Marsquakes! For Science!

In principle, at least, the use of seismic – earthquake – waves to understand the interior of a planet is less complicated than it first seems. You’re probably familiar with bats’ use of echolocation to navigate the night skies: they emit high-pitched squeaks, and then use the reflections, the echoes, to navigate and find prey. Seismic reflection is much the same, except the equivalent of the bat “squeak” is a remote earthquake, and the reflections come for the differentiated layers of the planet’s structure.

Geologists and geophysicists have been using seismology to analyze the Earth’s structure for years. The same technique has been applied to Mars.

In February 2019, Mars Insight went on-line, a sophisticated seismometer placed on Elysium Planitia near the Martian equator. Since, Mars Insight has tracked Marsquakes and the pressure and shear waves those quakes generate as they reflect and refract…