The Eskimo Nebula (NGC 2392), also known as the Clown-faced 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.
Emission nebula | |
---|---|
Planetary nebula | |
![]() NGC 2392, the Eskimo Nebula by HST in 1999. | |
Observation data: J2000 epoch | |
Right ascension | 07h 29m 10.7669s[1] |
Declination | +20° 54′ 42.488″[1] |
Distance | 6520±560[2] ly |
Apparent magnitude (V) | 10.1[1] |
Apparent dimensions (V) | 48″; × 48″;[3] |
Constellation | Gemini |
Physical characteristics | |
Radius | ≥0.34 ly[a] ly |
Absolute magnitude (V) | ≤0.4[b] |
Notable features | – |
Designations | NGC 2392,[1] Caldwell 39, PN G197.8+17.3 Central Star: HIP 36369, HD 59088, TYC 1372-1287-1 |
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
![](http://upload.wikimedia.org/wikipedia/commons/thumb/c/cd/NGC_2392%2C_Eskimo_Nebula.jpg/220px-NGC_2392%2C_Eskimo_Nebula.jpg)
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 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
References
External links
![](http://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png)
- 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