NGC 1140

NGC 1140 is an irregular galaxy in the southern constellation of Eridanus. Estimates made using the Tully–Fisher method put the galaxy at about 59 million light years (18 megaparsecs).[2] It was discovered on 22 November 1786 by William Herschel, and was described as "pretty bright, small, round, stellar" by John Louis Emil Dreyer, the compiler of the New General Catalogue.[4]

NGC 1140
NGC 1140, imaged by Hubble
Observation data (J2000 epoch)
ConstellationEridanus
Right ascension02h 54m 33.542s[1]
Declination−10° 01′ 42.60″[1]
Redshift0.005007[2]
Helio radial velocity1150 km/s[2]
Distance59.47 ± 4.18 Mly (18.233 ± 1.283 Mpc)[2]
Apparent magnitude (V)12.25[2]
Apparent magnitude (B)12.84[3]
Absolute magnitude (V)−19.05[2]
Characteristics
TypeIBm pec[2]
Apparent size (V)1.7′ × 0.9′[2]
Notable featuresWolf–Rayet galaxy
Other designations
Markarian 1063, VV 482, MCG-02-08-019, PGC 10966[3]

NGC 1140 is a starburst galaxy, meaning it is forming stars at a very fast rate. In fact, while it is only a tenth as wide as the Milky Way, it is producing stars at a rate of 0.65 M☉/yr,[5] about the same as the Milky Way. The image taken by the Hubble Space Telescope shows bright blue and red regions of star formation, similar to NGC 1569.[6] The starburst is estimated to have begun about 5 million years ago.[5] Its low metallicity (the ratio of hydrogen and helium to other elements) makes NGC 1140 similar to primordial galaxies.[6]

Wolf–Rayet stars, a class of blue, massive, and luminous stars, are present in this galaxy; in fact, NGC 1140 has so many of them that their spectra also appear in the galaxy's spectrum.[5] These types of galaxies are known Wolf–Rayet galaxies, and are fairly rare because Wolf–Rayet stars have short lives.[7]

  • NGC 1140 by GALEX
  • DSS image of NGC 1140

References
  1. Cutri, R. M. (2003). "2MASS All-Sky Catalog of Point Sources". VizieR On-line Data Catalog. Bibcode:2003yCat.2246....0C.
  2. "NED results for object NGC 1140". National Aeronautics and Space Administration / Infrared Processing and Analysis Center. Retrieved 4 March 2017.
  3. "NGC 1140". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 4 March 2017.
  4. Seligman, Courtney. "New General Catalogue objects: NGC 1100 - 1149". cseligman.com. Retrieved 4 March 2017.
  5. Karthick, M. Chrisphin; López-Sánchez, Ángel R.; Sahu, D. K.; Sanwal, B. B.; Bisht, Shuchi (2014). "Photometric and spectroscopic studies of star-forming regions within Wolf-Rayet galaxies". Monthly Notices of the Royal Astronomical Society. 439 (1): 157–178. arXiv:1311.7504. Bibcode:2014MNRAS.439..157K. doi:10.1093/mnras/stt2301.
  6. "A galactic nursery | ESA/Hubble". www.spacetelescope.org. 2015. Retrieved 4 March 2017.
  7. "Intense and short-lived | ESA/Hubble". www.spacetelescope.org. 2015. Retrieved 4 March 2017.
  • Media related to NGC 1140 at Wikimedia Commons


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