I would like an explanation please of the following. Saturday, May 2 at Kartchner Caverns State Park, was the middle of the four day Astrofest with speakers and nightly star parties. Towards sunset the sun was shining through high cirrus clouds. A large section of the clouds southeast of the sun became incredibly brilliant mother of pearl blue and rich aqua green. This area was NOT 22* south of the sun and absolutely NOT sundogs, nor were they in line to be sun pillars. In fact the phenomenon was not at all symmetrical. What is this? Bill Peters afls@xxxxxxx -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.