Eskimo Nebula
Planetary nebula in the constellation Gemini
The Eskimo Nebula (NGC 2392 ), also known as the Clown Face Nebula , Lion Nebula ,[ 4] or Caldwell 39 , is a bipolar [ 5] double-shell[ 6] planetary nebula (PN). It was discovered by astronomer William Herschel in 1787. The formation resembles a person's head surrounded by a parka hood. It is surrounded by gas that composed the outer layers of a Sun-like star . The visible inner filaments are ejected by a strong wind of particles from the central star. The outer disk contains unusual, light-year-long filaments.
NGC 2392 lies about 6500 light-years away, and is visible with a small telescope in the constellation of Gemini .
At the center of NGC 2392, there is an O-type star with a spectral type of O(H)6f.[ 7]
Historic data
NGC 2392 in 32 inch telescope
The nebula was discovered by William Herschel on January 17, 1787, in Slough , England. He described it as "A star 9th magnitude with a pretty bright middle, nebulosity equally dispersed all around. A very remarkable phenomenon."[ 8] NGC 2392 WH IV-45 is included in the Astronomical League 's Herschel 400 observing program.
Location
NGC 2392 is located just east of δ Geminorum , just south of the ecliptic .
Naming controversy
On 11 August 2020, the IAU Working Group on Star Names (WGSN),[citation needed ] NASA/IPAC Extragalactic Database (NED),[citation needed ] and SIMBAD Astronomical Database (CDS) discontinued use of three nicknames that were perceived as offensive - "Eskimo Nebula", "Clown Face Nebula", and "Clownface Nebula" - and strongly recommended the nebula be referred to by its NGC designation in further publications.[ 9] [ 1]
See also
Notes
^ Radius = distance × sin(angular size / 2) = ≥2900 ly * sin(48″ / 2) = ≥0.34 ly
^ 10.1 apparent magnitude - 5 * (log10 (≥880 pc distance) - 1) = ≤0.4 absolute magnitude
References
^ a b c d e "NGC 2392" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2006-12-22 .
^ Gaia Collaboration et al. (2018b): Summary of the contents and survey properties
^ O'Dell, C. R.; Balick, B.; Hajian, A. R.; Henney, W. J.; et al. (2002). "Knots in Nearby Planetary Nebulae" . The Astronomical Journal . 123 (6): 3329–3347. Bibcode :2002AJ....123.3329O . doi :10.1086/340726 .
^ Deep-Sky Companions: The Caldwell Objects, 2nd Edition, Stephen James O'Meara, 2016, p.181
^ O'dell, C. R.; Balick, B.; Hajian, A. R.; Henney, W. J.; et al. (2003). "Knots in Planetary Nebulae" . In S. J. Arthur & W. J. Henney (ed.). Revista Mexicana de Astronomía y Astrofísica (Serie de Conferencias) . Winds, Bubbles, and Explosions: a conference to honor John Dyson, Pátzcuaro, Michoacán, México, September 9–13, 2002. Vol. 15. pp. 29–33. Bibcode :2003RMxAC..15...29O . Archived from the original on 2018-05-01. Retrieved 2007-01-04 .
^ Guerrero, M. A.; Chu, Y.-H.; Gruendl, R. A.; Meixner, M. (2005). "XMM-Newton detection of hot gas in the Eskimo Nebula: Shocked stellar wind or collimated outflows?". Astronomy and Astrophysics . 430 (3): L69–L72. arXiv :astro-ph/0412540 . Bibcode :2005A&A...430L..69G . doi :10.1051/0004-6361:200400131 . S2CID 6518963 .
^ González-Santamaría, I.; Manteiga, M.; Manchado, A.; Ulla, A.; Dafonte, C.; López Varela, P. (2021). "Planetary nebulae in Gaia EDR3: Central star identification, properties, and binarity". Astronomy & Astrophysics . 656 : A51. arXiv :2109.12114 . Bibcode :2021A&A...656A..51G . doi :10.1051/0004-6361/202141916 . S2CID 237940344 .
^ The Scientific Papers of Sir William Herschel by J. L. E. Dreyer , Royal Society, London 1912
^ Talbert, Tricia (11 August 2020). "NASA to Reexamine Nicknames for Cosmic Objects" . NASA . Retrieved 11 August 2020 .
External links
Wikimedia Commons has media related to
NGC 2392 .
NGC 2392 on WikiSky : DSS2 , SDSS , GALEX , IRAS , Hydrogen α , X-Ray , Astrophoto , Sky Map , Articles and images
APOD (2003-12-07) – NGC 2392
Eskimo Nebula Lowell Observatory
The Structure & Evolution of the Eskimo Planetary Nebula University of Maryland Astronomy Department
A Kinematic Determination of the Structure of the Double Ring Planetary Nebula NGC 2392, the Eskimo Astrophysical Journal v.362, p. 226 October 1990
A Cat's Eye view of the Eskimo from Saturn Maria-Teresa Garc ́ıa-D ́ıaz, Jose-Alberto L ́opez, Wofgang Steffen, Michael G. Richer and Hortensia Riesgo, 2011