pgc hunter
22-06-2010, 02:22 PM
After a solid month of solid overcast, a rare not-so-clear night presented itself.
With the moon nice and high, I ended up observing it for perhaps the better part of 2 hours. Seeing was very inconsistant, a bit mushy but with instances of crisp viewing. Patience was the word of the night ;) INfact, it might have been somewhat worse than average, as stars didn't focus as tight as they normally do at high power. Plus, there was extensive high cloud aswell.
Ofcourse, a few days ago I took the secondary mirror out, but after I re-installed it I forgot to collimate it and when it hit me, it was way too dark. But it seemed to look alright under the dim illumination of the car jump-starter light. Could be better though.
Date: 21/6/2010
Scope: 12" F/4.4 truss dob
Time: 7:45pm-11:30pm
Seeing: 4/10
Transparency: 1/5
After spending some 2 hours on the moon, I have made the following observations.
The view at 381x was very crisp, bright and sharp, I was surprised. Last time I remember observing the moon at this power, all I got was a fuzzy ill-defined view. I increased power to 534x which I settled on, and while seeing was blurring every now and then, there were instances of remarkable detail.
For Plato observations, I am using David Knisley's excellent guide:
http://www.cloudynights.com/ubbarchive/showflat.php/Cat/0/Number/520616/page/0/view/collapsed/sb/5/o/all/fpart/1
Plato
The Big 4 craterlets A,B,C,D were amazing at 534x, nice big pits with the shadows of the rims across their floors. C and D were well resolved with a nice big wide gap between them. Craterlet G was resolved into a pit and H was seen aswell, but a double with two tiny pits, it was not resolved as such. Cratelet E was easy, also resolved into a pit.
Also spotted I, J, K, N, P. THese were much more difficult, but in moments of steady seeing, were obvious, particularly I and J. I could even resolve I and J into tiny pits at 534x momentarily in bouts of good seeing. The most difficult of this lot were K, N and P, all three only seen as tiny white spots intermittently. I may have suspected resolving the pit of K, but cannot confirm.
Other features seen on Plato inlcude a tiny area of brightness between craterlet E and P, and a "ribbon" of bright material across the northern side of the crater.
Rupes Recta (straight wall)
Fantastic at 534x, certainly didn't appear straight that's for sure! THe wall appeared very uneven, and some "peaks" or "benches" could be seen in the sunlight in the otherwise dark area from the shadow of the wall itself.
Alpine Valley
Nice wide cavern at 534x, could even see the Rille down in the valley floor.
--------------------------------------------------------
Spent some time cruising the lunar terminator, and was amazed at the detail, particularly Copernicus at 534x. Those terraced walls were killer, the intense detail in the crater floor, can't explain it, it's like severe granularity in a globular cluster or a mass of grapes or something.
With the moon nice and high, I ended up observing it for perhaps the better part of 2 hours. Seeing was very inconsistant, a bit mushy but with instances of crisp viewing. Patience was the word of the night ;) INfact, it might have been somewhat worse than average, as stars didn't focus as tight as they normally do at high power. Plus, there was extensive high cloud aswell.
Ofcourse, a few days ago I took the secondary mirror out, but after I re-installed it I forgot to collimate it and when it hit me, it was way too dark. But it seemed to look alright under the dim illumination of the car jump-starter light. Could be better though.
Date: 21/6/2010
Scope: 12" F/4.4 truss dob
Time: 7:45pm-11:30pm
Seeing: 4/10
Transparency: 1/5
After spending some 2 hours on the moon, I have made the following observations.
The view at 381x was very crisp, bright and sharp, I was surprised. Last time I remember observing the moon at this power, all I got was a fuzzy ill-defined view. I increased power to 534x which I settled on, and while seeing was blurring every now and then, there were instances of remarkable detail.
For Plato observations, I am using David Knisley's excellent guide:
http://www.cloudynights.com/ubbarchive/showflat.php/Cat/0/Number/520616/page/0/view/collapsed/sb/5/o/all/fpart/1
Plato
The Big 4 craterlets A,B,C,D were amazing at 534x, nice big pits with the shadows of the rims across their floors. C and D were well resolved with a nice big wide gap between them. Craterlet G was resolved into a pit and H was seen aswell, but a double with two tiny pits, it was not resolved as such. Cratelet E was easy, also resolved into a pit.
Also spotted I, J, K, N, P. THese were much more difficult, but in moments of steady seeing, were obvious, particularly I and J. I could even resolve I and J into tiny pits at 534x momentarily in bouts of good seeing. The most difficult of this lot were K, N and P, all three only seen as tiny white spots intermittently. I may have suspected resolving the pit of K, but cannot confirm.
Other features seen on Plato inlcude a tiny area of brightness between craterlet E and P, and a "ribbon" of bright material across the northern side of the crater.
Rupes Recta (straight wall)
Fantastic at 534x, certainly didn't appear straight that's for sure! THe wall appeared very uneven, and some "peaks" or "benches" could be seen in the sunlight in the otherwise dark area from the shadow of the wall itself.
Alpine Valley
Nice wide cavern at 534x, could even see the Rille down in the valley floor.
--------------------------------------------------------
Spent some time cruising the lunar terminator, and was amazed at the detail, particularly Copernicus at 534x. Those terraced walls were killer, the intense detail in the crater floor, can't explain it, it's like severe granularity in a globular cluster or a mass of grapes or something.