If you hear one new thing today, how about making it the sound of wind on Mars?
Two microphones aboard the Perseverance Rover have "recorded nearly five hours of Martian wind gusts, rover wheels crunching over gravel and motors whirring as the spacecraft moves its arm," NASA says.
NASA has launched an interactive resource that allows listeners to hear recordings taken millions of miles away on the surface of the Red Planet.
🔊 Sound check: hear some recordings from the two microphones aboard @NASAPersevere, and learn how scientists use them https://t.co/rjiX1rkke0@NASAInSight has also used its seismometer to "hear" sounds on Mars: https://t.co/OCttAJ3x10 pic.twitter.com/XChU97TdhB
— NASA Mars (@NASAMars) October 18, 2021
It sounds even better if you listen through headphones
Although it's subtle, you don't have to be a planetary scientist to hear the difference between sounds on Earth and sounds on Mars.
NASA describes the astro-acoustics of Mars this way: "If you were standing on Mars, you'd hear a quieter, more muffled version of what you'd hear on Earth, and you'd wait slightly longer to hear it."
Baptiste Chide is a planetary scientist who is studying the audio's data at L'Institut de Recherche en Astrophysique et Planétologie in France. "Martian sounds have strong bass vibrations, so when you put on headphones, you can really feel it. I think microphones will be an important asset to future Mars and solar system science," Chide says.
David Gruel, one of the experts who study the rover's audio, says wind on Mars sounds different because of Mars' unique atmosphere. He spoke with Weekend Edition's Lulu Garcia-Navarro in March.
"So the wind speed in a carbon dioxide environment is slower than it is in our air environment. And so you might not hear as much screeching as you would hear in Earth atmosphere, but you'd hear more of the lower-end noises in the Mars atmosphere than you would do here on Earth," Gruel reports.
Because Mars' atmosphere is much less dense than Earth's, higher-pitch sounds like whistles and some bird calls would be almost imperceptible on Mars.
Why Martians sounds are important
NASA's resource also lets listeners compare common Earth sounds, such as ocean waves crashing on a shore, with what they might sound like if recorded on Mars.
![NASA's Mars Perseverance rover took this image of Mars' surface on Sep. 25, 2021.](https://npr.brightspotcdn.com/dims4/default/50ab4ff/2147483647/strip/true/crop/1088x816+0+0/resize/880x660!/quality/90/?url=https%3A%2F%2Fmedia.npr.org%2Fassets%2Fimg%2F2021%2F10%2F22%2Fmars_perseverance_nrf_0213_0685859984_571eby_n0072050ncam05213_06_0llj-07a77662e568e0051060ebda30b2bce777b08f05.png)
The scientists took into account atmospheric pressure, density and chemistry to simulate how the Earth's sound might change on Mars.
According to NASA, understanding the nature of sound on Mars could one day help scientists diagnose problems with a spacecraft on a distant planet, just like a car mechanic might listen closely to an engine to know what's wrong with it.
Further discoveries
NASA's Perseverance Rover has been busy since landing on the surface of the Red Planet in February. In only 237 sols (or Martian days), Perseverance has provided scientists with over 150,000 images, helped launch the first test of powered flight on another planet and has even created oxygen from the Martian atmosphere.
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