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 reported on Tuesday.
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.