…dredging up approximately 385 tons of lunar dust and soil — enough to fill nearly 18 school buses. In addition to recording the collision, the shepherding spacecraft will fly through the regolith plume thrown up by the collision, just before it too slams into the lunar surface some four minutes later, kicking up its own smaller plume of debris.

In the minutes leading up to its sacrifice to the cause of science, the 1,500-pound (700-kilogram) shepherding spacecraft will use its specialized sensors to look for water’s telltale chemical signature within the larger debris plume created by the Centaur, possibly in the form of ice, hydrocarbons or hydrated materials.

[…]

Those who live to the west of Mississippi River will have the best opportunity, because the sky will still be dark. Those living east of the Mississippi will still be able to see the moon, but they’ll also have to contend with morning twilight or, in the case of those living along the Atlantic Seaboard, daylight after sunrise. That makes for a much brighter sky background.