Image Steve Gottlieb
The Abell Catalog of Planetary Nebulae was created in 1966 by UCLA astronomer George O. Abell (1927–1983) and was composed of 86 entries thought to be planetary nebulae that were collected from discoveries, about half by Albert George Wilson and the rest by Abell, Robert George Harrington, and Rudolph Minkowski.
|"P48 1994 Jean Large" by Picture scanned from the original by Michael Vergara|
Licensed under CC BY-SA 3.0 via Commons
Observing notes by Steve Gottlieb
Planetaries on the Abell list are best viewed with a large aperture telescope (e.g. 18-inch (0.46 m)) and an OIII filter.
Summer: 17.5: at 200x and 140x using an OIII filter appears faint, moderately large, ~50" diameter, round. Can hold continuously with averted vision and visible with direct vision. Did not look unfiltered for the mag 15 central star.
13: at 79x with OIII filter appears extremely faint, moderately large, 1.0' diameter, almost round, can barely hold steadily. Just visible using a UHC visible although appears near the visual threshold.