A strong quake in the last year of the NASA Mars InSight mission, enabled researchers at ETH Zurich to determine the global thickness and density of the planet's crust. On average, the Martian crust much thicker than the Earth's or the moon's crust, and the planet's main source of heat is radioactive.
This article has been reviewed according to Science X's editorial process and policies . Editors have highlighted the following attributes while ensuring the content's credibility: Topographic map of the Martian surface (l.) and representation of the crust thickness (r.). Credit: MOLA Science Team / Doyeon Kim, ETH Zurich After more than three years of daily monitoring and with the power levels decreasing on InSight's seismometer, researchers were rewarded with data from a sizeable Marsquake in May 2022. The surface waves observed from this estimated 4.6 magnitude quake not only traveled from the quake's source to the measuring station, they also continued to travel around the entire planet several times. This data not only provided information about specific areas of Mars, but also enabled a global view of the planet. "From this quake, the largest quake recorded during the entire InSight mission, we observed surface waves that circled Mars up to three times," says Doyeon Kim, seismologist and lead author of a study just published in the journal, Geophysical Research Letters. In order to gain information about the structure that the waves passed through, the researchers measured how fast these waves propagate at different frequencies. These seismic velocities provide insights into the interior structure at different depths. Previously, observed surface waves from the two large meteorite impacts also allowed regional findings along their specific propagation paths. "Now, we have seismic observations that represent the global structure," says Kim. Comparing data from Mars with that of the Earth and the moon Combining their newly obtained results with existing data on the…