BROCK UNIVERSITY NEWS RELEASE ******************** Mariek Schmidt is among a team of scientists from around the world examining rocks on Mars in hopes of learn more about the history of the red planet. A participating scientist on NASA’s Mars Perseverance rover, the Brock University Earth Sciences professor played a key role in a research study released Thursday, Aug. 25, that outlined one of the first surveys of its kind conducted after it landed rover in Jezero Crater in February. 2021. Also assisting in the study, which was led by Yang Liu at NASA’s Jet Propulsion Lab, was Brock postdoctoral fellow Tanya Kizovski. As part of the Mars mission, Schmidt worked with other scientists to help guide the use of the rover’s instruments for research and data collection. Her focus was on the Planetary Instrument for X-Ray Lithochemistry (PIXL), an X-ray fluorescence spectrometer used to determine the fine-scale elemental composition of Martian surface materials. “One of the big unknowns when we landed in Jezero Crater was the origin of a particular rock unit,” says Schmidt, describing a massive rock mass detectable from orbit that covers about 70,000 square kilometers of the planet’s surface. “Once PIXL was able to analyze it, we were able to determine its origin.” The rock contains a significant amount of olivine—a mineral rich in iron and magnesium—as well as carbonate, a carbon-bearing compound that “may have some biosignature potential,” says Schmidt. Using PIXL, the researchers determined that olivine likely formed deep underground from slowly cooling magma — or molten rock — before being exposed over time by weathering. They were also able to see how the various minerals within the igneous rock were related to each other. Olivine minerals, for example, were well-formed crystals that hadn’t been eroded by wind or water, Schmidt says. Because olivine is dense, the crystals settle downward, accumulating on the floor of a magma chamber or lava flow. A second mineral arrived later, which was also high temperature and filled the spaces around the olivine. Schmidt called the discovery “eye-opening.” “This is a view that we’ve never had before on Mars to be able to do this kind of testing,” he says. “We were able to show that, at least in this particular place, the widespread unit is an igneous rock.” The rock type, he adds, is similar to that of a Martian meteorite found on Earth called chassignite. “We’re able to take a lot of pictures from Mars’ orbit, but ground truthing (validating data on the ground) is really critical to being able to understand the geology of the planet, and this shows that,” says Schmidt. “We don’t find a rock where life once existed, but we think this is an important rock unit for understanding the history of Mars.” Samples from the rock unit examined in the study were collected on Mars, with the goal of seeing them return to Earth around 2034. “It’s amazing to be a part of this discovery — to see rocks and interpret rocks that have never been seen before.” , says Schmidt. “Basically as a scientist, it’s gratifying to be able to see a rock that no one else has seen before and say, ‘I know exactly what that is.’ The research team’s study, “A cumulus olivine outcrop on the floor of Jezero Crater, Mars,” was one of a series of research papers released Thursday in connection with the Perseverance mission.
