LCROSS mission (2009)
NASA deliberately crashed a Centaur rocket stage into the Moon's south pole on October 9, 2009, to study the ejecta plume. The mission confirmed the presence of water ice in permanently shadowed craters.
The impact created a visible plume and confirmed water ice.
It showed how impact ejecta can reveal subsurface composition, informing future lunar exploration.
LCROSS demonstrated the value of studying impact ejecta, which is what the McGetchin crater discovery also does.
