itwbennett writes "Tomorrow morning at 7:30 EDT, NASA is going to crash a probe into the moon as part of its LCROSS (Lunar CRater Observing and Sensing Satellite) mission, the main purpose of which is to discover if there's any water on the moon. 'If you happen to have a 10-12" telescope (or larger) then you might be able to see the plume from your backyard,' says blogger Peter Smith. 'For the rest of us, the impact will be streamed live over the web in a few places. NASA will have a feed, beginning at 6:15 EDT. The NASA feed includes live footage from the spacecraft itself as well as expert commentary and other goodies. Astronomy service SLOOH is offering a double-shot of earth-bound feeds, with one feed from New Hampshire and the other from Arizona. The SLOOH feeds start at 6:30 am EDT.'" Update:
Matt_dk adds a link to a viewing guide to the impact
, writing that "Amateur astronomers need a 10-inch or bigger telescope to make observations."