Davesellars Posted May 10, 2017 Share Posted May 10, 2017 Well it cleared over yesterday evening around 8pm. Once the kids were in bed I packed and lugged the 120ED to my site for observing Jupiter and a bit of lunar shenanigans. First thing.. once I was there. Man, our Moon was throwing out some severe LP! I could only make out 3 stars in Ursa Minor. Megrez, in UMaj was barely visible so I guess limiting magnitude was about mag 3.5... uurgh. I've never see so few visible stars at my site. Humidity was definitely already in the air and the temperature was dropping rapidly. While the refractor was cooling down I pointed it at the Moon at low power and nearly burnt my eye out so moved quickly to rather higher power with the 6.7mm giving 134x. Still rather wavy but I think the tube still has internal thermals. Also some false colour and glare I assumed to do with the scope cooling. over the next 20 mins or so the view improved considerably and was rather more stable. Still the seeing wasn't all that but the 10mm BCO really gave a nice view - natural and sharp. I studied the Grimaldi crater and Rimae Riccioli above which was a very pronounced crater on the edge which was catching perfectly the contrast of deep shade and highlight on the ridge. On the north rim Barrow and W. Bond showed a really great 3D like view of the craters edges. The south showing considerably more contrast and mountainous. Later I revisited at 191x with the 4.7mm eyepiece to extract more detail around these regions. The seeing would not have supported any more power it was slightly wavy as it was. Before hitting Jupiter I spotted the double star Gamma Virginis (Porrima) close by Jupiter's position. Gamma Virginis - with the 6.7mm (134x) this showed the slightest of separation with identical colour and brightness of the two stars. Going to 191x was ideal and the separation was much clearer. Looking at the info on SkySafari suggests this has 2.6" of separation. I think quite a good subject to test optical quality with the brightness of the two stars? Both stars showed equally a nice golden yellow colour. Jupiter - the GRS was in transit and in a great position be seen. My 3rd time this year to see it! At 134x the colour is really prominent terracota orange and oval. It looks quite seperated from the South belt with a large cream band between it and the belt hooking round indenting into the band. At 191x I had to really concentrate to catch the very slight patches of good seeing but the GRS showed really nicely and defined at this power. Fine cloud bands both north and south apart from the main belts were easily seen and slight difference in colour and detail in the main belts. 3 moons visible all quite close to the planet framed it nicely. It was getting definitely soupier quite quickly and cold to boot... I carried on. I spent about an hour with Jupiter and switching back to view the Moon. I popped in the 32mm Baader Plossl which provided a really nicely contrasted view but also a bright line of CA on the edge. After blinding myself again with the Moon I packed up. Everything was pretty much frozen and extremely damp and I could see a bank of freezing fog coming in. Indeed when I looked back at my site I was indeed sitting in quite a bank of freezing fog myself. Glad I took my winter gear with me!p but I was still pretty cold by the end of it and glad to get back to warm up... apparently the temperature dropped to -2C. :p. 7 Link to comment Share on other sites More sharing options...
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