“The Big One”: The Most Powerful Marsquake Ever Detected
A new paper explains how the largest recorded seismic event on Mars provided evidence for the release of stress within the Martian crust.
The ground shakes. Paintings tilt. Walls crack. Rubble may fall. On Earth, we understand how and where these events happen due to the discovery of plate tectonics — the continental crust’s creation, movement, and destruction. However, when astronauts placed seismometers on the lunar surface during NASA’s Apollo mission era, those instruments recorded quakes on the Moon. In the 1970s, the Viking landers also recorded quakes on the surface of Mars. Since neither of these worlds has plate tectonics, scientists set about collecting more data to understand the phenomena, which led to the recent NASA InSight lander. Now, a new paper in Geophysical Research Letters explains how the largest recorded seismic event on Mars provided evidence for a different sort of tectonic origin — the release of stress within the Martian crust.
On Wednesday, May 4, 2022, InSight recorded a record-breaking magnitude 4.7 marsquake with an epicenter about 2,200 kilometers away from the lander. The resulting tremors shook the planet for the next six hours. The event was large, but scientists had no reason to believe the cause…