Splash! NASA moon crash struck lots of water
LOS ANGELES — The lunar dud for space enthusiasts has become a watershed event for NASA.
Spacecraft that crashed into the moon last month kicked up a relatively small plume. But scientists have confirmed the debris contained water — 25 gallons of it — making lunar exploration exciting again.
Experts have long suspected there was water on the moon. So the thrilling discovery announced Friday sent a ripple of hope for a future astronaut outpost in a place that has always seemed barren and inhospitable.
"We found water. And we didn't find just a little bit. We found a significant amount," Anthony Colaprete, lead scientist for the mission, told reporters as he held up a white water bucket for emphasis.
He said the 25 gallons of water the lunar crash kicked up was only what scientists could see from the plumes of the impact.
Some space policy experts say that makes the moon attractive for exploration again. Having an abundance of water would make it easier to set up a base camp for astronauts, supplying drinking water and a key ingredient for rocket fuel.
"Having definitive evidence that there is substantial water is a significant step forward in making the moon an interesting place to go," said George Washington University space policy scholar John Logsdon.
The October mission involved two strikes into a permanently shadowed crater near the south pole. First, an empty rocket hull slammed into the Cabeus crater. Then, a trailing spacecraft recorded the drama live before it also crashed into the same spot four minutes later.
Though scientists were overjoyed with the plethora of data beamed back to Earth, the mission was a public relations dud. Space enthusiasts who stayed up all night to watch the spectacle did not see the promised giant plume of debris.
NASA scientists had predicted the twin impacts would spew six miles of dust into the sunlight. Instead, images revealed only a mile-high plume, and it was not visible to many amateur astronomers peering through telescopes.
Members of the blue-ribbon panel reviewing NASA's future plans said the discovery doesn't change their conclusion that the program needs more money to get beyond near-Earth orbit. The panel wants NASA to look at other potential destinations like asteroids and Mars.
"This new and terrific result reassures us about lunar resources, but ... the challenges currently facing the human spaceflight program remain," Chris Chyba, a Princeton astrophysicist who is on the panel, said in an e-mail.
President George W. Bush had proposed a more than $100 billion plan to return astronauts to the moon, then go on to Mars; a test flight of an early version of a new rocket was a success last month. President Barack Obama appointed the special panel to look at the entire moon exploration program. The decision is now up to the White House, and NASA's lunar plans are somewhat on hold until then.
As for unmanned exploration, previous missions had detected the presence of hydrogen in lunar craters near the moon's poles, possible evidence of ice. In September, scientists reported finding tiny amounts of water in the lunar soil all over the moon's surface.
But it was NASA's Oct. 9 mission involving the Lunar Crater Observation and Sensing Satellite, LCROSS, that provided the stunning confirmation announced Friday — water, in the forms of ice and vapor.
"Rather than a dead and unchanging world, it could in fact be a very dynamic and interesting one," said Greg Delory of the University of California, Berkeley, who was not involved in the mission, led by NASA's Ames Research Center in Mountain View, Calif.
The LCROSS spacecraft only hit one spot on the moon and it's unclear how much water there is across the entire moon.
Scientists spent a month analyzing data from the spacecraft's spectrometers, instruments that can detect strong signals of water molecules in the plume.
"We've had hints that there is water. This was almost like tasting it," said Peter Schultz, professor of geological sciences at Brown University and a co-investigator on the LCROSS mission.
Astronaut Buzz Aldrin, who in 1969 made his historic Apollo 11 moonwalk with Neil Armstrong, was pleased to hear the latest discovery, but still believes the U.S. should focus on colonizing Mars.
"People will overreact to this news and say, `Let's have a water rush to the moon,'" Aldrin said. "It doesn't justify that."
Mission scientists said it would take more time to tease out what else was kicked up in the moon dust.
AP Science Writer Seth Borenstein contributed to this report.
Copyright © 2009 The Associated Press. All rights reserved.
An artist's rendering of the probe approaching the Moon
"The argument that the moon is a dry, desolate place no longer holds water," says a press release from NASA. A Moon mission launched by the agency has confirmed the presence of water on the moon. The discovery comes a year after a NASA instrument on an Indian lander indicated there were water molecules on the surface of our satellite.

On September 24, 2008 the Indian Space Research Organisation had stated Chandrayaan-1 had discovered water based on readings from NASA's Moon Mineralogy Mapper, one of eleven instruments carried by the probe. Those results indicated water was widespread in low quantities. That probe, launched in October 2008, had to be abandoned on August 30 when contact was lost with it on the Moon's surface.

The new mission, called LCROSS, consisted of two separate spacecraft which travelled the 250,000 miles together in June before separating. An empty rocket slammed into the Cabeus crater, near the southern pole, while a small spacecraft stayed behind to take measurements from the plume of debris thrown up, although it too ultimately crashed into Cabeus. Across the United States people spent the night on lawns and in parks hoping to see the impact, on the 40th anniversary of the first Apollo Moon landing, but it was invisible to the naked eye. NASA had predicted a visible six-mile plume; the reality was only a mile high.

The twin impacts on October 9 are now known to have sent 25 gallons of water ice and vapour into the air amongst the debris kicked up from the 60 to 100 foot wide hole produced by the rocket. This amount only accounts for the debris scientists could actually see over the rim, and the remaining debris could contain more water. It is unclear how much water may be distributed accross the Moon, although hydrogen at the poles suggests water ice there. 

LCROSS stands for lunar crater observation and sensing satellite, which was the satellite's name, while its rocket companion was called Centaur. It took a month to analyse the spectrometer data from the mission, and efforts are ongoing to determine the composition of the remaining material kicked up out the crater. The whole project cost $75 million.

"We got more than just whiff. We practically tasted it with the impact," said project co-investigator Peter H Schultz. The material thrown up split into a curtain travelling sideways and a plume that passed the crater's rim, bringing it into the sunlight for the first time in billions of years. Both contained water. "We are ecstatic," said project leader Anthony Colaprete.
"We didn't find just a little bit, we found a significant amount."

Michael Wargo, who heads up lunar research for NASA, said "We're unlocking the mysteries of our nearest neighbour and by extension the solar system. It turns out the moon harbours many secrets, and LCROSS has added a new layer to our understanding." It is thought that by analysing the water we can learn of the moon's history, in a fashion similar to investigating Earth history with ice cores.

University of Maryland physicist Robert Park cautioned that people should not assume that water on the lunar surface would support a colony. "They've haven't found a big reservoir of it," he said. "I suspect this is just water clinging to the soil particles."

Buzz Aldrin, one of the first to walk on the Moon when he followed pioneer Neil Armstrong out of Apollo 11, said he was pleased by the news but added that "People will overreact to this news and say, 'Let's have a water rush to the moon.' It doesn't justify that." Aldrin wants the US to aim to colonise Mars, but NASA is looking at more lunar trips. Last month a new rocket was tested, and Barack Obama has set up a panel to look at possible Moon missions. George W. Bush had previously proposed a $100 billion programme to put more astronauts onto the Moon. NASA wants to return by 2020 and build a lunar base, allowing astronauts to remain for months at a time.