On September 18, NASA InSight lander’s seismometer detected one of the biggest and longest-lasting marsquakes — quakes on mars — with a magnitude of 4.2. The tremors lasted for about an hour and a half. Scientists are still trying to determine the origin of the marsquake but it is too far from almost all of the previously recorded large marsquakes.
The tremors were third in a month that saw two more marsquakes on August 25 — one of a magnitude 4.2 and another of a 4.1 magnitude. According to NASA, the magnitude 4.2 event on August 25 had originated some 8,500 kilometres far from the InSight lander — the farthest quake detected by the lander so far. Compared to that, the 4.1 magnitude quake was much closer — 925 kilometres away.
Scientists are still working out the exact location and direction of waves of the September 18 event. They are guessing that the origin of the marsquake could either lie in 1,609 km away Cerberus Fossae — a region that was probably filled with lava millions of years ago — or Valles Marineris — grand canyon system along the Martian equator, which is 9,700 km far.
According to scientists, the two events detected were very different from each other. The 4.2 magnitude event was dominantly slow and had low-frequency vibrations. The 4.1 magnitude event, on the other hand, was dominated by fast and high-frequency vibrations.
NASA scientists believe that the detections are important to understand Mars’ interior because scientists could observe how seismic waves change when and figure the interior structure — a technique used in understanding Earth’s interior as well. Highlighting the importance of the detections, InSight’s principal investigator Bruce Banerdt says in a statement, “Even after more than two years, Mars seems to have given us something new with these two quakes, which have unique characteristics.”
Meanwhile, on September 18, InSight lander finished its 1000 sols (Martian day) on mars. When the detection was official, another tweet from the mission’s handle on September 22read, “A great way to celebrate my 1,000th sol/day on Mars.” The lander was launched from Earth in May 2018 and landed on Mars in November 2018.
I caught one of the biggest and most distant #marsquakes yet—about magnitude 4.2—this past Saturday. A great way to celebrate my 1,000th sol/day on Mars. All thanks to my team for working to keep my solar panels clear enough so I could keep going.More: https://t.co/WUd0QAHhys
— NASA InSight (@NASAInSight) September 22, 2021
The official Twitter handle of the InSight mission tweeted a picture of the lander partially covered in dust.