Jupiter with 12" dob - Observation Report

[SAB]

I was outside on the morning of May 24, 2008 with the 12" truss dob doing a spot of open cluster hunting while waiting for jupiter to rise.

It was a very cold morning, about 2ºC. The coldest May morning since 1981. Seeing wasn't that good, but was reasonable, I'd rate it perhaps 5-6/10. My observation of jupiter was at about 1am, with the planet well positioned high above the horizon.

Anyway, my first look of Jupiter using the 12" dob was one of the most memorable! I was astounded at all the detail I could see. The moon was nearby and was shining into the scope so stray light was an issue. I tried the 8mm Vixen LVW first for 172x and the disk was pretty sharp, but you could see the seeing was blurring it a bit. However, the detail was amazing! I thought it could use a bit more mag so I barlowed the 13mm LVW for 217x and yes it was remarkable. During good moments, Jupiter looked almost like a friggin' photo!!! What struck me was how incredibly detailed and complex the SEB was. You could see all those swirls, rifts, ovals and whatnot that are so characteristic of the amateur photos you see. The NEB was showing a clearly irregular outline, with 2 distinct lowerings. The EQ zone was loaded with festoons, which were low contrast and susceptable to the seeing but were clearly bluish compared to the brown NEB and the greyish/salmon pink SEB. I could spot 4 other razor thin belts in the North temperate area plus another two in the Sth temperate area. Just below the SEB were what appeared to be a series of brown "blobs" - perhaps storms.

I spent perhaps an hour in the freezing cold, in the heavy dew just sitting at the eyepiece. I shudder to think what I'd see in very good seeing!