ScienceDaily (Sep. 24, 2009) — In a discovery that promises to reinvigorate studies of the moon and potentially upend thinking of how it originated, scientists at several research institutions have found evidence of water molecules on the surface of the moon.

The molecules and hydroxyl — a molecule consisting of one oxygen atom and one hydrogen atom — were discovered across the entire surface of earth’s nearest celestial neighbor. While the abundances are not precisely known, as much as 1,000 water molecule parts-per-million could be in the lunar soil: harvesting one ton of the top layer of the moon’s surface would yield as much as 32 ounces of water, according to scientists involved in the discovery.

Carle Pieters, a planetary geologist at Brown University, is the lead author of one paper this week in Science that reports evidence of water in the moon’s high latitudes — greatly expanding current thinking about where water in any form was presumed to be located.

“We’ve made a very important step with this discovery, and now there are some very important steps to follow up on,” Pieters said.

Professor of Geological Sciences Pieters is the lead investigator on the Moon Mineralogy Mapper (M3), a NASA instrument that was carried into space on Oct. 22, 2008, aboard the Indian Space Research Organization’s Chandrayaan-1 spacecraft. She said the findings from M3 reveal interesting, new questions about where the water molecules come from and where they may be going. Scientists have speculated that water molecules may migrate from non-polar regions of the moon to the poles, where they are stored as ice in ultra-frigid pockets of craters that never receive sunlight.

“If the water molecules are as mobile as we think they are — even a fraction of them — they provide a mechanism for getting water to those permanently shadowed craters,” Pieters said.

She continued, “This opens a whole new avenue [of lunar research], but we have to understand the physics of it to ultilize it.”

The M3 team found water molecules and hydroxyl at diverse areas of the sunlit region of the moon’s surface, but the water signature appeared stronger at the moon’s higher latitudes. The M3 discovery was confirmed by data from two NASA spacecrafts — the Visual and Infrared Mapping Spectrometer (VIMS) on the Cassini spacecraft and the High-Resolution Infrared Imaging Spectrometer on the EPOXI spacecraft. Data from those missions also are being published in separate papers in Science.

Pieters credited the Indian space agency for its role in the findings. “If it weren’t for them, we wouldn't have been able to make this discovery,” she said.

Other Brown members listed as contributing authors to the M3 paper include Brown planetary geology faculty James Head III and John “Jack” Mustard; postdoctoral research associates Rachel Klima and Jeffrey Nettles; and graduate student Peter Isaacson.

Isaacson said the M3 results were a huge surprise. “There was no evidence that this was possible on such a broad scale,” he said. “This discovery turns a lot of the conventional thinking about the lunar surface on its head.”

Mustard, who has had major findings of water-bearing minerals on Mars, said the moon discovery is “intriguing, because it shows water on a planet that we weren’t anticipating, and it’s in a form that’s mysterious. The finding may have implications for other planets, such as Mars, but it is different.”

From its perch in lunar orbit, M3’s state-of-the-art spectrometer measured light reflecting off the moon’s surface at infrared wavelengths, splitting the spectral colors of the lunar surface into small enough bits to reveal a new level of detail in surface composition. When the M3 science team analyzed data from the instrument, they found the wavelengths of light being absorbed were consistent with the absorption patterns for water molecules and hydroxyl.

“For silicate bodies, such features are typically attributed to water and hydroxyl-bearing materials,” Pieters said. “When we say ‘water on the moon,’ we are not talking about lakes, oceans or even puddles. Water on the moon means molecules of water and hydroxyl that interact with molecules of rock and dust specifically in the top millimeters of the moon’s surface.”

The research was funded by NASA.

Story Source:

Adapted from materials provided by Brown University.

enlarge

These images show a very young lunar crater on the side of the moon that faces away from Earth, as viewed by NASA's Moon Mineralogy Mapper on the Indian Space Research Organization's Chandrayaan-1 spacecraft. Image credit: (Credit: ISRO/NASA/JPL-Caltech/USGS/Brown University)

Related Stories

Finding Water On The Moon Has Major Implications For Human Space Exploration (Sep. 25, 2009) — The discovery of large quantities of water on the moon will have very significant implications for human space exploration, according to a UK space expert. The findings by NASA were reportedly made ...  > read more

Cassini Makes Successful Flight Through Plume Of Saturn's Moon Enceladus (Nov. 10, 2009) — The Cassini spacecraft has weathered the Monday, Nov. 2, flyby of Saturn's moon Enceladus in good health and has been sending images and data of the encounter back to Earth. Cassini had approached ...  > read more

‘Waterless’ Concrete Seen As Building Block On Moon (Oct. 22, 2008) — A new article demonstrates a concept of creating concrete structures on the lunar surface without the use of ...  > read more

Earth Seen By NASA's Moon Mapper On India's Chandrayaan-1 Spacecraft (Aug. 6, 2009) — A new image of Earth taken from 200 kilometers (124 miles) above the lunar surface was taken by the Moon Mineralogy Mapper, one of two NASA instruments onboard the Indian Space Research ...  > read more

Earthshine Reflects Earth's Oceans And Continents From The Dark Side Of The Moon (Apr. 8, 2009) — Researchers have shown for the first time that the difference in reflection of light from the Earth's land masses and oceans can be seen on the dark side of the moon, a phenomenon known as ...  > read more

Search ScienceDaily

Preparing For A Walk On The Moon