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LCROSS impact plumes contained moon water, NASA says

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Cabeus crater LCROSSA spacecraft that performed a choreographed, two-part dive into the lunar surface in October churned up detectable levels of water ice, NASA announced Friday.

The Lunar Crater Observation and Sensing Satellite, or LCROSS, chased a spent Centaur rocket stage toward the moon to observe the booster’s impact into a permanently shadowed crater known as Cabeus near the lunar south pole. The satellite then crashed into Cabeus itself.

Before its impact, the main craft’s spectrometers collected enough data from the Centaur plume to indicate the presence of liberated water. The spectra gathered by LCROSS, project scientist Anthony Colaprete said in a prepared statement, could only be reconstructed if water was assumed to be present in the plume. "No other reasonable combination of other compounds that we tried matched the observations," he said.

According to, Colaprete estimates that the spacecraft detected 100 kilograms—about 25 gallons—of water. Such stores could be invaluable for future lunar explorers, who could save vast amounts of launch weight by tapping into the moon’s own water resources rather than bringing their own.

The mission, which began with a June launch alongside NASA’s Lunar Reconnaissance Orbiter, sought to resolve long-detected hydrogen concentrations at the lunar poles, from which the presence of water had been inferred. But a similar impact by the Lunar Prospector spacecraft in 1999 failed to dig up sought-after water ice, which could remain trapped in significant amounts in the moon’s shadowy craters.

A team of researchers announced in September that they had uncovered evidence from other spacecraft for widespread water distribution across the lunar surface, but in much sparser concentrations than what LCROSS found in Cabeus.

Photo of Cabeus crater floor and the impact scar left by the Centaur rocket stage: NASA

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  1. 1. Quasimodo 7:20 pm 11/13/2009

    The little article is fine. It’s the way NASA is handling information that has me riled. I suspect NASA has sensor recordings of several kinds that recorded the LCROSS impact events. Why won’t NASA come down off its little hill and treat us tax payers the way it should? Phooey. NASA wants the dough but holds on to the good stuff. Are you telling me that the scientists’ proof is that blurry little photo? I don’t believe that. Why hasn’t NASA shown us the conclusive evidence?
    What the beep! I’m not into conspiracies, but the way NASA’s people are disclosing revelations is suspicious.

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  2. 2. hotelsierra51 6:31 am 11/14/2009

    Nasa’s showing indeed the IR- and UV-spectra on their site that show evidence of water vapor and hydroxyl, so I think that part of the story is correct. But they state that any contamination of the Centaur is ruled out. The Centaur upper-stage however is propelled by liquid hydrogen and oxygen, elements that combine to the detected water and hydroxyl.
    Now I wonder how Nasa can be so sure that what they detected is not residue of the propellant in the Centaur? After all this discovery comes on a time that may be very convenient to some moon-base addepts.

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  3. 3. Michael Hanlon 8:55 pm 11/14/2009

    First ground penetrating radar indicated it might be there. Follow-u[ fly-overs indicated a possible rhime/frost in the shadows. Now a centaur sends up a 25 gallon geyser (OK maybe one gallon was from the rocket fuel) Let’s call the site "New Faithful" and let the Homesteading begin!

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  4. 4. Michael Cook 11:49 am 11/15/2009

    The problem I have with NASA’s credibility is that in my opinion they have used every excuse to confuse and distort the fact picture regarding global warming, particular regarding the data produced by satellites and their interpretation.

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  5. 5. Largo 10:28 am 11/17/2009

    Let’s be clear as to the comments so far entered, we do not trust the NASA to be an honest broker of information.
    I believe that the agenda of that agency is not aligned with the populace but with other agencies that wish to control controversy, to veil the reality discovered.
    This would be paranoid delusion except every datum is filtered, altered and regenerated to fit a set of paradigms. Raw information is never released except by accident.
    They are untrustworthy and any ‘discovery’ should be examined carefully as to why it was allowed, not that it was just made. That never happens.
    Agenda driven science is the hallmark here.

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  6. 6. Torino10 12:40 pm 12/8/2009

    Water on the moon is promising, but I have to wonder why NASA has not sent up the centrifuge for the ISS? If the ultimate long term goal of manned space flight is to be self sustaining colonies off of the earth then shouldn’t we be doing the science required to determine how people may be able to have children off of Earth? All Experiments on small mammals regarding this question have shown that embryonic development is very gravity dependent.
    It is imperative that we know if centripetal acceleration can be used as a substitute for gravity, how much gravity is required, and how long of a radius is required to minimize Coriolis effects and maintain the health of the mother.
    Current experiments do not bode well for any homesteading colonies on Mars, It may be easier to colonize bodies with lower gravity and no atmosphere where long radius centrifuges may be set up (a very fast moving train inside the walls of a crater, or hollowed out asteroids turned into O’Niel type colonys.

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  7. 7. Michael Hanlon 1:13 am 10/23/2010

    Update of 10/22/2010:::
    Ames/NASA today announced an update to the estimate of what happened as a result of this incident. A crater 1/4 the size of a US football field was excavated. In the debris plume they found evidence for 41 gallons of water (up from 25). They now guesstimate the amount of H2O in the crater to be 16 BILLION! gallons. Wish I could have heard Carl Sagan do that announcement. "Billions upon billions of frozen gallons of water on the Moon!"

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  8. 8. Michael Hanlon 1:32 am 10/23/2010

    Sorry, that’s reported to be ONE BILLION gals in that crater. There are other craters too, and what lies at the Moon’s North Pole?

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