Chunks of Mars rocks could be on their way to Earth, here's how

By subjecting rocks containing plagioclase, a common Martian mineral, to intense pressure using a state-of-the-art blast gun, the researchers were able to observe and analyze the transformations that occur during ejection.

Through these laboratory simulations, the researchers discovered that the force required to launch Martian rocks into space is significantly lower than initially thought. Previous experiments had suggested that plagioclase transformed into a glassy substance known as maskelynite at a shock pressure of 30 gigapascals (GPa). However, the new research indicates that this transition occurs at around 20 GPa, challenging our previous understanding of the launch dynamics.

This revised understanding of the force required for ejection has profound implications for our knowledge of Martian impact events.

It suggests that even moderate impacts on Mars can propel rocks into space, increasing the likelihood of Martian meteorites reaching Earth. This opens up exciting possibilities for discovering more Martian meteorites and gaining valuable insights into Mars' geological activity.

Unlocking Mars' geological history

The findings of this study have crucial implications for our understanding of Mars' geological history. Martian meteorites offer a unique window into the Red Planet's past, offering valuable insights into its formation, volcanic activity, and potential for supporting life.

By accurately characterizing the forces involved in the ejection of Martian rocks, scientists can now refine their search for meteorites and trace them back to their source impact craters on Mars.

Pinpointing the exact locations of Martian impact craters is crucial for unraveling Mars' geological timeline. With a more precise understanding of the forces involved in launching meteorites, scientists can better identify the specific craters responsible for ejecting these intriguing rocks. This knowledge allows them to reconstruct the sequence of impact events on Mars, shedding light on its geological evolution over billions of years.

The study is described in a paper appearing in the journal Science Advances. 

Study Abstract:

Diaplectic feldspathic glass, commonly known as maskelynite, is a widely used impact indicator, notably for shergottites, whose shock conditions are keys to their geochemistry and launch mechanism. However, classic reverberating shock recovery experiments show maskelynitization at higher shock pressures (>30 gigapascals) than the stability field of the high-pressure minerals found in many shergottites (15 to 25 gigapascals). Most likely, differences between experimental loading paths and those appropriate for martian impacts have created this ambiguity in shergottite shock histories. Shock reverberation yields lower temperature and deviatoric stress than single-shock planetary impacts at equivalent pressure. We report the Hugoniot equation of state of a martian analog basalt and single-shock recovery experiments, indicating partial-to-complete maskelynitization at 17 to 22 gigapascals, consistent with the high-pressure minerals in maskelynitized shergottites. This pressure explains the presence of intact magmatic accessory minerals, used for geochronology in shergottites, and offers a new pressure-time profile for modeling shergottite launch, likely requiring greater origin depth.