What InSight found out was that Mars has a rather thin and layered crust. Under that lies a thick mantle and that literal hell of a core. The SEIS (Seismic Experiment for Interior Structure) data went into such depth that researchers actually published three studies in
Science one each for the crust, mantle and core and a fourth that goes into the overall composition of Martian innards.
“Seismic waves are a great tool to tell you about the interior of a planet,” researcher Bridgitte Knapmeyer-Enddrun, who led the crust study, tells SYFY WIRE. “They travel through the planet and on their way from the source of the quake to the seismometer, where they are recorded, and pick up information on the materials they are traveling through.