Planetary Nebula Abell 74

Abell 74
Abell 74: Planetary nebula in Vulpecula; 500 mm Cassegrain 3625 mm f/7.2; SBIG STL11K; 550-120-120-120 min LRGB; Bernese Highlands; © 2015 Radek Chromik [32]


This planetary nebula was discovered in 1955 by the American astronomer George Ogden Abell on the photo plates of the «Palomar Observatory Sky Survey» (POSS). In 1955 he published a first list of 13 globular clusters and the positions of 73 planetary nebulae. The PN had the number 61 (A55 61). In 1966 Abell published a complete list including the size and description of the 86 planetary nebulae discovered on the POSS photo plates. This planetary nebula was then number 74 on his list. The designation PK 72-17.1 comes from the two Czechoslovak astronomers Luboš Perek and Luboš Kohoutek, who in 1967 compiled a catalog of all the planetary nebulae of the Milky Way known at that time. [331, 332]

Abell 74
Abell 74: Image taken with Mosaic camera on Mayall 4 meter telescope at Kitt Peak Observatory. © 2020 T.A. Rector (University of Alaska Anchorage) and H. Schweiker (WIYN and NOIRLab/NSF/AURA) [596]

Physical Properties

Abell 74 is a large and extremely faint old planetary nebula, barely detectable on the POSS red photo plates. On the image of the Mayall 4 meter telescope (Fig. 2) it looks like a twin of the Dumbbell Nebula Messier 27, but it is much much fainter. Simbad lists a B magnitude of 16.91 and a V magnitude of 17.11. The distance was determined to be 657 parsecs by Gaia Early Data Release 3 in 2020. The planetary nebula is superimposed to the faint galaxy MCG+04-50-004 which has a B magnitude of 15.0. [145]

«Strasbourg-ESO Catalogue of Galactic Planetary Nebulae» Acker et al., 1992 [141]
Designations PN G072.7-17.1: A 74, PK 72-17.1, A55 61, ARO 193, VV' 546
Right Ascension (J2000.0) 21h 16m 52s
Declination (J2000.0) +24° 08' 51"
Dimensions 830." (optical)
Radial Velocity +18.0 ± 4.0 km/s
Expansion Velocity 27. (O-III) 26. (N-II) km/s
C-Star Designations AG82 425, CSI +23 -21146, FB 176, UBV 18389
C-Star Magnitude U: 15.72, B: 16.91, V: 17.11
C-Star Spectral Type sd Op
Discoverer ABELL 1955

Finder Chart

The planetary nebula Abell 74 is located in the constellation Vulpecula between Cygnus and Pegasus. The star patterns in the 1° closeup help to identify the position. The nebula it self is not visible to the eye and appears only after longer integration time. The best time to observe is March to December, when it is highest at night.

Finder Chart Planetary Nebula Abell 74
Planetary Nebula Abell 74 in constellation Vulpecula. Charts created using SkySafari 6 Pro and STScI Digitized Sky Survey. Limiting magnitudes: Constellation chart ~6.5 mag, DSS2 close-ups ~20 mag. [149, 160]

Objects Within a Radius of 15°