GLASGOW & WEST SCOTLAND
23 April 2012 Last updated at 10:19 GMT
Martian meteorite tested at Glasgow University Academics in Scotland are to test a rare meteorite from Mars to determine how long it spent in space.
The meteorite, named Tissint after the area of Morocco where it landed last year, may have drifted in space for hundreds of thousands of years.
A 0.2-gram fragment will be tested at the Scottish Universities Environmental Research Centre in East Kilbride.
Of the 41,000 meteorites which are known to have fallen to Earth, just 61 have originated from Mars.
Martian meteorites which have been discovered on Earth each come from three different areas of the planet and are classified as nakhlites, shergottites and chassignites.
Space ages
From chemical analysis, it is believed that all the nakhlites were ejected from Mars about 10 million years ago.
Shergottites and chassignites, however, have a range of space ages, indicating that Mars has been impacted several times.
The fragment of rock being tested in Scotland comes from a 1kg piece of the Tissint meteorite – a shergottite – which was acquired by the Natural History Museum in London.
Glasgow University academic Dr Fin Stuart will be leading the Tissint analysis.
He said: “As meteorites travel through space, they are bombarded with high-energy cosmic radiation, which our atmosphere shields us from here on Earth.
“The radiation explodes some atoms in the meteorite, creating ‘daughter’ atoms. The new atoms are known as cosmogenic isotopes.
“They are very rare on Earth and are one of the telltale fingerprints which show an object has spent time in space.”
Dr Stuart said his team would use “a high-precision mass spectrometer to measure the cosmogenic isotopes of the gases helium, neon and argon in Tissint”.
He added: “From these measurements we can determine how long the meteorite was exposed to cosmic radiation in space, and thus how long ago it left Mars.
“It requires measuring a few million atoms, but we’re hopeful that we’ll be able to get a much clearer idea than we currently have of how long Tissint, and the shergottite meteorite group as a whole, spent in space before reaching Earth.”
The Scottish Universities Environmental Research Centre is a collaboration between Glasgow and Edinburgh Universities.
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