The strongest earthquake to hit Mars was not caused by an asteroid impact, but by tectonic forces inside the planet, scientists said on Tuesday, October 17. New results show that the Red Planet is more seismically active than before.

On May 4, 2022, NASA’s decommissioned InSight lander recorded a magnitude 4.7 earthquake, five times stronger than the previous record holder of magnitude 4.2 measured by InSight in 2021. Unlike most aftershocks that stop within an hour, the May 2022 Echo Quake lasted six hours, making it the strongest and longest earthquake ever recorded on another planet.

Since landing on Mars’ Elysium Planitia in November 2018, Insight has recorded more than 1,300 aftershocks, at least eight of which were linked to asteroid impacts. The strong earthquake signal measured by a sensitive seismometer on the lander in May 2022 was similar to other earthquakes caused by asteroid impacts; For this reason, scientists began looking for a new 300-meter-wide crater on Mars and a dust cloud that might emerge. right after the asteroid hit. According to the scientists, teams from India, China, Europe and the United Arab Emirates searched for these indicators using suitable orbits around Mars, but they were never found. Therefore, after months of research, scientists concluded that the earthquake was of tectonic origin.

Conventional belief is that, unlike Earth, Mars is too small and too cold for tectonic processes. Earth’s tectonic plates (massive, irregularly shaped rocks whose boundaries are buried beneath the oceans) move in response to forces in the mantle (the layer between the crust and core), often leading to landslides and earthquakes. However, since the surface of Mars is not crushed like the surface of the Earth, it is believed that plate tectonics does not occur on the Red Planet.

The earthquake detected by InSight was likely caused by the release of billions of pounds of stress in the evolving Martian crust as different parts of the planet cooled and contracted at different rates, according to a new study.

“We still don’t fully understand why some parts of the planet appear to be more stressed than others, but results like this help us investigate further,” said Benjamin Fernando, a postdoctoral researcher at the University of Oxford in the United Kingdom. expression. “One day, this information could help us understand where it would be safe for humans to live on Mars and where we should avoid!” Source