Astronomy:Abell 7

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Short description: Planetary nebula in the constellation Lepus
Abell 7
Emission nebula
Planetary nebula
Observation data: J2000 epoch
Right ascension 05h 03m 07.53s[1][2]
Declination−15° 36′ 22.7″[1][2]
Distance1.8 kly (0.55 kpcly
Apparent magnitude (V)Integrated: 12.2–14.3;[3] Central star: 15.4[2]
Apparent dimensions (V)12.733 × 12.733[1][2]
ConstellationLepus (constellation)
Physical characteristics
Radius8 ly (2.5 pc) ly
Notable featuresSimple spherical shape
DesignationsPK 215-30.1, PN G 215.5-30.8
See also: Lists of nebulae

Abell 7 is a faint planetary nebula located 1800 light-years away in the constellation of Lepus. It has a generally spherical shape about 8 light-years in diameter. Within the sphere are complex details that are brought out by narrowband filters. Abell 7 is estimated to be only 20,000 years old, but the central star, a fading white dwarf, is estimated to be some 10 billion years old.[3][4][5]


  1. 1.0 1.1 1.2 SIMBAD (4 August 2014), Results for PN A66 07, SIMBAD, Centre de Données Astronomiques de Strasbourg, 
  2. 2.0 2.1 2.2 2.3 "The Complete Abell Catalog of Planetary Nebulae". Astronomy Mall. Retrieved 2014-08-04. "MAG1 = Integrated VMag of PN / MAG2 = Mag of Central Star / SIZE = Diameter in arcminutes — ABELL:07 CON: LEP PNG# / OTHER: 215.5-30.8 MAG1: 13.2 MAG2: 15.4 SIZE: 12.7 RA: 05 03 07.5 DEC: -15 36 23 URA2: 137" 
  3. 3.0 3.1 Abell, George O. (April 1966), "Properties of Some Old Planetary Nebulae", Astrophysical Journal 144: 259, doi:10.1086/148602, Bibcode1966ApJ...144..259A 
  4. APOD (5 December 2013), Robert J. Nemiroff (MTU); Jerry Bonnell (USRA), eds., Abell 7, NASA,, "Very faint planetary nebula Abell 7 is some 1,800 light-years distant, just south of Orion in planet Earth's skies in the constellation Lepus, The Hare. Surrounded by Milky Way stars and near the line-of-sight to distant background galaxies, its generally simple spherical shape, about 8 light-years in diameter, is outlined in this deep telescopic image. ... Abell 7 itself is estimated to be 20,000 years old. Its central star is seen here as a fading white dwarf some 10 billion years old." 
  5. Abell, George O. (1955), "Globular Clusters and Planetary Nebulae Discovered on the National Geographic Society-Palomar Observatory Sky Survey", Publications of the Astronomical Society of the Pacific 67 (397): 258, doi:10.1086/126815, Bibcode1955PASP...67..258A 

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