, P.; Stauffer, J. (23 December 1986). "Supernova 1986N in NGC 1667". International Astronomical Union Circular (4287): 1. ISSN 0081-0304.
  18. ^ Filippenko, A. V.; Shields, J. C.; Wheeler, J. C.; Harkness, R. P.; McNaught, R. H. (30 December 1986). "Supernovae". International Astronomical Union Circular (4288): 1. ISSN 0081-0304.
  19. ^ Garcia, A. M. (1 July 1993). "General study of group membership. II. Determination of nearby groups". Astronomy and Astrophysics Supplement Series. 100: 47–90. Bibcode:1993A&AS..100...47G. ISSN 0365-0138.
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