Hi all! I said that posts would be sparse for a couple of weeks, but I didn’t realize quite how sparse! But I’m gradually getting back on-line here.
Right now, what’s occupying my attention for the next 48 hours is all in the sky: three crescents, and a ring. I’ll be brief, but if you want more explanation about the geometry involved, you might want to read my very relevant article about geometry and the beauty of the heavens.