NGC 2392 (also the Eskimo Nebula, Caldwell 39, GC 1532, PK 197 +17.1) is a magnitude +9.1 planetary nebula located ~3,830 light years away in the constellation Gemini. The central star, HD 59088, has an observational magnitude of +10.5, and spectral type O8e.
The nebula was discovered by German-British astronomer William Herschel using a 47.5 cm (18.7 inch) f/13 speculum reflector at Windsor Road, Slough, on the 17th January 1787.
The best time for observation is between the months of December and May, preferably from a locality situated in the northern hemisphere, although it generally still visible from all populated areas of the Earth without difficulty, due to its location very close to the ecliptic.
Right Ascension 07h 29m 10.8s, Declination +20° 54' 45"
William Herschel described it as "A star 9th magnitude with a pretty bright middle, nebulosity equally dispersed all around. A very remarkable phenomenon". Read more
Title: [Fe III] emission lines in the planetary nebula NGC 2392 Authors: Y. Zhang, X. Fang, W. Chau, C.-H. Hsia, X.-W. Liu, S. Kwok, N. Koning
NGC 2392 is a young double-shell planetary nebula (PN). Its intrinsic structure and shaping mechanism are still not fully understood. In this paper we present new spectroscopic observations of NGC 2392. The slits were placed at two different locations to obtain the spectra of the inner and outer regions. Several [Fe III] lines are clearly detected in the inner region. We infer that NGC 2392 might have an intrinsic structure similar to the bipolar nebula Mz 3, which also exhibits a number of [Fe III}] lines arising from the central regions. In this scenario, the inner and outer regions of NGC 2392 correspond to the inner lobes and the outer outflows of Mz 3, respectively. We construct a three-dimensional morpho-kinematic model to examine our hypothesis. We also compare the physical conditions and chemical composition of the inner and outer regions, and discuss the implications on the formation of this type of PN.
We recently looked at Castor, the second brightest star in Gemini and a fine multiple star. Not far away, you'll find the remnants of a dying star, the beautiful planetary nebula NGC 2392. This is one of the youngest-known planetary nebula - only 1,000 years old - and it's easily visible in a small telescope, even in city skies. In photographs, this nebula looks a bit like a clown's face; it also resembles the hooded face of a person wearing a parka, so it's sometimes called the "Eskimo Nebula" Read more