Microphones on Perserverance

"Alien" sounds were recorded on Mars with microphones in the Perseverance vehicle on the surface of Mars. The sounds of a man-made spacecraft on the surface of the Red Planet consist of the sounds made by the wheels, the rotation of the engines and the laser device. Naturally, the voices of the helicopter named Ingenuity, on which Perseverance had brought the microphones, were naturally captured. The duration of the recorded audio consists of five hours. This sound also includes the sound of the Martian winds in the background. Greg Delory, one of the scientists, states that "We are very excited about the sounds recorded by instruments on the surface of Mars for a long time." Thus, for the first time, they listened to the Voices of Mars, so far away from our planet.
NASA has created an interactive website that gives listeners the chance to listen to recordings millions of kilometers from the Red Planet.

You can listen to how sounds from Earth would sound on Mars, and you can even record your own greeting and hear how you would sound on Mars.

NASA also recommends using headphones when listening to recordings, as the sounds from Mars are thinner and quieter than those on Earth, due to Mars' less dense atmosphere.

“If you blow on the top of a Coke bottle, the tone you get depends on the characteristics of the atmosphere and the size of the bottle,” Delory explained.
“If you do this on Mars, the coke bottle will emit a frequency that is about 2/3 the value you would get on Earth. There's a general shift in anything that sounds lower frequency."

Quiet or higher-pitched sounds, such as a person's whistling or bird chirping, are nearly imperceptible on Mars.

Engineers picked up the humming rotors of the microphone Ingenuity helicopter during its fourth flight, 30 meters, on April 80.

As CEO and co-founder of Heliospace, a NASA subsidiary company, Delory helped design the Mars microphone.

This microphone was part of the ill-fated Mars Polar Lander mission launched in 1999 but crashed onto the surface of Mars.
The authors of the study are excited to finally hear the voices they hoped to hear decades ago. Most of the microphone data are stated to be as expected.

The sounds produced by the off-road vehicle were always expected to be heard, and they say that this expectation has come true.

But it was never thought that the sound of a helicopter could be heard. Engineers at JPL say understanding the nature of sound on Mars may one day help them diagnose problems with a spacecraft on a distant planet. They liken it to a car mechanic listening closely to an engine and understanding what the problem is.

The two microphones in Perseverance are built from commercially available off-the-shelf devices. One of the microphones sits on the side of the rover's case. The second microphone is on Perseverance's mast as a complement to the SuperCam laser instrument's investigations of rocks and atmosphere.
The old microphone also helped design the Mars lander, which used similar off-the-shelf parts. Delory and her team tested their microphone concept using wind tunnels, vacuum chambers, and thermal chambers. They created test environments by creating Mars-like conditions.
Information from years ago has been reused in the current real environment. Repeated testing, including microphones, in desert environments yielded results. “It's great to finally have a microphone on Mars and have such a dedicated team behind it,” explains team leader Delory.