Surprising discovery: Martian quake's origin revealed as tectonic activity

In a startling revelation, the source of a massive earthquake on Mars has been identified, and it's not what scientists initially expected. The earthquake, which was detected on May 4, 2022, by NASA's InSight lander and registered at a magnitude of 4.7, has been attributed to colossal tectonic activity within the Martian crust. This discovery comes as a result of the efforts of an international team led by planetary physicist Benjamin Fernando from the University of Oxford in the United Kingdom.

What makes this finding truly unexpected is that Mars lacks tectonic plates, which are typically associated with such seismic events. The prevailing hypothesis had been that a giant meteorite impact might have triggered the quake, but this avenue led to a dead end.

"We still believe that Mars lacks active plate tectonics today, so this earthquake was likely caused by the release of stress within Mars' crust," explained Fernando. "These stresses are the outcome of billions of years of evolution, including the cooling and shrinking of different parts of the planet at varying rates."

InSight, NASA's spacecraft, spent four years on Mars closely monitoring the planet's interior before it ceased operations at the end of 2022. During its mission, InSight recorded hundreds of quakes and tremors. Some of these seismic events were indeed linked to space rocks impacting the Martian surface, while others were associated with magmatic activity, indicating that the red planet is not as geologically inactive as previously believed.

Fernando and his team set out to unravel the mystery behind the largest quake ever recorded by InSight, known as S1222a. The seismic data closely resembled patterns from previously identified impact events. In response, researchers embarked on a significant international effort, enlisting support from global space agencies with satellites orbiting Mars.

Despite the fact that other quakes could be traced to fresh and easily identifiable impact craters and blast zones, S1222a didn't leave behind any such telltale signs. This led the researchers to conclude that the most plausible explanation was tectonic movement, challenging prior assumptions about Mars's geological activity.

Regrettably, InSight is no longer operational for further investigation. Nonetheless, the wealth of data it collected will provide scientists with valuable material to analyze for years to come. Future Mars missions and research endeavors may help address some of the questions raised by this groundbreaking discovery.

"We still do not fully comprehend why certain areas of the planet exhibit higher stress levels than others, but findings like these pave the way for further exploration," Fernando remarked. "Someday, this information may guide us in determining safe locations for human habitation on Mars and where to exercise caution."