On September 18, NASA’s InSight lander measured one of the largest, longest-lasting marsquakes the project has ever observed as it celebrated the 1,000th Martian day or sol. The quake was assessed to be a magnitude 4.2 and lasted over an hour and a half.
InSight has identified three big earthquakes in the last month: The mission’s seismometer reported two quakes with magnitudes of 4.2 and 4.1 on August 25. A magnitude 4.2 quake, by comparison, has 5 times the energy of the prior record bearer, a magnitude 3.7 quake discovered in 2019.
Seismic waves are being studied by the mission in order to learn more about Mars’ innards. The waves vary as they travel through the crust, mantle, and core of a planet, allowing scientists to look far beneath the surface. What they discover could help explain how all rocky worlds, notably Earth and its Moon, develop.
Mars’ highly elliptical orbit moved it farther from the Sun, so the quakes may not have been noticed at all if the mission hadn’t taken any action earlier in the year. Because of the lower temperatures, the spacecraft has had to rely more on its heaters to stay warm; this, combined with dust building on InSight’s solar panels, has lowered the lander’s power levels, forcing the mission to preserve energy by momentarily turning off certain sensors.
The scientists deployed InSight’s robotic arm to drip sand close one solar panel in the hopes that as wind gusts moved it across the panel, granules would sweep away some of the dust, keeping the seismometer operational. The idea worked, as the team observed that power levels remained relatively constant over multiple dust-clearing activities. Now that Mars is nearing the Sun once more, power is gradually returning.
InSight’s principal investigator, Bruce Banerdt of NASA’s Jet Propulsion Laboratory situated in Southern California, stated, “If we hadn’t responded fast earlier this year, we would have missed out on some amazing science.” “Mars appears to have offered us something unique with these 2 quakes, which have distinctive properties, even after over two years.”
While scientists are still investigating the September 18 quake, they already understand more about the August 25 quakes: The magnitude 4.2 temblor struck around 8,500 kilometers away from InSight, making it the lander’s farthest temblor ever.
Scientists are trying to figure out where the seismic waves came from and in which direction they traveled. Still, they understand the shaking happened too far away to originate. InSight has identified almost all of its initial huge quakes: Cerberus Fossae, a region about 1,609 kilometers away from where lava may well have flowed within the last few million years. Valles Marineris, which is the monumentally long canyon system that scars the Martian equator, is one particularly intriguing idea. The canyon system’s approximate center is 9,700 kilometers away from InSight.