[FPSPACE] Fw: NASA: Water Content of Moon's Interior Underestimated

[LARRY KLAES]

Sent via BlackBerry by AT&T

-----Original Message-----
From: "AAS Press Officer Dr. Rick Fienberg" <rick.fienberg at aas.org>
Date: Mon, 14 Jun 2010 20:33:43 
To: <Rick.Fienberg at aas.org>
Subject: NASA: Water Content of Moon's Interior Underestimated

THE FOLLOWING RELEASE WAS RECEIVED FROM NASA HEADQUARTERS IN
 WASHINGTON, DC, AND IS FORWARDED FOR YOUR INFORMATION. (FORWARDING
 DOES NOT IMPLY ENDORSEMENT BY THE AMERICAN ASTRONOMICAL SOCIETY.) Rick
 Fienberg, AAS Press Officer: rick.fienberg at aas.org, +1 202-328-2010
 x116.
 
 June 14, 2010
 
 Contacts:
 Dwayne Brown
 Headquarters, Washington
 +1 202-358-1726
 dwayne.c.brown at nasa.gov
 
 Tina McDowell
 Carnegie Institution of Washington
 +1 202-939-1120
 tmcdowell at ciw.edu
 
 RESEARCH SUGGESTS WATER CONTENT
 OF MOON INTERIOR UNDERESTIMATED
 
 NASA-funded scientists estimate from recent research that the volume
 of water molecules locked inside minerals in the Moon's interior could
 exceed the amount of water in the Great Lakes here on Earth.
 
 Scientists at the Carnegie Institution's Geophysical Laboratory in
 Washington, along with other scientists across the nation, determined
 that the water was likely present very early in the Moon's formation
 history as hot magma started to cool and crystallize. This finding
 means water is native to the Moon.
 
 "For over 40 years we thought the Moon was dry," said Francis McCubbin
 of Carnegie and lead author of the report published in Monday's Online
 Early Edition of the Proceedings of the National Academy of Sciences.
 "In our study we looked at hydroxyl, a compound with an oxygen atom
 bound with hydrogen, and apatite, a water-bearing mineral in the
 assemblage of minerals we examined in two Apollo samples and a lunar
 meteorite."
 
 McCubbin's team utilized tests which detect elements in the parts per
 billion range. Combining their measurements with models that
 characterize how the material crystallized as the Moon cooled during
 formation, they found that the minimum water content ranged from 64
 parts per billion to 5 parts per million. The result is at least two
 orders of magnitude greater than previous results from lunar samples
 that estimated water content of the Moon to be less than 1 part per
 billion.
 
 "In this case, when we talk about water on the Moon, we mean water in
 the structural form hydroxyl," said Jim Green, director of the
 Planetary Science Division at NASA Headquarters in Washington. "This
 is a very minor component of the rocks that make up the lunar
 interior."
 
 The origin of the Moon is now commonly believed to be the result of a
 Mars-size object that impacted the Earth 4.5 billion years ago. This
 impact put a large amount of material into Earth's orbit that
 ultimately compacted to form the Moon. The lunar magma ocean that is
 thought to have formed at some point during the compacting process,
 began to cool. During this cooling, water either escaped or was
 preserved as hydroxyl molecules in the crystallizing minerals.
 
 Previous studies found evidence of water both on the lunar surface and
 inside the Moon by using, respectively, remote sensing data from the
 Indian spacecraft Chandrayaan-1 and other lunar sample analysis.
 
 Carnegie researchers looked within crystalline rocks called KREEP (K
 for potassium; REE, for rare Earth elements; and P for phosphorus).
 These rocks are a component of some lunar impact melt and basaltic
 rocks.
 
 "Since water is insoluble in the main silicates that crystallized, we
 believed that it should have concentrated in those rocks," said Andrew
 Steele of Carnegie and co-author of the report. "That's why we
 selected KREEP to analyze."
 
 The identification of water from multiple types of lunar rocks that
 display a range of incompatible trace element signatures indicates
 that water may be at low concentrations but ubiquitous within the
 Moon's interior, potentially as early as the time of lunar formation
 and magma ocean crystallization.
 
 "It is gratifying to see this proof of the hydroxyl contents in lunar
 apatite," said lunar scientist Bradley Jolliff of Washington
 University in St. Louis. "The concentrations are very low and,
 accordingly, they have been until recently nearly impossible to
 detect. We can now finally begin to consider the implications -- and
 the origin -- of water in the interior of the Moon."
 
                            # # #
 
 The research was funded by the NASA Astrobiology, Mars Fundamental
 Research, and the Lunar Advanced Science and Exploration Research
 programs in NASA's Planetary Division in Washington.
 
 ------------------------------------------------------------------------
 If you do not wish to receive press releases that are forwarded to the
 news media by the American Astronomical Society, please unsubscribe by
 replying accordingly to any incoming press release, or send e-mail to
 rick.fienberg at aas.org. Requests for referrals to experts on astronomy
 and space science should be sent to the same address. Rick Fienberg,
 AAS Press Officer, +1 202-328-2010 x116.