For the first time, NASA has captured the weird sound of a meteoroid sailing through another planet’s atmosphere and crashing to the ground.
The recording, posted Sept. 19 on YouTube, combines “seismic and acoustic waves” detected when a space rock hit Mars on Sept. 5, 2021, the NASA Jet Propulsion Laboratory says in a news release.
Lasting only about 3 seconds, the sound begins with a hiss — the rock flying through the sky — and ends with “bloops.”
“It was the first time the sound of a meteoroid impact was captured occurring on another planet, and it might not be what you expect,” the lab reports.
“You hear three ‘bloops’ representing distinct moments of the impact: the meteoroid entering Mars’ atmosphere, exploding into pieces, and striking the ground. The peculiar sound is caused by an atmospheric effect that’s also been observed in deserts on Earth, where lower-pitched sounds arrive before high-pitched sounds.”
The meteoroid — “the term for incoming space rocks before they hit the ground” — exploded into at least three pieces, leaving three distinct craters, scientists say.
NASA says its InSight lander picked up the seismic waves and NASA’s Mars Reconnaissance Orbiter flew over the impact site and photographed “three darkened spots on the surface.”
A paper published Sept. 19 in the peer-reviewed journal Nature Geoscience reports NASA has recorded four meteoroid impacts on Mars since August 2021, “between 53 and 180 miles (85 and 290 kilometers) from InSight’s location.”
All four produced marsquakes (like earthquakes) in the 2.0 magnitude range, officials say.
“Researchers have puzzled over why they haven’t detected more meteoroid impacts on Mars,” NASA says.
“The Red Planet is next to the solar system’s main asteroid belt, which provides an ample supply of space rocks to scar the planet’s surface. Because Mars’ atmosphere is just 1% as thick as Earth’s, more meteoroids pass through it without disintegrating,” NASA says.
It’s possible more impacts have occurred since InSight landed in 2018, but they were “obscured by noise from wind or by seasonal changes in the atmosphere,” the InSight team says.
The paper’s lead author, Raphael Garcia of France’s Institut Supérieur de l’Aéronautique et de l’Espace in Toulouse, says such impact sites “are the clocks of the solar system.”
“Scientists can approximate the age of a planet’s surface by counting its impact craters: the more they see, the older the surface,” he says in the news release.
This story was originally published September 19, 2022 3:57 PM.