NGC 3995

NGC 3995
NGC 3995 by Sloan Digital Sky Survey
Observation data (J2000 epoch)
ConstellationUrsa Major
Right ascension11h 57m 44.1s[1]
Declination+32° 17′ 39″[1]
Redshift0.010938 ± 0.000002 [1]
Heliocentric radial velocity3,279 ± 1 km/s[1]
Distance102 Mly (31.2 Mpc)[1]
Apparent magnitude (V)12.1[2]
Characteristics
TypeSAm pec [1]
Apparent size (V)1.89′ × 0.78′[1]
Notable featuresInteracting galaxy
Other designations
UGC 6944, Arp 313, VV 249a, MCG +06-26-061, PGC 37624, HOLM 309A

NGC 3995 is a Magellanic spiral galaxy in the constellation Ursa Major. The galaxy lies about 100 million light years away from Earth based on the Tully–Fisher relation, which means, given its apparent dimensions, that NGC 3995 is approximately 80,000 light years across, while based on redshift it lies 170 million light years away.[1] It was discovered by Heinrich d'Arrest on February 5, 1864.[3]

NGC 3995 forms a triplet of galaxies with NGC 3994, which lies 1.9 arcminutes, and NGC 3991, which lies 3.7 arcminutes away. The triplet has been included in Halton Arp's Atlas of Peculiar Galaxies as Arp 313. Both NGC 3995 and NGC 3991 have disturbed appearances while NGC 3994 does not.[4] The triplet is part of the NGC 3966 Group or LGG 259. Other members include NGC 3966, NGC 3935, NGC 3986, IC 2973, UGC 6892, IC 2978, and IC 2979.[5][6]

The star formation rate of NGC 3995 is estimated to be 4.2±0.9 M☉ per year, with higher rates observed near the centre of the galaxy.[7] The nucleus of the galaxy has emission that resembles an HII region.[8] The spectrum of the galaxy has Wolf-Rayet features, indicative of recent star formation.[9] Hubble Space Telescope detected 46 star formation knots in the galaxy, most of them having ages less than 20 million years.[10]

Two supernovae have been observed in NGC 3995, SN 1988ac and SN 2000ez, a type II supernova.[11]

  1. ^ a b c d e f g h "NASA/IPAC Extragalactic Database". Results for NGC 3995. Retrieved 2024-03-26.
  2. ^ "Revised NGC Data for NGC 3995". spider.seds.org. Retrieved 30 March 2024.
  3. ^ Seligman, Courtney. "NGC 3995 (= Arp 24)". Celestial Atlas. Retrieved 19 November 2018.
  4. ^ Sandage, A., Bedke, J. (1994), The Carnegie Atlas of Galaxies. Volume I, Carnegie Institution of Washington
  5. ^ 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.
  6. ^ Makarov, Dmitry; Karachentsev, Igor (21 April 2011). "Galaxy groups and clouds in the local (z~ 0.01) Universe". Monthly Notices of the Royal Astronomical Society. 412 (4): 2498–2520. arXiv:1011.6277. Bibcode:2011MNRAS.412.2498M. doi:10.1111/j.1365-2966.2010.18071.x. S2CID 119194025.
  7. ^ Logroño-García, R.; Vilella-Rojo, G.; López-Sanjuan, C.; Varela, J.; Viironen, K.; Muniesa, D. J.; Cenarro, A. J.; Cristóbal-Hornillos, D.; Ederoclite, A.; Marín-Franch, A.; Moles, M.; Vázquez Ramió, H.; Bonoli, S.; Díaz-García, L. A.; Orsi, A.; San Roman, I.; Akras, S.; Chies-Santos, A. L.; Coelho, P. R. T.; Daflon, S.; Costa-Duarte, M. V.; Dupke, R.; Galbany, L.; González Delgado, R. M.; Hernandez-Jimenez, J. A.; Lopes de Oliveira, R.; Mendes de Oliveira, C.; Oteo, I.; Gonçalves, D. R.; Sánchez-Portal, M.; Schmidtobreick, L.; Sodré, L. (February 2019). "J-PLUS: Measuring H α emission line fluxes in the nearby universe". Astronomy & Astrophysics. 622: A180. arXiv:1804.04039. Bibcode:2019A&A...622A.180L. doi:10.1051/0004-6361/201732487.
  8. ^ Kewley, Lisa J.; Rupke, David; Jabran Zahid, H.; Geller, Margaret J.; Barton, Elizabeth J. (20 September 2010). "Metallicity Gradients and Gas Flows in Galaxy Pairs". The Astrophysical Journal. 721 (1): L48–L52. arXiv:1008.2204. Bibcode:2010ApJ...721L..48K. doi:10.1088/2041-8205/721/1/L48.
  9. ^ Schaerer, D.; Contini, T.; Pindao, M. (April 1999). "New catalogue of Wolf-Rayet galaxies and high-excitation extra-galactic Hii regions". Astronomy and Astrophysics Supplement Series. 136 (1): 35–52. arXiv:astro-ph/9812347. Bibcode:1999A&AS..136...35S. doi:10.1051/aas:1999197.
  10. ^ Eggers, D.; Weistrop, D.; Stone, A.; Nelson, C. H.; Hancock, M. (January 2005). "Hubble Space Telescope Observations of Star-forming Regions in NGC 3994/3995". The Astronomical Journal. 129 (1): 136–147. Bibcode:2005AJ....129..136E. doi:10.1086/426358.
  11. ^ "Bright Supernova pages - Most prolific galaxies". www.rochesterastronomy.org. Retrieved 22 April 2024.