On March 7 and 18, 2021, NASA’s InSight lander detected 3.3- and 3.1-magnitude marsquakes originating in a location called Cerberus Fossae, further supporting the idea that this location is seismically active.
InSight is the first mission dedicated to looking deep beneath the Martian surface.
Among the lander’s science tools are a seismometer called the Seismic Experiment for Interior Structure (SEIS) for detecting quakes, sensors for gauging wind and air pressure, a magnetometer, and a heat flow probe designed to take the planet’s temperature.
The SEIS instrument has recorded over 500 quakes to date, but because of their clear signals, March 7 and 18 events are among the best quake records for probing the interior of the planet.
These two marsquakes add weight to the idea that Cerberus Fossae is a center of seismic activity.
“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,’” said Dr. Taichi Kawamura, a researcher at the Institut de Physique du Globe de Paris.
“Earthquake waves travel more directly through the planet, while those of moonquakes tend to be very scattered; marsquakes fall somewhere in between.”
“Interestingly, all four of these larger quakes, which come from Cerberus Fossae, are ‘Earth-like’.”
The new quakes have something else in common with InSight’s previous top seismic events, which occurred almost a full Martian year (two Earth years) ago.
They occurred in the Martian northern summer. Scientists had predicted this would again be an ideal time to listen for quakes because winds would become calmer.
During the past northern winter season, InSight couldn’t detect any quakes at all.
“It’s wonderful to once again observe marsquakes after a long period of recording wind noise,” said Dr. John Clinton, a seismologist at ETH Zurich.
“One Martian year on, we are now much faster at characterizing seismic activity on the Red Planet.”
This article is based on text provided by the National Aeronautics and Space Administration.