Many seismic events on Mars are not caused by geologic activity, but by meteorite impacts. This is the conclusion reached by the authors of a pair of new papers published in the journal Geophysical Research Letters.
Marsquakes and meteor strikes are common on the Red Planet. Over the past two decades, scientists have scrutinized numerous images and manually identified hundreds of new craters on the Martian surface. And the InSight mission recorded more than 1,300 Marsquakes during its four years of operation. By observing how seismic waves change as they pass through the planet’s crust, mantle and core, scientists have gotten a glimpse into the interior of Mars.
Researchers were also interested in the connection between Marsquakes and meteorite falls. For this purpose, they turned to artificial intelligence, entrusting the task of searching for new craters on spacecraft images to its algorithms. This approach has produced results. The AI was able to detect 123 previously unknown craters. Based on the suspected formation time, magnitude, and distance to InSight, the researchers found a potential link between them and 49 seismic events.
The recent 21-meter crater in the Cerberus Fossae region received the most attention. Scientists believe that the funnel was formed on February 19, 2021. The impact caused seismic vibrations that were recorded by InSight. The distance between the spacecraft and the place where the celestial guest fell was 1640 km.
Thanks to this discovery, scientists realized that seismic waves travel faster and deeper on Mars than previously thought. They figuratively called this phenomenon the seismic highway.
Another important implication of the finding is that scientists will be able to more accurately determine the frequency of meteorites falling on Mars, which could be useful for future Martian missions. According to preliminary estimates, such events occur 1.6 to 2.5 times more frequently than previously thought.
According to ESA
