New technique to unveil age of Moon rocks

Researchers are developing instruments and methods for measuring the age of rocks encountered during space missions to the Moon and planets.
Many of the techniques used to date rocks on Earth are not practical in spaceflight, but a technique called laser ablation resonance ionisation mass spectrometry can avoid the need for sophisticated sample preparation.
A team led by Dr F Scott Anderson from Southwest Research Institute, Boulder, Colorado, US, has now demonstrated that this technique can successfully date an Earth rock - the Duluth Gabbro - that is analogous to the rocks that cover one-third of the lunar nearside.
Their results imply that events from Solar System history that are recorded on much of the visible face of the Moon can one day be dated directly by instruments aboard a lunar lander.

"We can see cratered terrains on the Moon whose ages we don't know within a billion years," said Anderson.
"Ages of lunar terrains are the linchpin for understanding the sequence of planetary-scale events from Mercury to Mars, so filling this gap in our understanding of the Moon will help us correct or re-write the history of volcanism, planetary evolution, water, and life in the Solar System," said Anderson.

Dating the Duluth Gabbro was approximately 30 times more analytically challenging than our previous experiment, dating the Martian meteorite Zagami, noted co-author Dr Jonathan Levine from the Department of Physics and Astronomy, Colgate University, Hamilton, New York.

"We are now continuing to analyse planetary samples of increasing complexity," he said.
The research was published in the journal Rapid Communications in Mass Spectrometry.