Eskimo Nebula

Eskimo Nebula

Eskimo Nebula
NGC 2392, the Eskimo Nebula by HST.
Observation data
(Epoch J2000)
Right ascension 07h 29m 10.7669s[1]
Declination +20° 54′ 42.488″[1]
Distance ≥2,870 ly (≥880 pc)[2]
Apparent magnitude (V) 10.1[1]
Apparent dimensions (V) 48″ × 48″[3]
Constellation Gemini
Physical characteristics
Radius ≥0.34 ly[a]
Absolute magnitude (V) ≤0.4 [b]
Notable features
Other designations NGC 2392,[1] Caldwell 39, Clown Nebula,[1] Clown Face[1]

The Eskimo Nebula (NGC 2392), also known as the Clownface Nebula[4] or Caldwell 39, is a bipolar[2] double-shell[5] 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, Eskimo Nebula in 32 inch telescope

NGC 2392 lies more than 2,870 light-years away and is visible with a small telescope (but more preferably with a larger telescope) in the constellation of Gemini.


  • Historic data 1
  • See also 2
  • Notes 3
  • References 4
  • External links 5

Historic data

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."[6] NGC 2392 WH IV-45 is included in the Astronomical League's Herschel 400 observing program.

See also


  1. ^ Radius = distance × sin(angular size / 2) = ≥2900 ly * sin(48″ / 2) = ≥0.34 ly
  2. ^ 10.1 apparent magnitude - 5 * (log10(≥880 pc distance) - 1) = ≤0.4 absolute magnitude


  1. ^ a b c d e f "SIMBAD Astronomical Database". Results for Eskimo Nebula. Retrieved 2006-12-22. 
  2. ^ a b O'dell, C. R.; Balick, B.; Hajian, A. R.; Henney, W. J.; et al. (2003). "Knots in Planetary Nebulae". Winds, Bubbles, and Explosions: a conference to honor John Dyson, Pátzcuaro, Michoacán, México, September 9–13, 2002 (Eds. S. J. Arthur & W. J. Henney) Revista Mexicana de Astronomía y Astrofísica (Serie de Conferencias) ( 15: 29–33.  
  3. ^ 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.  
  4. ^ Windows to the Universe
  5. ^ 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?".  
  6. ^ The Scientific Papers of Sir William Herschel by J. L. E. Dreyer, Royal Society, London 1912

External links

  • APOD (2003-12-07) – NGC 2392: The Eskimo Nebula
  • The Eskimo Nebula on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images

  • Eskimo Nebula at Constellation Guide