Researchers have found that NASA’s InSight rover recorded a Martian earthquake in the Amazonis Planitia region on December 24, 2021, which was the result of a falling meteorite – the first time the mission witnessed the formation of a crater on the planet. Scientists found this out by looking at pre- and post-fall photos from the Mars Reconnaissance Orbiter (MRO), which show a 150-meter gap in the landscape.
It is believed that the meteoroid was between 5 and 12 meters long. It would have burned up in Earth’s atmosphere, but was large enough to survive in the ultra-thin atmosphere of Mars. The impact was strong, digging a hole 21 meters deep and throwing debris 37 km from the crater. It also exposed subsurface ice previously unseen so close to the Martian equator. Sound adaptation of the Insight data shows how loud this event was compared to regular activity on Mars.
This event took some time to confirm. The Malin Space Science Systems team used two MRO cameras (a black-and-white Context Camera and a color Mars Imager) in February to detect the crater. Images from a color camera helped narrow down the time of the collision to a 24-hour window.
Separately, the team suggested that 20 of the roughly 1,300 Martian earthquakes detected by the InSight rover could be signs of magma. As Gizmodo explains, the spectral signature of earthquakes suggests a relatively soft crust in the region of the Cerberus pits on Mars. Combined with the dark dust, this suggests that volcanic activity may have occurred on the planet within the last 50,000 years.
The discovery could help the scientific community understand the geological chronology of Mars by determining the rate at which craters appear on the planet. It could also be crucial for colonists and explorers of Mars, who may need subsurface ice for life support and rocket fuel. People visiting Mars could take fewer supplies or extend their stay there.
This news also has a bitter aftertaste. NASA previously warned that InSight would not be able to operate much longer, and now expects the rover to shut down after six weeks as dust accumulation limits the efficiency of its solar panels. That’s better than the late-summer shutdown the agency predicted this spring, but the meteorite detection could be InSight’s last big achievement.