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April 13th, 2012, 23:20 - 23:40 UT, seeing fair - poor, transparency 5.
TMB 175mm f/8 apo refractor on a homemade Dobsonian-style mount. Magnification 170x- 298x. Filters used: Baader deep blue (W38A) and yellow (W25). South is at the top of this sketch, following is on the right hand side, north is at the bottom of the sketch, and preceding is on the left hand side. I used a Baader deep blue (W38A) and yellow (W25) filter for Venus, which seemed to help enhance the dusky appearance in clouds. It was similar to the last time I observed it but there were darker areas within the shading (like mottling) as well as lighter areas. These were not easy to represent in the sketch. The next morning I got up early and observed the last quarter Moon with the unaided eye. It reminded me of the view of Venus I had through the telescope the night before in terms of its phase as well as the dark lunar mare similar to shading in the atmosphere of Venus. |