Nick Hewitt started a programme to observe Abell planetaries a few years ago and I would like to continue this, although so far there has been little response (with the exception of a couple of observers). These planetaries were discovered by George Abell in the 1950s examining the Palomar Observatory Sky Survey (POSS) plates. They are usually large and therefore very old (in planetary nebulae terms). None of the objects are easy, and visual observers in particular will generally need large telescopes, pristine skies and nebula filters.
Owen Brazell and Stewart Moore, observing at the Equinox star party in 2003, observed several through Owen’s 20-inch Obsession, but none jumped out of the eyepiece. Abell 21-the Medusa Nebula – was seen, from relatively poor skies (mag. 5.2) at Stewarts previous house in Hampshire in his 14-inch, but he had generally failed more often than succeeded on others. However they should make good targets for imagers looking for something different. If anyone wants the list of Abell planetaries please contact the Director. There were 86 planetaries in his original list, but some were misclassified. Owen has also recently informed us that Abell 17 has just been reclassified as a plate fault – so much for all those US observers who claim to have seen it!
For those with poorer skies or smaller telescopes there are still plenty of under observed planetaries in the NGC and IC. I can understand people wanting to image M27 and M97 as they are beautiful objects, but there are lots of others that show considerable detail and I would like to put together a collection of images and visual appearances for the Section records. There are 94 planetaries in the NGC with many suitable for northern observers and some suitable targets include the following:
|NGC No.||RA (2000.0)
|Const.||Mag (v)||Mag c.s.||Notes|
|1501||04 07.01||+60 55.0||Cam||11.5||14.5||A lovely object. Responds well to OIII filter|
|1514||04 09.25||+30 46.9||Tau||10.9||9.4||Bright c.s and lovely surrounding nebula. Good with averted vision|
|1535||04 14.24||-12 44.5||Eri||9.6(p)||11.6||A wonderful object but quite low. Good without filter but superb with|
|2022||05 42.14||+09 05.4||Ori||11.9||14.9||Bright object in a nice star field. OIII filter gives little improvement|
|2242||06 34.12||+44 46.0||Aur||15.0||15.2||A challenging object. OIII filter of little use. Needs transparent sky|
|2346||07 09.40||+00 38.6||Mon||11.8||11.2||The Butterfly Nebula. Dominated by central star. OIII filter of little use|
|2371/2||07 25.55||+29 29.0||Gem||11.3||14.8||A double planetary. Seen as two objects with averted vision|
|2392||07 29.16||+20 54.8||Gem||9.2||10.5||The Eskimo Nebula. Structure seen in large apertures. Brilliant central star|
|2438||07 41.84||-14 44.2||Pup||11.0||17.5||Appearing as a little smoke ring in the field of open cluster M46|