Crystal clues on Mars point to watery and possibly life-supporting past

(Press-News.org) A QUT-led study analysing data from NASA’s Perseverance rover has uncovered compelling evidence of multiple mineral-forming events just beneath the Martian surface – findings that bring scientists one step closer to answering the profound question: did life ever exist on Mars?

The QUT research team led by Dr Michael Jones, from the Central Analytical Research Facility and the School of Chemistry and Physics, includes Associate Professor David Flannery, Associate Professor Christoph Schrank, Brendan Orenstein and Peter Nemere, together with researchers from North America and Europe.

The findings were published in the prestigious journal Science Advances.

“Sulphate minerals exist with different amounts of water in most regions on Mars and allow us to understand how water moved around the planet, which is key to understanding its past habitability,” Dr Jones said.

“However, we don’t yet fully understand how or when these minerals formed. Our team found a way to measure the internal crystal structure of these minerals directly in the rock, which had thought to be impossible on the surface of Mars.”

The team adapted a new analytical method called X-ray Backscatter Diffraction Mapping (XBDM) developed by Dr Jones and Professor Schrank at the Australian Synchrotron to Perseverance’s onboard PIXL instrument developed by QUT alumna Abigail Allwood.

This allowed the team to determine the orientation of the crystal structures, essentially providing a fingerprint of how and when they grew, and what the environment on Mars was like at that time.

Two separate generations of calcium-sulphate minerals were uncovered at Hogwallow Flats and Yori Pass in the Shenandoah formation, part of the sedimentary fan in Jezero crater: one formed just beneath the surface and the other formed deeper underground, at least 80 meters down.

“This discovery highlights the diversity of environments that existed in the Shenandoah formation’s history — indicating multiple potential windows when life might have been possible on Mars,” Dr Jones said.

Since its landing in Jezero Crater in February 2021, the Perseverance rover has been exploring a wide variety of Martian rock types, from ancient lava flows to sedimentary layers left behind by a long-vanished lake and river delta.

One of its key mission goals is to study environments that could have supported microbial life – and collect samples that might someday be returned to Earth.

The QUT research team is part of the multidisciplinary QUT Planetary Surface Exploration Research Group which focuses on interplanetary science and is actively involved in projects within NASA and the Australian Space Agency.

Professor Flannery, long-term planner for the NASA Perseverance mission, said QUT is at the forefront of planetary science in Australia.

“Experience gained by QUT researchers exposed to the cutting edge of the robotics, automation, data science and astrobiology fields has the potential to kick start Australia’s space industry,” he said.

Read the full paper, In-situ crystallographic mapping constrains sulphate precipitation and timing in Jezero crater, Mars, published in Science Advances online.

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