By Katherine Kornei
Martians! If you’re out there — duck and cover!
On May 4, a monster Marsquake shook the Red Planet. And it was a doozy. The roughly magnitude 5 quake rocked and rolled for more than six hours. It’s not the first quake seen on Mars. But it’s the largest detected to date. In fact, it let loose more than 10 times as much energy as the previous record-holding quake.
NASA’s InSight lander recorded the new finding. A quake this strong would be considered a medium-size one on Earth. However, it’s near the top of what scientists had hoped InSight might see, according to NASA’s Jet Propulsion Laboratory in Pasadena, Calif.
The lander has been listening for quakes since it touched down on Mars in 2018. Marsquakes happen when the planet cools and contracts. That sends seismic waves rumbling through the ground. This quake probably kicked off near the Cerberus Fossae region on Mars. That’s more than 1,000 kilometers (620 miles) from InSight.
It makes sense that the ground would be shifting there, says Philippe Lognonné. Cerberus Fossae is known for its cracked surface and frequent rockfalls. “It’s an ancient volcanic bulge,” he notes. He’s the lead scientist on InSight’s seismometer. That’s an instrument that measures tremors. As a geophysicist, Lognonné studies how energy and forces shape planets. He works at the Institut de Physique du Globe de Paris in France.
Earthquakes help us understand the structure of the layers within our planet. In a similar way, Marsquakes can provide a look below the surface of Mars. And a lot can be learned from this whopper of a quake, says Lognonné. “The signal is so good, we’ll be able to work on the details.”