Planetary Nebula Abell 39

Abell 39
Abell 39: Planetary nebula in Hercules; 500 mm Cassegrain f=3625 mm f/7.2; SBIG STL11K; 440+3*70 min LRGB; Bernese Highlands; © 2015 Radek Chromik

History

The planetary nebula Abell 39 (PN A55 27, PN A66 39, PK 47+42.1) was discovered in 1955 by the American astronomer George Ogden Abell on the photo plates of the «Palomar Observatory Sky Survey» (POSS). In 1966 he published a list of a total of 86 planetary nebulae discovered on the POSS photo plates. [331, 332]

Physical Properties

Abell 39 shows an almost perfect spherical bubble like a picture book for a planetary nebula. The western edge is about 50% brighter than the eastern. The central star is also not exactly in the center, but offset by about 2". It seems that this is due to a slightly asymmetrical ejection of matter and not an interaction with interstellar matter. It is estimated that the central star and the ejected material each have 0.6 solar masses. [333]

Distances from planetary nebulae are naturally quite imprecise. Those of Abbel 39 range from 1011 parsecs (2018) to 1175 parsecs (2008), which corresponds to 3300 to 3800 light years. Older estimates are at 2100 parsecs, about 6800 light years. The apparent brightness is measured by different filters: B 15.27 mag, V 15.6 mag, J 16.1 mag. [145]

«Strasbourg-ESO Catalogue of Galactic Planetary Nebulae» Acker et al., 1992 [141]
DesignationsPN G047.0+42.4: A 39, PK 47+42.1, A55 27, ARO 180, VV' 140
Right Ascension (J2000.0)16h 27m 34s
Declination (J2000.0)27° 54' 35"
Dimensions 174." (optical)
Expansion Velocity 32. km/s (O-III), 37. km/s (N-II)
C-Star DesignationsAG82 209, CSI +28 -16255, UBV 13929
C-Star Magnitude14.10 mag (U filter), 15.34 mag (B filter), 15.69 mag (V filter)
C-Star Spectral Typesd O, Hg O(H)
DiscovererABELL 1955

Finder Chart

The planetary nebula Abell 39 is located in the constellation Hercules. The best observation time is April to August.

Chart Abell 39
Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

References

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); cdsarc.unistra.fr/viz-bin/cat/V/84 (2021-02-18)
145SIMBAD astronomical database; simbad.u-strasbg.fr/simbad
149SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
160The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
331«Globular Clusters and Planetary Nebulae Discovered on the National Geographic Society-Palomar Observatory Sky Survey» Abell, G. O.; Publications of the Astronomical Society of the Pacific, Vol. 67, No. 397, p.258-261, August 1955; DOI:10.1086/126815; Bibcode:1955PASP...67..258A
332«Properties of Some Old Planetary Nebulae» Abell, G. O.; Astrophysical Journal, vol. 144, p.259, April 1966; DOI:10.1086/148602; Bibcode:1966ApJ...144..259A
333«The Planetary Nebula A39: An Observational Benchmark for Numerical Modeling of Photoionized Plasmas» George. H. Jacoby, Gary. J. Ferland, and Kirk T. Korista; The Astrophysical Journal, Volume 560, Number 1; DOI:10.1086/322489