I reobserved the marble green square area on the moon again last night. At low power (71x) it was still distinct from the brighter area but not quite as dark as it was the night before, likely from a change in the light angle (93% illuminated). Seeing was very good, so I ramped up power to 277x then 553x. The color change making the square was still very apparent, but there was a lot more fine detail to observe too, and I could see the delineation between the color changes was not as sharp as at low power.
Starting from Aristarchus: This crater has a bright wedge shaped ejecta field streaming toward Herodotus; these two craters take a corner off of the square. The darker area continues to Schiaparelli then takes a nearly right angle turn following Dorsa Burnet to Humason. The next turn seems to be at Nielsen and then back up to Aristarchus, with Rupes Toscanelli as the divider.
What was very interesting was a ghost crater (or is it called shadow crater?) which was a very old formation filled in with lava which had subsequently been deformed by later, smaller crater impacts. I could trace the sunken, faint round outline from Schiaparelli to below Montes Agricola and into that field. I don't find this traced on Rukl. Careful attention rewards the time and effort spent observing.
After only 40 minutes observing the moon went behind the meridian tree. I used my 7x35 binoculars for a while and was able to pick out some Messier objects despite the light pollution and nearly full moon: M31, M11, M13. Also the Coathanger and the lovely star fields of Cassiopeia. The sky around Delphinus and Sagitta was grainy, faint Milky Way stars wishing to be seen. New moon is coming up, I will have my chance.
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