Nasa has been able to confirm that Mars is seismically active after its Insight spacecraft was able to detect two quakes large enough to be tracked back to their source.
First landing in November 2018 in the Elysium Planitia region, Insight (pictured above) detected over 100 “Marsquakes” in its first year on the planet. However, there was some debate amongst scientists as to whether the vibrations detected were legitimate seismic activity or just Martian wind rattling its instruments.
Dr Bruce Barnerdt, InSight principal investigator and lead author on one of the studies, said: “We finally have, for the first time, established that Mars is a seismically active planet.”
The first so-called “Marsquake” was recorded by InSight’s onboard sensors in April 2019. Since then, it has detected more than 450 quivers, much smaller than anything that would be felt on Earth.
Two of the quakes were found to emanate from a geologically active area known as Cerberus Fossae, around 1,000 miles east of Elysium Planitia.
The finding is significant as the quakes are thought to be created by the cooling and subsequent shrinking of the planet, alongside general tectonic plate shifting like we have on Earth.
The Martian seismic activity recorded by the lander’s seismometer – a ground-motion detection sensor – was found to be greater than that of the Moon, but less than that of Earth.
“As the planet cools, it contracts and then the brittle outer layers have to fracture in order to sort of maintain themselves on the surface. That’s kind of the long-term source of stresses,” said planetary geophysicist and mission principal investigator Bruce Banerdt.
The team believes that understanding more about the seismic activity of planets other than Earth could reveal clues about how the Solar System formed.
Dr Domenico Giardini, of ETH Zurich in Switzerland and lead author on one of the studies, added: “Marsquakes have characteristics already observed on the Moon during the Apollo era, with a long signal duration (10 to 20 minutes) due to the scattering properties of the Martian crust.”
The researchers devised a magnitude scale tailored to Mars, but similar to the one used for earthquakes. The strongest of the quakes were a little less than magnitude 4, meaning they would be felt on the surface perhaps dozens of miles from the epicenter but probably would not do much damage.
Evidence of dust devils, which are whirls of Martian soil whipped up by the wind that spin like a tornado at nearly 60mph, were observed a month after InSight touched down on Mars.
The £633 million Nasa mission is expected to continue for another year.
In June, Nasa’s Curiosity rover discovered the largest amount of methane measured during its near seven-year mission, a potential sign of life after recent doubts about how much methane the planet really produces.
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