INVESTIGATIONS OF EARTHQUAKES ON MARS – INSIGHT MISSION

Abstract

Investigations of the seismicity of Mars, together with other geophysical measurements, contribute to the knowledge of its internal structure. This is important for better understanding of the early evolution of terrestrial planets in the inner Solar System. The NASA InSight mission of 2018 brought to the surface of Mars two seismometers, a heat-flow probe, a magnetometer, meteorological instruments, and radio equipment for the determination of precession and nutation of the rotation axis. Interdisciplinary measurements enabled much better estimations of the thickness and properties of Mars’ crust, mantle and core. In the first ten months of observations 174 marsquakes were detected, with the largest having a magnitude of 4.0. Surprisingly, two different types of seismograms were recorded; they imply a Moon-like crust with high scattering and low attenuation of seismic waves, and an Earth-like mantle with low scattering and high attenuation.