NASA says Mars is ‘seismically active’
Earth has earthquakes, so naturally Mars has marsquakes.
In fact, our red neighbor planet has had hundreds of quakes over the past year. The marsquakes were recorded by NASA’s InSight Lander, a robot spacecraft that landed on Mars in November 2018.
“We’ve finally, for the first time, established that Mars is a seismically active planet,” NASA’s Bruce Banerdt said at a news conference with reporters last week. He said Mars is more seismically active than the moon but is less active than the Earth.
Researchers determined that Mars trembles more often – but also more mildly – than expected. Over the past year, more than 450 seismic signals have been recorded on the Martian surface, the vast majority of which are probably marsquakes (as opposed to “noise” created by environmental factors such as wind).
The quakes are mostly on the mild side; only a handful were magnitude 3 to 4.
The basic cause of Martian quakes is a long-term cooling of the planet, which makes it contract and fractures its brittle outer layers, Banerdt said. But it’s not clear what detailed mechanisms bring on specific quakes, he said.
InSight is the first mission dedicated to looking deep beneath the Martian surface, according to NASA. Among its science tools are a seismometer for detecting quakes, sensors for gauging wind and air pressure, a magnetometer and a heat flow probe designed to take the planet’s temperature.
As for the weather, the spacecraft’s meteorological sensors have detected thousands of passing whirlwinds, which are called dust devils when they pick up grit and become visible.
Overall, InSight’s observations will help scientists better understand how rocky planets such as Mars, Earth and Venus form and evolve, according to Space.com.
“Knowledge of the level of seismic activity is crucial for investigating the interior structure and understanding Mars’ thermal and chemical evolution,” Banerdt wrote in an overview article in the British journal Nature Geoscience that was published Monday.
That publication – along with the journal Nature Communications – features four papers from the InSight team, all of which were published Monday.