All weekend I've been telling people that the mainstream media (MSM) have been missing the best part of the LCROSS lunar impact story. The MSM have reported that it was a dud, a failure. They were SO disappointed that they didn't see any of the expected debris plume. There was a brief flash of sodium light on impact (seen in mid-IR wavelengths by the trailing spacecraft) but no ejecta.
But maybe this was not so much a mission failure as a reality check from the Moon itself. The NASA press office was simply following the lead of the scientists, who all expected a pretty ejecta plume that people with telescopes (or a TV set) could see & enjoy. They didn't really overhype the story in their press releases, they were all caught of guard by the unknown conditions on the crater floor. That there was no plume is a heck of a story in itself and the MSM just didn't get it.
Fly that Centaur upper stage into the Moon anywhere else and you will get a regolith explosion and a very pretty conical cloud. But whatever LCROSS hit didn't do that.
I've been telling anybody who'd listen that the booster must've hit ices that were internally shaped like a sponge. The energy of the impact was dissipated into the interstices of the ice, where there are gaps & voids left by sublimation. Rather like the aerogel that captured cometary dust particles a couple years ago. Take the green foam material that florists use (called Oasis) and jab a pencil into it and you get an idea of what happened.
However, Spaceweather on Sunday the 11th. got it right:
"The absence of debris plumes does not mean LCROSS was a failure. On the contrary, by offering up the unexpected, LCROSS is teaching us something new about the lunar surface and the products of lunar impacts. That makes it, by definition, a successful experiment. All that remains is to figure out what the new information is. Researchers will be announcing their findings in the days and weeks ahead. Stay tuned."
Now if only MSM paid attention to science bloggers they could've gotten it right too. They've fired all their science reporters and now the reporters they're left with haven't a clue what they're writing about. The NASA press office needs to get busy getting things straightened out and the real story out there.
It's probably a good thing long term that we didn't make a debris plume. The ices would've largely gotten sublimated to gas and blown away by the solar wind. What a waste. Now the ice is still there, but we have to send a rover down into the crater to discover it.