Mars is more seismically active than previously thought. This is the conclusion of a group of scientists who analysed a powerful quake that struck the Red Planet last year. It was the strongest-ever quake on Mars and it arose not because an asteroid crashed into the planet but because of the tectonic forces within it, the scientists have been quoted as saying by space.com. The quake was recorded on May 4, 2022, by InSight, NASA's now-retired lander. The magnitude was 4.7 - five times stronger than the previous record holder - the outlet further said.
It was also the longest recorded quake since the reverberations continued for six hours.
A research describing the discovery in detail has been published in the journal Geophysical Research Letters.
InSight landed on Mars in November 2018 and recorded over 1,300 Marsquakes, said the space.com report. Eight of those were traced to asteroid impacts.
Similar thing was believed to be behind the May 2022 quake too, which is why teams from India, China, Europe and the United Arab Emirates searched for these indicators using their respective orbiters circling Mars, but could never find any of an asteroid impact. So, after months of searching, scientists concluded that the quake was tectonic in origin.
This particular discovery sheds light on the evolution of Mars, which is considered too small and too cold to host tectonic processes like Earth. The Martian surface is not broken in same way as Earth's is, so plate tectonics are not believed to occur on the Red Planet.
However, the new study shows Mars the quake was caused by the release of billion-year-old stress within Mars' crust, which formed and evolved due to various parts of the planet cooling and shrinking at different rates.
"We still do not fully understand why some parts of the planet seem to have higher stresses than others, but results like these help us to investigate further," Benjamin Fernando, a postdoctoral fellow at the University of Oxford in the UK, was quoted as saying by space.com.
Mr Fernando said this information can one day tell us where humans can settle on Mars and which areas to avoid.
