G'Day wonderful imagers…
I am presently writing an article on the only planetary nebulae in Mensa on K1-27.
Question please. Has any amateur actually imaged this Mensa object?
K1-27 / ESO 33-33 / PK 286-29.5 / P NG 286.8-29.5 (05570-7540) is a faint but (the only) sizeable PNe in Mensa, which was found by Kohoutek in 1977. Now listed as K1-27, this is a confirmed high excitation PNe of significant age. In size, K1-27 covers some 46 arcsec across
The specific area where this faint nebulous object lives is easily found, but revealing the little beastie in not for the faint of heart or those with poor observing city sites or in having mediocre vision - except of course for imagers. Its elusive nebulosity was earlier missed by many observers, and was not even found by Karl Heinze, because it lay well outside the the range of his “He2-” catalogue of Milky Way the haven for most known PNe along the galactic plane.
The white dwarf central star has been identified as 16.7 magnitude, being a probable physical pair whose component is 0.56 arcsec in PA 315 degrees according to Ciardullo et al. (1999). This is the white-dwarf WD 0558-756, being a rich DO-type planetary nebula nucleus. An exact position for the planetary is 05h 57m 02.10s -75° 40' 21.0". Distance is about 1.2 kiloparsecs.
Cheers.