MessageToEagle.com - Scientists, using data from NASA's Moon Mineralogy Mapper (M3) have detected
magmatic water — water that originates from deep within the Moon's interior — on
the surface of the Moon.
"For many years, researchers believed that the rocks from the Moon were ‘bone dry' and that any water detected
in the Apollo samples had to be contamination from Earth," said Klima.
The lunar impact crater Bullialdus
"About five years ago, new laboratory techniques used to investigate lunar samples revealed that the interior
of the Moon is not as dry as we previously thought.
Around the same time, data from orbital spacecraft detected
water on the lunar surface, which is thought to be a thin layer formed from solar wind hitting the lunar surface."
"This surficial water unfortunately did not give us any information about the magmatic water that exists deeper
within the lunar crust and mantle, but we were able to identify the rock types in and around Bullialdus crater,"
said co-author Justin Hagerty, of the U.S. Geological Survey.
"Such studies can help us understand how the surficial water originated and where it might exist in the lunar mantle."
"It's within 25 degrees latitude of the equator and so not in a favorable location for
the solar wind to produce significant surface water," Klima explained.
"The rocks in the central peak of the crater are of a type called norite that usually crystallizes when magma
ascends but gets trapped underground instead of erupting at the surface as lava. Bullialdus crater is not the only
location where this rock type is found, but the exposure of these rocks combined with a generally low regional
water abundance enabled us to quantify the amount of internal water in these rocks."
Click on image to enlarge
Scientists have learned that the lunar impact crater Bullialdus has significantly more hydroxyl — a molecule consisting of one oxygen atom and one hydrogen atom — compared to its surroundings. Pictured
is the central peak of Bullialdus rising above the crater floor with the crater wall in the background.
Image Credit: NASA/GSFC/Arizona State University
After examining the M3 data, Klima and her colleagues found that the crater has significantly more hydroxyl —
a molecule consisting of one oxygen atom and one hydrogen atom — compared to its surroundings.
"The hydroxyl absorption features were consistent with hydroxyl bound to magmatic minerals that were excavated
from depth by the impact that formed Bullialdus crater," Klima writes.
The internal magmatic water provides information about the Moon's volcanic processes and internal composition,
The detection of internal water from orbit means that scientists can begin to test some of the findings from sample
studies in a broader context, including in regions that are far from where the Apollo sites are clustered on the
near side of the Moon.
"Now we need to look elsewhere on the Moon and try to test our findings about the relationship
between the incompatible trace elements (e.g., thorium and uranium) and the hydroxyl signature," Klima said.
"In some cases this will involve accounting for the surface water that is likely produced by interactions with
the solar wind, so it will require integration of data from many orbital missions."