NASA’s LCROSS team — which sent an empty rocket stage smashing into a lunar crater on 9 October — says it caught a debris plume on camera. They probably felt the need to cough up some sort of plume — circled here in red — after some muttering that the event had been over-hyped. Dozens of professional telescopes — along with hundreds of amateurs — had observed the impact to no apparent avail.

But in an accompanying press release, NASA says that the plume rose between 6 and 8 kilometres in the air, after an impact scoured out a crater 28 metres wide. If the plume rose so high, then why have so few spotted it? In its guide to amateurs, NASA said anything above three kilometres would have risen above crater walls and been illuminated by the Sun.

New Scientist has a story that quotes lunar scientist Paul Spudis, who says that even if LCROSS did find water, it was more of a “PR stunt” than anything else. Even if LCROSS finds water in its spectral analysis of the plume, he says, it will only be from one spot, even though it now appears that there is evidence for water distributed all around the Moon’s poles, albeit in a spotty way.

Image: NASA