Had a session last night using the 12.5-inch, but was disappointed with the seeing. Very watery and difficult to hold detail. I think the upper atmosphere was fine, but near the ground there was a lot of turbulence due to the temperature swing from the 90s to the 60s after dark -- too much heat being released by houses, streets, and the ground. Tonight's forecast is much the same, with great transparency and good seeing -- it's not as hot today so perhaps it will be better.
I only made two observations, Jupiter and Mars. Io had just started a transit when I began a little after 9pm, but I could not see its disk despite being at 340x (and the planetary filter & apodising screen). Not like Fremont Peak last month with the 20-inch, where we tracked Io as long as we wanted. My sketch reveals some largish festoons in the central band, but nothing remarkable. I observed Mars for a while then turned back to Jupiter at around 10:15pm to see Io's shadow, a very small round black dot on the NEB. Always nice to see a shadow transit; Jupiter is getting pretty low so there won't be many chances.
Mars looked better, using the same set-up. Syrtis Major was a prominently dark triangle near the western limb. I also observed the lighter sweeps of Sinus Sabaeus, Sinus Meridiani, and the beginnings of Mare Acidalium. Arabia was a clean clear orange color, with Eden pointed directly at me from the center.
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