While surfing through Guy Ottwell's excellent "Astronomical Calendar" for 2007, I noticed that the maximum lunar libration for the year occurs on March 12. This means that features such as Mare Crisium will be shifted to nearly the limb while the crater Grimaldi will appear far less foreshortened. It also means that we can glimpse the great Orientale Basin for the next five nights or so. A search through the Cloudynights Lunar Observing archives turned up some good discussions about extreme librations. Mare Orientale isn't much to look at. Here are views compared for librations in longitude of roughly -4 and -7 degrees. http://tinyurl.com/4zy9n According to this libration calculator applet (http://www.jgiesen.de/moonlibration/index.htm), the libration on Saturday morning is -5.6d. By early next week, it will increase to -7.5d. It looks like the show is over by the 15th. Tom -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.