Object: Constellation: Coordinates: Size: Brightness:
Abell 72
(= PK 059+18.1)
Del 20h50m / +1333' 2.2' x 2.0' 13.8mag

The faint planetary nebula Abell 72 (PK 059+18.1) in the constellation Delphinus on July 24 / 25, 2014 and on July 29 / 30, 2016. Abell 72 is an expanding glowing shell of ionized gas ejected from an old red giant star. The beautiful object of George O. Abell's Catalog of Planetary Nebula is 5'700 ± 1150 light years from earth and about 2 light years across. (Sources: The binary fraction of planetary nebula stars, Mon. Not. R. Astron.Soc. 000,000-000 (0000), Oct. 2012; Wikipedia).

Forty-four 3 minute exposures at ISO 800 with no dark frame subtraction were stacked with Deep Sky Stacker (resulting in a 2 h 20 min exposure) and further processed in Adobe Photoshop.
Equipment: Canon EOS 450D Baader modified camera, TeleVue Paracorr Type II coma corrector, 16" f/4.5 "Ninja" dobsonian telescope riding on a dual-axis Tom Osypowski equatorial platform, Lacerta MGEN autoguider, Lacerta off axis system (field of view comparison: image of the moon with the same equipment).

Star hopping to Abell 72: A nice starting point are either the stars β and η delphini or the fainter stars 15, 16 & 17 delphini. Map © 2015 "The Mag-7 Star Atlas Project", www.siaris.net. Map is modified. The map can be downloaded here .

Search chart for Abell 72. Star hopping from an area close to β and η delphini. The circles correspond to a 1.5 field of view (e. g. a 40 mm 65 eyepiece on a 16" f/4.5 telescope). 15, 16 & 17 delphini make another good starting point for Abell 72 (especially if visible by the naked eye). Map © 2015 "The Triatlas Project", www.uv.es/jrtorres/triatlas.html. Map is modified.