[sculptor]

Anyone got some recent data on Porrima (gamma virginis)? According to Hartung it is supposed to be a Romp-It-In 3" arc. Last night I had a go at resolving it with a York Optical 6" refractor (focal length 900 mm). Nothing like 3". I added a Tele Vue x4 and a 13 mm eyepiece, which effortlessly resolves eta orionis at 1.4" arc with room to park a bar-fridge in between the stars. Nothing. Switched to an 8mm eyepiece (450x), which is theoretically beyond the ability of the instrument. Now Porrima was clearly resolved (ie not just elongated), with a position angle of around 45 or 235 deg (the two stars are equally bright). I am guessing the separation is around 0.6" arc.

A look round the web shows Porrima was closest round 2005 at 0.3" arc.

Interestingly, the 11" Celestron SCT had no hope of resolving it. "Economical" light buckets seem good at photographing faint galaxies (see NGC 2997 attached: Mag 9.7, size 10' x 7' arc, SB 13.5 or so) not resolving doubles.