Why Is NASA Looking for ‚Marsquakes‘?

Artist’s rendition of the InSight lander on the surface of Mars. Credit: NASA
Scientists are keeping their fingers crossed for numerous quakes — marsquakes, that is.

By Yasemin Saplakoglu | SPACE.com

Nov. 26, NASA’s newest Mars exploration mission, called the Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) mission, is scheduled to touch down on the surface of the Red Planet. With a design inspired by the older Mars lander Phoenix, this next-generation machine will extend its robot arms and place a seismometer — a device that measures quakes — onto the surface of Mars. If all goes well, for two Earth years (one Mars year), it will listen for vibrations that happen beneath the surface of the planet, to answer some fundamental questions about how rocky planets, including our own, formed. [Mars InSight Photos: A Timeline to Landing on the Red Planet]

But what are marsquakes, and why are NASA scientists hunting for them?

Marsquakes, just like earthquakes, are vibrations that move through the ground. But the way these quakes form on the Red Planet may be fundamentally different from how they form on Earth. And it turns out that these differences could help scientists better understand what early Earth looked like.

For the most part, earthquakes on our planet occur because of plate tectonics, the mechanics that occur as the plates that make up Earth’s outer shell glide over the mantle, Earth’s rocky innards. These tectonic plates are constantly moving — roughly between 2 and 4 inches (5 to 10 centimeters) each year, according to Britannica — bumping into and slipping past one another. Sometimes, when a plate is moving past another plate, its rough edge gets stuck and stops, while the rest of the plate continues to move. Because that part of the plate is stuck, it stores up the energy it would normally use to move, eventually catching up to the rest of the plate and releasing all the energy as seismic waves — causing shaking, according to the U.S. Geological Survey (USGS).

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