- NASA shared the sound of a meteor falling to Mars, with photos of the impact craters, on Monday.
- The dwindling InSight lander has captured the acoustic and seismic noise of four meteor impacts.
Nobody had ever heard the sound of a meteor crashing into another planet until NASA's InSight lander recorded the seismic waves of a space rock striking Mars.
On September 5, 2021, a rock hurtling through space crossed the red planet's path. The meteor screamed towards the planet's dusty orange surface, sending a shock wave through the atmosphere.
Though it may have burned up from the friction and heat of plowing through Earth's atmosphere, the meteor survived the thin Martian air. It splintered into at least three pieces, which crashed into the planet's surface and made craters.
The InSight lander's seismometer, designed to measure Mars quakes and dust devils, was sensitive enough to detect the acoustic impact of the shock wave hitting the ground as well as the seismic waves from the meteor's crash landing. NASA shared audio of the whole event on Monday. Take a listen below.
"Strangely, it's more like a 'bloop' than a 'bam!'" science writer Corey Powell said on Twitter.
NASA's Mars Reconnaissance Orbiter, a satellite orbiting the planet, later captured images of the impact craters from the meteor.
"After three years of InSight waiting to detect an impact, those craters looked beautiful," Ingrid Daubar, a specialist in Mars impacts at Brown University, said in a NASA press release.
Since then, scientists have combed through previous InSight data and confirmed three other meteor impacts that occurred throughout 2020 and 2021, ranging from 53 to 180 miles away from the lander. The Mars Reconnaissance Orbiter later imaged the impact craters from those meteors, too.
The details of the four Mars meteor strikes were published in a paper in Nature Geosciences on Monday.
Because the impacts were so faint that scientists initially overlooked them, the study authors suspect that there could be other meteor impacts hiding in the last four years of seismometer data, lost in the seismic noise of a gust of wind, according to the press release.
InSight is nearing the end of its life
These are the first meteor impacts InSight has detected since it landed on Mars in 2018. The lander's powerful seismometer has detected over 1,300 Mars quakes, revealing that the planet has a molten core and a thin, fragmented crust like the moon's. InSight has also picked up the seismic rumbles of dust devils and gathered weather data.
The robot is running out of time, though. Its landing spot on the vast field of Elysium Planitia turned out to be surprisingly not windy. NASA usually relies on gusts of wind to blow the pervasive Martian dust off of its robot's solar panels. InSight has seen very few such cleaning events.
The buildup of dust has been slowly decreasing the lander's ability to generate power. In 2018, its battery charge was enough to run an electric oven for an hour and 40 minutes. These days, it could only run such an oven for 10 minutes, mission manager Kathya Zamora Garcia said in a May press conference.
As of Monday, according to the press release, NASA engineers believe the lander could run out of power and shut down completely sometime between October 2022 and January 2023.