LCROSS, the Lunar Crater Observation and Sensing Satellite launched in June, will be crashing into the Moon next month. And now we know exactly where it will crash into the Moon. The upper rocket stage that launched LCROSS will be crashing into the permanently shadowed parts of the crater Cabeus A near the Moon's south pole, which will kick up a huge plume that LCROSS will observe. And it will be soon followed by the crash of LCROSS itself, which will kick up a smaller plume that telescopes on Earth could observe.
With any luck, there will be water in the permanent shadows around the Moon's south pole, and LCROSS will be able to definitely confirm its presence.