Just back from a great holiday that started with a 7 night cruse from Luxor to Aswan with Abercrombie & Kent. Absolutely excellent, would recommend them to anyone. Then we to Mt Siani with some good friends of ours for new year. It was there that we saw this Halo above St Catherine's monastery. Makes a rather pleasing photo, feel free to use this image to support your physics teaching if you want to (please remember to cite this blog).