The three largest earthquakes ever recorded on Mars were detected in the last month by NASA's Insight probe: after having 'dusted' its solar panels to keep the onboard seismometer running, the probe documented two shocks of magnitude 4.2 and 4.1 last August 25, while on September 18 he measured a magnitude of 4.2 which lasted almost an hour and a half.
This was announced by NASA on the blog dedicated to the mission, which was launched in 2018 and has recently celebrated its first thousand Martian days.
The data of the earthquake of September 18 are still under study, while several details relating to the tremors of August 25 are already known. The 4.2 magnitude event occurred about 8,500 kilometers away from Insight, making it the farthest the spacecraft has detected so far. NASA experts are trying to identify the exact point from which the seismic waves started and the direction they followed: what is certain is that the event took place too far to have originated in the Cerberus Fossae region like other major earthquakes. that preceded it. A very suggestive hypothesis is that the earthquake started from the great Valles Marineris canyon which marks the Martian equator. The earthquake was characterized by slow, low-frequency vibrations, while the magnitude 4 event.1 recorded on the same day had faster, higher frequency vibrations originating about 925 kilometers away from the spacecraft. Having recorded earthquakes so different from each other will allow us to acquire more information on the internal structure of the planet.