IPHASX J205013.6+465515, informally known as the Ear Nebula, is a faint bipolarplanetary nebula located in the constellation of Cygnus. It was discovered in 2005 during the INT Photometric Hα Survey (IPHAS) and is classified as a relatively evolved object with low surface brightness, making it challenging to observe without specialized equipment.
Characteristics
It is surrounded by a faint, irregular shell, which may represent an asymptotic giant branch (AGB) remnant and the central star might be a white dwarf or an early multiple-shell structure. This shell suggests minimal distortion in the main nebula, classifying it as a WZO1-type planetary nebula-interstellar medium (PN-ISM) interaction candidate, where the central structure remains largely unaffected, possibly with a distant bow shock.
12Sabin, Laurence; Zijlstra, Albert A.; Wareing, Christopher; Corradi, Romano L. M.; Mampaso, Antonio; Viironen, Kerttu; Wright, Nicholas J.; Parker, Quentin A. (2009-12-30), "New Candidate Planetary Nebulae in the IPHAS Survey: The Case of Planetary Nebulae with ISM interaction", Publications of the Astronomical Society of Australia, 27 (2): 166–173, arXiv:1001.0027, doi:10.1071/AS09046