A research team led by Lund University in Sweden has studied a meteorite from Mars using neutron and X-ray tomography. The technology, which will likely be used when NASA examines samples from the Red Planet in 2030, showed that the meteorite had limited exposure to water, thus making life unlikely at that exact time and place.
In a cloud of smoke, NASA’s Perseverance spacecraft parachutes onto the dusty surface of Mars in February 2021. For several years, the vehicle will skid and collect samples in an attempt to answer the question posed by David Bowie in Life on Mars in 1971. It wasn’t until around 2030 that Nasa actually intended to return the samples to Earth, but material from Mars was already being studied – in the form of meteorites. In a new study published in Scientists progressan international research team has studied a meteorite about 1.3 billion years old using advanced scanning.
“Since water is central to the question of whether life ever existed on Mars, we wanted to investigate how much of the meteorite reacted with water while it was still part of the bedrock of Mars,” explains Josefin Martell, PhD student in geology at Lund University.
To answer the question of whether there was a major hydrothermal system, which is usually a supportive environment for life, researchers used neutron and X-ray tomography. X-ray tomography is a common method to examine an object without damaging it. Neutron tomography was used because neutrons are very sensitive to hydrogen.
This means that if a mineral contains hydrogen, it is possible to study it in three dimensions and see where the hydrogen is in the meteorite. Hydrogen (H) is always of interest when scientists study materials from Mars because water (H2O) is a prerequisite for life as we know it. The results show that a fairly small portion of the sample appears to have reacted with water, so it was probably not a large hydrothermal system that caused the alteration.
“A more likely explanation is that the reaction took place after small accumulations of underground ice melted during a meteorite impact about 630 million years ago. couldn’t have existed anywhere else on Mars, or that there wouldn’t have been life at other times,” says Josefin Martell.
The researchers hope the results of their study will be useful when NASA brings back the first samples from Mars around 2030, and there are many reasons to believe that current technology with neutron and X-ray tomography will be useful when that happens. will produce.
“It would be fun if we had the opportunity to study these samples at the European Spallation Source, ESS research center in Lund, which will then be the most powerful neutron source in the world”, concludes Josefin Martell.