NASA’s robotic probe InSight has detected and measured what scientists believe to be a “marsquake,” marking the first time a likely seismological tremor has been recorded on another planet, the Jet Propulsion Laboratory in California said on Tuesday, ONA reports citing Reuters.
The breakthrough came nearly five months after InSight, the first spacecraft designed specifically to study the deep interior of a distant world, touched down on the surface of Mars to begin its two-year seismological mission on the red planet.
The faint rumble characterized by JPL scientists as a likely marsquake, roughly equal to a 2.5 magnitude earthquake, was recorded on April 6 - the lander’s 128th Martian day, or sol.
It was detected by InSight’s French-built seismometer, an instrument sensitive enough to measure a seismic wave just one-half the radius of a hydrogen atom.
“We’ve been collecting background noise up until now, but this first event officially kicks off a new field: Martian seismology,” InSight principal investigator Bruce Banerdt said in a news release.
Scientists are still examining the data to conclusively determine the precise cause of the signal, but the trembling appeared to have originated from inside the planet, as opposed to being caused by forces above the surface, such as wind.
The size and duration of the marsquake also fit the profile of some of the thousands of moonquakes detected on the lunar surface between 1969 and 1977 by seismometers installed there by NASA’s Apollo missions, said Lori Glaze, planetary science division director at NASA headquarters in Washington.
The lunar and Martian surfaces are extremely quiet compared with Earth, which experiences constant low-level seismic noise from oceans and weather as well as quakes that occur along subterranean fault lines created by shifting tectonic plates in the planet’s crust.
Three other apparent seismic signals were picked up by InSight on March 14, April 10 and April 11 but were even smaller and more ambiguous in origin, leaving scientists less certain they were actual marsquakes.