Now basically it was clear, right, So I figured I'll do some deepsky before the moon comes back. My customary check of Sirius and its amount of twinkling suggested seeing might be alright. The latest jetstream maps didn't look spectacular, but in reality, seeing was actually quite good. The transparency on the other hand wasn't much good at all.
Once again, I found a strand of spider web in the dob, so using my noggin I discovered a new way to cool the scope down. I covered the front with a plastic shower cap so no crap can get in and inserted the cheshire into the focuser with the side hole sticking out to allow the fan to blow the air out the cheshire, just like a chimney. This way, the warm boundary layer air can break up and be expelled while the scope is protected from crappy little bugs.
Scope: 10" GSO Dob
Seeing: 7/10 (NO WAY!)
Transparency: 3/5
Times: 11:30pm-2:30am
NGC 1535
This is a bright and greenish planetary in Eridanus. At low power my 10" shows a non-stellar fuzz. Higher powers bring out a greenish ring with a bright central star, surrounded by a larger, circular haze. Dropped in the 5mm LVW and 2.5x Powermate for 625x, my 10" dob showed an obvious ring, surrounded by a large haze which was best seen with averted vision. At this magnification, I could resolve some detail in the centre, with the central region noticably uneven in brightness. My sketch bears surprising resemblance to one amateur photo of this planetary.
B706
Double star in Canis Major. Decided to revisit this as the seeing was good. Very tight 0.6" seperation, with both components approximately equal magnitude and sporting an orange colour. Like everything else awesome in the southern hemisphere, it was well inside Dobson's Hole. So I to jerk and yank the scope because frankly, dobs don't like moving when aimed 85º up! At 357x, the split was almost easy! Yes, there was an obvious hairline gap. I tried 500x, and while seeing was periodically smudging the pair, the split was clear.
HU 1443
Another tight double, this one in Carina. A difficult 0.8" split, with the pair being uneven in magnitude - 7.9 and 8.6. At 357x, I couldn't split it. Using 500x gave a better view, with the split just evident during spit second moments of good seeing. In my opinion, this pair is much tougher than the 0.6" BU706.
M42
The trapezium stars appeared as clean as I've ever seen them at 625x, focusing down to tight airy disks, however a combination of tube currents and seeing still distorted the diffraction pattern. At this magnification, the nebula is superbly detailed with texture and mottling galore.
NGC 3211
A small planetary in Carina, due west of the "southern Pleiades". Barely non-stellar at 56x. The 10" at 357x without the narrowband filter showed a small, slightly oval disk. Listed as being magnitude 12.6, with a diameter of 16". At 357x and 500x with and without the filter, annularity could be detected, however the central region was only barely dimmer than the outer ring. The filter at 500x provided the best view.
IC 2553
A small, 9" planetary just over a degree WNW of NGC 3211. Distinctly elongated at 500x. Didn't get a good view as I lost it and couldn't be bothered juggling eyepieces to re-aquire it!
Eight Burst Planetary
My 10" showed a distinct 'C' shape ring at high powers, noticably uneven in brightness. The ring appeared brighter along the longer axis. The central portion within the ring is uneven in brightness. Using the narrowband at 357x provided the best view. I didn't try higher mags as I deemed it unnecessary.
Ghost of Jupiter
Features a strong bluish colour. The CBS eye shape and central star was clear and crisply defined at 250x without the filter. Increased magnification to 500x and it is now that I discover how large this planetary really is. The eye shape was still crisp and contrasted well with the faint outr halo.
Saturn
Moments of good seeing provided exceptionally crisp views at 156x. The 10" made easy work of the cloud belts and Cassini division. Dropped in the 5mm LVW for 250x and during a single moment of good seeing lasting a few seconds, I got a view that far exceeds anything I've seen before in any telescope. The Cassini Division at the ring tips was a gap with thickness rather than a thin line, the shadow of the rings on the globe was jet black and etched with knife-edge contrast and the cloud belts were crisply defined. The crepe ring also presented itself. Now that was 10 seconds of premium viewing that will be hard to surpass given Saturn's poor position.
At this point it was 2.30am and ofcouse the usual Melbourne clouds moved in to spoil the party...as per ****** usual. However, Melbourne's **** climate was not enough to sour this excellent night!
Did some sketches which I'll post later.
