Mars is not as seismically active as Earth but there are still things going on. NASA’s InSight is providing invaluable data about the interior of the planet and scientists now report that the lander has spotted two new significant quakes on Mars.
These events come from the same region where the strongest quakes previously registered came from: Cereberus Fossae. The previous two marsquakes had a magnitude of 3.6 and 3.5 while the two new ones are reported to be 3.3 and 3.1. The tremors strongly suggest that the region is seismically active. The quakes were recorded on March 7 and March 18.
InSight has so far recorded more than 500 marsquakes but most of them are very weak, longer-lasting, and scattered, making them similar to moonquakes. Earthquakes instead travel more directly into the planet, they are a lot stronger and attenuated by more factors in the Earth’s interior.
“Over the course of the mission, we’ve seen two different types of marsquakes: one that is more ‘Moon-like’ and the other, more ‘Earth-like,’” Taichi Kawamura of France’s Institut de Physique du Globe de Paris, said in a statement. “Interestingly, all four of these larger quakes, which come from Cerberus Fossae, are ‘Earth-like.’”
It’s been a while since we had reports of seismic activity from Mars and this is due to the season. During the winter in the Northern hemisphere, the tenuous winds of the Red Planet are still strong enough to mess the InSight seismometer, called the Seismic Experiment for Interior Structure (SEIS). During the last winter, it was not able to pick up any marsquake due to the wind. However, the summer period is when seismic data is pouring in.
“It’s wonderful to once again observe marsquakes after a long period of recording wind noise,” said John Clinton, a seismologist who leads InSight’s Marsquake Service at ETH Zurich. “One Martian year on, we are now much faster at characterizing seismic activity on the Red Planet.”
To improve detection, the mission team has used the lander’s robotic scoop to bury the cable that connects the seismometer to InSight. While it’s summer in the Northern Hemisphere of Mars, the planet is around its furthest point from the Sun, so it’s not getting much sunlight at the moment. The mission will undergo a technical shutdown until July when more sunlight will start pouring down on it.