NASA's Perseverance rover captured the humming sounds of the tiny Ingenuity helicopter flying above the Martian surface.
Why it matters: By recording sound on Mars, scientists will be able to learn more about how the Martian atmosphere works and potentially diagnose problems with Perseverance, should they pop up.
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Driving the news: NASA released a video Friday showing Ingenuity's fourth flight on April 30 when the helicopter flew a 872-foot round-trip test.
Perseverance recorded the flight, capturing the Martian wind and hum of the helicopter's blades spinning at 2,537 rpm. (If you're watching the full video, it helps to use headphones.)
"We had carried out tests and simulations that told us the microphone would barely pick up the sounds of the helicopter, as the Mars atmosphere damps the sound propagation strongly," David Mimoun, the science lead for Perseverance's SuperCam Mars microphone, said in a statement. "We have been lucky to register the helicopter at such a distance."
The big picture: Ingenuity is the first human-made drone to ever fly on another planet, and NASA hopes the tests it's running with the 4-pound helicopter will pave the way for future missions using other drones on Mars and elsewhere.
What's next: NASA will continue to test Ingenuity on Mars, allowing it to go on farther flights and one-way trips, potentially to help scout out areas of interest for Perseverance.
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