While not an atmospheric phenomena, still interesting, how about a Lunar Transit of the Sun Check http://science.nasa.gov/headlines/y2007/12mar_stereoeclipse.htm?list195632 Jeff At 14:36 -0700 03/12/2007, ketelsen@xxxxxxxxxxxxxx wrote: >So is there any agreement on what would be "the rarest of all naturally >occuring atmospheric phenomena" (notice - no shouting)? I suspect we >would have to get specific on location - aurora are rare at the equator, >but not so much in Alaska... > >-Dean -- Jeff Hopkins HPO SOFT Counting Photons http://www.hposoft.com/Astro/astro.html Hopkins Phoenix Observatory 7812 West Clayton Drive Phoenix, Arizona 85033-2439 U.S.A. (623)849-5889 (623) 247-1190 (Fax) www.hposoft.com -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.