(ORDO NEWS) — A seismometer mounted on NASA’s InSight lander has recorded two of the largest seismic events ever detected on the surface of Mars – a quake of magnitude 4.2 and a magnitude 4.1.
These two quakes are the first recorded events of their kind to occur on the side of the planet opposite InSight’s location, and each of these events is about three times as intense as the previous largest quake on record.
Seismic wave data from these events could help researchers better understand the interior of Mars, in particular the boundary between the core and the mantle, the researchers report.
Anna Horleston of the University of Bristol, England, and her colleagues were able to identify PP and SS waves from a magnitude 4.2 event called S0976a and locate its origin in the Mariner Valleys, a vast network of canyons.
The S1000a event, which has a magnitude of 4.1 and was recorded 24 days later, was recorded using PP and SS waves, as well as Pdiff.
This was the first time that Pdiff-class waves were detected by the InSight mission. The researchers were unable to definitively pinpoint the location of the source S1000a, but found that, like the source S0976a, it is located on the far side of Mars.
If these two quakes were observed using P and S waves, then the shadow of the planet’s core would interfere with observations, but the PP and SS waves do not move in a straight path, but are reflected from the surface before reaching the seismometer.
Regarding the depth of these quakes, the scientists were able to find that the S0976a event is much deeper than the S1000a event. Compared to the rest of the seismic events recorded so far with the help of the InSight spacecraft, these two new marsquakes demonstrate extremely unusual properties, the authors note.
Contact us: [email protected]