Discovered by William Herschel in 1787 .

NGC 2392 is a classic planetary nebula with a 10.5 magnitude central star.  It is also known as the Eskimo Nebula.  It received the name from its appearance in ground-based photographs where the central "bubble" looks like a face surrounded by a parka.  This remarkable celestial object is a relatively small that subtends a mere 20 arc-seconds.  It is located approximately 4 to 5 thousand light years distant in the northern constellation Gemini.  The nebula's age is estimated to be only about 10,000 years old.

The central star, HD 59088, is a large, dying, star that is a suspected variable.  This star has been the subject of considerable research.  The Space based Chandra Telescope has observed unusual amounts of x-ray emissions associated with the star.  The source of this radiation is still in question, however, it is speculated the central star has a binary stellar partner that is responsible for the observed x-rays.

Detail can be seen in larger instruments when the seeing is good.  The faint outer ring with embedded brighter areas is thought to be the surrounding gas and dust ejected from the dying star during its Red Giant phase.  The central bright oval surrounding the dying central star is composed of the star's outer layers expelled as it contracts to its final white dwarf status.

¹http://chandra.harvard.edu/photo/2013/ngc2392/