The Eskimo Nebula (NGC 2392), also known as the Clown-faced Nebula, Lion Nebula, or Caldwell 39, is a bipolar double-shell 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.

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." 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), NASA/IPAC Extragalactic Database (NED), 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.

See also

• List of planetary nebulae
• New General Catalogue