The first quarter moon was beautiful tonight, as I gazed upwards after leaving the college music room where I have my weekly piano lesson. My senses are always extra keen afterwards. I took my 6 inch reflector out on the back deck as soon as I got home. Plunked a 6mm eyepiece in for a 133x look at the terminator. Yin and yang, the moon was split between dark and bright tonight.

My eye was immediately drawn to another dark and bright spot, the crater Arzachel. The western rim was brilliant and bright. The eastern rim and the valley floor were cloaked in darkness. The contrast reminded me of the entire lunar canvas on which this shadow play was taking place. In the middle of the darkness a spot of light, sunlight reflected off the central peak. Yin and Yang. How different this crater looks tonight when compared to the last quarter moon - the last time I sketched this lunar feature. On that night the crater floor showed terraced terrain half in shadow. The shadows were reversed.

Moving along the terminator Alphonsis was rimmed on both walls by lightness, while the crater floor rilles were hidden in shadow. Ptolemaeus, on the other hand was rimmed in shadow. The center of the plain partially in shadow. A beautiful contrast of light and dark, day and night.

Another triplet of craters yielded yet another different view. South of Arzachel, the walled plain Purbach was rimmed in shadow, the higher rocky middle darkly surrounded by light. The irregularly shaped Regiomontanus looks like it has been stretched out of shape. The floor, lit by the sun showed rocky geologic features, and a long shadow cast away from the central peak. Walter's crater walls were in shadow, as were the small craterlets within. Shadows snagged on rocky outcrops. No wonder first quarter moon is a favorite time for us lunatics. There's so much to savor on this night! The fog obscured the lunar shadowdance after a few hours, but it was time to go in and translate the visual images to words and pencil sketches and then to graphite drawings.