Planetary Nebula IC 5117

IC 5117
IC 5117: Planetary nebula in Cygnus; 500 mm Cassegrain f=5800 mm f/11.4; SBIG STL11K; 50+50+50+50 min LRGB; Bernese Highlands; © 2005 Radek Chromik


The planetary nebula IC 5117 was discovered in 1905 by the Scottish-American astronomer Williamina Fleming. Dreyer described the nebula in his 1910 second index catalog as «planetary, stellar». [196, 315]

Physical Properties

In fact, with an angular extent of only 1.2 arcseconds, the PN can hardly be distinguished from a star. The apparent brightness measured in different filters: V 16.7 mag, J 11.3 mag, H 10.7 mag, K 9.5 mag.

IC 5117 is a very young and compact planetary nebula. The gas surrounding the central star is still very dense with 90'000 molecules per cubic centimeter and very hot with a temperature of 12'000 Kelvin. The central star is estimated to have a temperature of 120'000 Kelvin. The distance is estimated to be 3 kpc (about 9700 light years). Exact measurements are not available. [337]

«Strasbourg-ESO Catalogue of Galactic Planetary Nebulae» Acker et al., 1992 [141]
DesignationsPN G089.8-05.1: IC 5117, PK 89-05.1, ARO 112, VV 266, VV' 552
Right Ascension (J2000.0)21h 32m 31s
Declination (J2000.0)44° 35' 48"
Dimensions 1.2" (optical), 1.5" (radio)
Distance 2.5 kpc
Radial Velocity-26.1 km/s ± 1.3 km/s
Expansion Velocity 16.5 km/s (O-III), 21.5 km/s (N-II)
C-Star DesignationsAG82 431, CSI +44-21305 0, EM* CDS 1256, HD 205211
C-Star Magnitude17.5 mag (B filter), 16.7 mag (V filter)
C-Star Spectral TypeWR
DiscovererFLEMING 1905

Finder Chart

The planetary nebula IC 5117 is located in the constellation Cygnus (Swan). The best observation time is September to February

Chart IC 5117
Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]


141Strasbourg-ESO Catalogue of Galactic Planetary Nebulae; A. Acker, F. Ochsenbein, B. Stenholm, R. Tylenda, J. Marcout, C. Schohn; European Southern Observatory; ISBN 3-923524-41-2 (1992); (2021-02-18)
149SkySafari 6 Pro, Simulation Curriculum;
160The STScI Digitized Sky Survey;
196Celestial Atlas by Curtney Seligman; (2020-12-28)
315«Second Index Catalogue of Nebulae and Clusters of Stars; containing objects found in the years 1895 to 1907, with Notes and Corrections to the New General Catalogue and to the Index Catalogue for 1888–94» Dreyer, J. L. E. (1910); Memoirs of the Royal Astronomical Society. 59: 105–198; Bibcode:1910MmRAS..59..105D
337«Optical Spectrum of the Compact Planetary Nebula IC 5117» Siek Hyung, Lawrence H. Aller, Walter A. Feibelman, and Seong-Jae Lee; The Astrophysical Journal, Volume 563, Number 2; DOI:10.1086/323962