NASA scientists have reduced a year of audio recordings of Perseverance on the Martian surface to a five-hour playlist of red planet’s best hits (you can listen to some here). The sounds are strangely quiet and offer a new way to explore the Martian environment. They have already helped confirm some theories about how sounds travel around the planet.
The rover’s audio was first released last year: none of the sounds were very pleasing to the ear, possibly due to electromagnetic interference. The last sounds are softer than those screams; An analysis of sounds and what they can tell us about how sound travels to Mars was published in Nature last month.
Baptiste Chide, a planetary scientist at Los Alamos National Laboratory, told Gizmodo in a video call last year that the audio heard on Mars would sound like it was crossing a wall, because the Martian atmosphere was 1% so dense as that of the Earth. But Chide was still amazed at how calm Mars turned out to be. “It’s so quiet that at one point we thought the microphone was broken,” Chide said in a statement from the Acoustical Society of America.
The Perseverance rover landed on Mars in February 2021 with a set of technologies designed to find out if Mars ever hosted microbial life in its ancient past. But in addition to these scientific instruments, the rover also included two microphones, made with commercial components, to record the first audio data on Mars.
One of Perseverance’s microphones is connected to the rover’s frame and is located just above one of its wheels. This microphone is surrounded by a mesh to protect it from Martian dust, which is propelled by the planet’s winds and can be fatal to spacecraft, as the Opportunity rover learned so inopportunely. The other microphone is attached to the rover’s SuperCam, one of the machine’s main cameras located on one arm above the rover’s frame.
As a result, the researchers found that the last microphone picked up the sounds of the wind blowing around the rover, while the previous microphone picked up more sounds from the rover’s activities. The microphones successfully caught the groan of the Ingenuity helicopter in flight, even when the helicopter was more than 91.44 m away.
In March, Chide’s team used the SuperCam microphone to measure the speed of sound on Mars. The latest research took advantage of the two microphones to characterize Mars’ acoustic environment and used near and far sound sources to show how the heavy carbon dioxide atmosphere affected the sound’s ability to travel.
Mars is much colder than Earth, with a finer atmosphere. NASA scientists expected the sound to travel more slowly to Mars as a result, and it did. The researchers found that higher-frequency sounds traveled faster than lower-frequency noise.
The sound on Mars will change over the course of 687 days on the planet. During the Martian winter, carbon dioxide in the polar regions of the planet freezes, which will cause the intensity of the sounds to fluctuate, according to the statement. So stay tuned. As long as Perseverance works as its name suggests, we should soon get a more diverse portfolio of Martian blends.
More information: 16 minutes from Perseverance Rover Going Kssst, Tiktik and Pffft