The seismometer installed on Mars has detected the first seismic tremor on the red planet.
It was last April 6 and a soft but distinctive seismic signal was detected, similar to the earthquakes detected on the surface of the Moon by the Apollo missions. It is the first earthquake that seems to come from the interior of Mars, unlike the tremors produced by the wind, although scientists are still not entirely sure of its cause.
The seismic event is too small to provide useful data about the Martian interior, one of InSight’s main goals. Such an earthquake would not even have been recorded on Earth, but the Martian surface is nearly dead, allowing highly sensitive seismometer sensors to detect this faint noise.
Several features of the event fit the profile of moon earthquakes. NASA astronauts measured thousands of earthquakes as they explored the Moon between 1969 and 1972, revealing that it was still geologically active. Different materials can change the speed of seismic waves or reflect them, allowing scientists to learn about the Moon’s interior and the size of its nucleus.
This research allowed a better understanding of the impact between the Earth and the proto-Moon, and how the Moon later formed from the disc of debris. With the SEIS seismometer, scientists will be able to collect similar data on Mars and obtain deeper information on the formation of rocky planets.