Meteorite from Mars shows traces of water – but no life

NASA’s Parachute spacecraft landed on the dusty surface of Mars in February 2021. For several years, the rover will travel around the planet and take samples to try to answer the question of life on Mars. NASA is expected to ship samples home only around 2030. But today, material from Mars is being studied here on Earth, in the form of meteorites. In a new study, an international research team, led by Lund University, has studied a meteorite that is about 1.3 billion years old through the Advanced Survey.

Since water is central to the question of whether life exists on Mars, we wanted to investigate how much the meteorite interacted with water when it was still part of Martian rock, says Josephine Martell, a doctoral student in geology at Lund University.

X-rays show hydrogen inside the meteorite

To answer the question of whether there is any major hydrothermal system, which is often a favorable environment for the occurrence of life, the researchers immediately used neutron tomography and X-rays. X-ray computed tomography is a common way to examine the body 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 thus find out where the hydrogen is in the meteorite.

The element hydrogen (H) is always of interest when scientists study material from Mars, because water (H2O) is a prerequisite for life as we know it. The new study shows that a fairly small portion of the sample appears to have reacted with the water, so it may not have been a large hydrothermal system that did the conversion.

The most likely explanation is that the reaction occurred after small accumulations of underground ice melted during a meteorite impact about 630 million years ago. Of course, this says nothing about the possibility that life may have existed elsewhere on Mars, or that there may have been life at other times, says Josephine Martell.

Want to study samples from Mars?

The researchers hope that the results of their study will be useful when, around 2030, NASA brings the first samples from Mars. There are several indications that current neutron tomography and X-ray technology will be useful in these future studies.

It would be interesting if we had the opportunity to study these Martian samples at the European Spallation Source (ESS) research facility in Lund, which would then be the world’s most powerful neutron source, says Josephine Martell.

Scientific study:

Scale exploration of the Mars hydrothermal system using X-ray and neutron tomographyscience progress .

Contact:

Josephine Martell, PhD student, Department of Geology, [email protected]

In addition to Lund University, the following institutions and institutions of higher education were involved in the work:
University of Glasgow, University of Sydney, University of Oxford, Institute for Advanced Neutron and X-ray Science (LINXS), University of Copenhagen, Natural History Museum Denmark, European Spallation Source (ESS), University of Malmö, Laue Langevin Institute, Grenoble Alps University.