The moon for CERTAIN has no water?

More water on the moon September, 1998

There is more water on the moon than scientists had thought. Our science editor Dr David Whitehouse reports. Earlier this year scientists made the historic announcement that they had found ice on the moon buried at the lunar poles.

The discovery was made just weeks after the Lunar Prospector spacecraft entered the moon's orbit on the 16 January.

Water just below the surface

Refined calculations of the amount of lunar water are 10-times higher than the lower limit estimated earlier this year. The new research is published in Science magazine.

The new analysis also shows that the water is confined to localised areas near the poles, rather than spread out evenly across the polar regions, as was assumed.

The ice appears to be buried about half a meter beneath the lunar surface. There may be as much as three billion tonnes of water at each of the lunar poles. There may be slightly more at the north than the south pole.

When they presented their initial results in March, the scientists said that the water was likely in the form of a fine frost spread through the lunar soil. Further data analysis suggests the exciting possibility that their may be shallow deposits of ice.

The south polar region

Scientists assume that comets carried the water ice to the moon.

Lunar Prospector's instruments have also been surveying the moon's surface composition and have discovered that one well-known lunar feature - the huge Mare Imbrium basin - is unlike anything else of the moon.

"The mission has been an overwhelming success," said scientist Bill Feldman. "We have got beautiful science from two or three of our instruments. The third, we just have not had time to analyse the data yet."

According to another scientist working on the project, Rick Elphic: "We have barely begun scratching the surface of the analysis. We have not begun to touch on the many ramifications for the origin and evolution of the moon.

"Something special happened around Mare Imbrium - you do not see this sort of chemistry anywhere else on the moon."

Battling articles:

note the date

http://www.smh.com.au/articles/2003/11/13/1068674312947.html

Scientists await answer on water on moon

November 14, 2003

Looking for the lunar skating rink.

The latest effort by science to answer whether there's ice on the moon has come up empty.

There is no sign of a lunar skating rink in the mysterious polar craters - nor even a big slab of ice.

The results of the most detailed radar study of the moon's shadowy poles to date do not mean the moon is bone-dry. But the apparent lack of large ice tracts suggests there isn't a big supply of life-sustaining water nearby if people ever wanted to colonise the moon.

"It certainly would have been nice to find some sort of lunar skating rink, or thick layers of ice, but it looks like it's just not there," said Bruce Campbell of the Smithsonian Institution's Centre for Earth and Planetary Studies.

Five years ago, NASA's Lunar Prospector orbiter found tantalising evidence that deep, permanently shadowed craters at the moon's poles could harbor ice in their sunless depths.

Prospector found elevated levels of hydrogen - a component of water - around the moon's poles, with the highest readings in the perpetually shaded craters. But the evidence for ice was indirect.

Subsequent experiments that bounced radio waves off these craters revealed no sign of thick ice layers, although those tests penetrated only a few feet below the surface.

Now, Campbell and colleagues at Cornell University have used the mammoth radar dish at Puerto Rico's Arecibo Observatory to probe craters more deeply than ever before - as far as six metres down.

And still there's no sign of thick layers of ice.

Campbell and colleagues say their findings support the idea that any ice in the moon's polar regions is in thin layers or widely scattered crystals mixed in with lunar soil.

The findings appear in the journal Nature.

If the moon's poles do have widely dispersed ice, Campbell said that means moon colonists would need equipment either to sort ice particles from the soil or to heat up the crater floors and collect the water vapour.

Astronomers have suspected since at least the early 1960s that the moon's polar craters, kilometres-deep and surrounded by raised rims, could have trapped ice from comet impacts over billions of years.

Temperatures in some craters hover at about minus 173 degrees, forming "cold traps" where water could collect even as it escaped into space over the rest of the moon.

Alan Binder, the director of the Lunar Research Institute in Tucson, Arizona, said the new results are consistent with the Lunar Prospector's findings suggesting widely scattered ice, perhaps a few hundred million metric tonnes of it.

But the only way to know for sure is to send a human or robot.

"You've got to go down and stick your finger in it, so to speak," he said.

NASA has no lunar missions planned to address that question, but it is soliciting ideas for lunar spacecraft.