Science Gazette

Perseverance captures the first sounds from Mars


NASA’s Perseverance rover, which has been exploring Mars’ surface since February 2021, has captured the Red Planet’s auditory environment for the first time. An international team1 lead by Paul Sabatier, a professor at the University of Toulouse III, and involving scientists from the CNRS and ISAE-SUPAERO analyzed the noises, which were collected using the SuperCam equipment created in France under the authority of the French space agency CNES. Their results will be published in Nature on April 1, 2022.

For the last 50 years, interplanetary missions have returned hundreds of stunning photographs of Mars’ surface, but not a single sound. NASA’s Perseverance mission has finally broken the stillness by capturing the first ever Martian noises. The research team1 behind the French-US SuperCam2 sensor deployed on Perseverance was persuaded that studying Mars’s soundscape may help us better comprehend the planet. This scientific problem inspired them to create a microphone for Mars exploration at ISAE-SUPAERO in Toulouse, France.

Perseverance began recording sounds from Mars on February 19, 2021, the day after its arrival. These noises are perceptible to humans at frequencies ranging from 20 Hz to 20 kHz. First and foremost, they demonstrate that Mars is very silent, so quiet that the scientists mistook the microphone for broken on multiple occasions. Aside from the wind, it is evident that natural sound sources are few.

In addition to this examination, the scientists concentrated on the noises produced by the rover itself3, such as shock waves created by the SuperCam laser’s impact on rocks and flights by the Ingenuity helicopter. They were able to precisely characterize the acoustic features of the Martian atmosphere by investigating the transmission of these sounds on Mars, whose behavior is well known on Earth.

See also  Breakthrough in Cosmic Physics: Scientists Create Particle-Antiparticle Pairs in a Vacuum

The researchers discovered that the speed of sound on Mars is lower than on Earth: 240 m/s against 340 m/s on our planet. The most shocking discovery is that there are two speeds of sound on Mars, one for high-pitched noises and one for low frequencies4. Sound attenuation on Mars is stronger than on Earth, particularly for high frequencies, which, unlike low frequencies, attenuate quite fast even over short distances. All of these variables would make it impossible for two persons standing merely five meters apart to converse. They are caused by the Martian atmosphere’s composition (96 percent CO2, compared to 0.04 percent on Earth) and the very low atmospheric surface pressure (170 times lower than on Earth).

After one year of operation, a total of five hours of auditory environment recordings have been acquired. In-depth investigation of these noises has revealed the sound produced by the turbulence of the Martian atmosphere. The study of this turbulence at scales 1000 times smaller than previously known might improve our understanding of the interaction of Mars’ atmosphere with its surface. Other robots outfitted with microphones may be used in the future to help us better comprehend planetary atmospheres.

Related Posts

Leave a comment

You must be logged in to post a comment.