NASA’s InSight lander has just detected the largest Mars quake yet. With an estimated magnitude of 5, this is over six times more energetic than the previous record holder, a 4.2 magnitude tremor that shook the ground for 90 minutes back in September 2021.
This new one was not quite as long, but was certainly longer than any quakes on our planet, being detectable for about 30 minutes. The new quake is mid-size compared to Earth’s own but for Mars, which hasn’t got plate tectonics, it's excitingly close to the maximum theoretical limit.
InSight has been using the more than 1,300 Marsquakes it has detected as a sonogram for the interior of the planet. As seismic waves move through Mars, they are changed by the different layers. By studying those changes, it is possible to understand what goes on beneath the surface of the Red Planet. A quake this big will provide even better data to understand the interior of Mars.
“Since we set our seismometer down in December 2018, we’ve been waiting for ‘the big one,’” Bruce Banerdt, InSight’s principal investigator at NASA’s Jet Propulsion Laboratory, said in a statement. “This quake is sure to provide a view into the planet like no other. Scientists will be analyzing this data to learn new things about Mars for years to come.”
Quakes, whether on Earth, Mars, or even the Moon, are shaking off the world’s surface due to a build-up of tension. On Earth, this is due to the tectonic plates constantly pushing against each other, as they float on the ocean of magma underneath. But Earth is unique in that feature. So without tectonics, otherworldly quakes tend to be less powerful and more prolonged.
Marsquakes are believed to be caused by the Martian interior cooling. This process, common in terrestrial worlds, causes materials to contract as they get older. That’s the mechanism that builds up tension on Mars which is occasionally released through the fracturing of the crust. The team will need to conduct further studies to better characterize the event.
It is uncertain if a larger quake will be detected, and not just because they are rare. InSight’s mission was extended until December but the NASA lander is currently battling the elements. Winter is coming in its hemisphere and the higher dustiness of the Martian atmosphere has dramatically reduced the amount of sunlight that gets to its solar panels. On May 7, the lander entered safe mode suspending all but essential functions because of this. C'mon InSight, we're rooting for you.