Skip to main content

What Perseverance rover recordings tell us about sound on Mars

The Perseverance rover captured the world’s imagination when it recorded sounds from the surface of Mars shortly after its arrival on the red planet in 2021. It recorded sounds of the Martian wind, as well as the noises it made itself, and it even managed to capture the sounds of the Ingenuity helicopter in action. Now, scientists have analyzed these recordings to learn about how sound propagates on Mars, and found that the speed of sound isn’t constant there — it depends on the sound’s pitch.

NASA’s Perseverance Rover Captures Puff, Whir, Zap Sounds from Mars

One of the challenges of recording sounds on Mars is that because the atmosphere is so thin there, scientists were unsure if it was going to be possible to record sounds at all. The atmosphere is made up mostly of carbon dioxide, which tends to absorb sound waves as well. So the fact that the microphones on Perseverance were able to record Ingenuity from a distance of 80 meters was a surprise and a delight.

But this means that the recordings which are available tend to be quiet. “Mars is very quiet because of low atmospheric pressure,” said coauthor of the study Baptiste Chide of Los Alamos National Laboratory in New Mexico in a statement. “But the pressure changes with the seasons on Mars.” That means we can expect changes to the sounds recorded in future. “We are entering a high-pressure season,” Chide said. “Maybe the acoustic environment on Mars will be less quiet than it was when we landed.”

The strangest finding from the study is that the speed of sound on Mars is variable. Here on Earth, the speed of sound is 767 mph. But on Mars, the speed sound travels at depends on its pitch: Low-pitched sounds travel at about 537 mph, and higher-pitched sounds move considerably faster at 559 mph. This seems to be due to the extreme nature of the thin, cold atmosphere.

The recordings were made using Perseverance’s two microphones: One on its SuperCam instrument, used to hear the sounds made when a laser strikes its rock target to perform spectroscopy, and a second which records the sounds of puffs of air from the Gaseous Dust Removal Tool which clears rock surfaces of debris. The SuperCam microphone is the main one being used for the science work.

NASA/JPL-Caltech

“The microphone is now used several times a day and performs extremely well; its overall performance is better than what we had modeled and even tested in a Mars-like environment on Earth,” said David Mimoun, professor at Institut Supérieur de l’Aéronautique et de l’Espace (ISAE-SUPAERO) and lead of the team that developed the microphone experiment. “We could even record the humming of the Mars helicopter at long distance.”

The viability of researching sounds on Mars opens new avenues of research. “It’s a new sense of investigation we’ve never used before on Mars,” said Sylvestre Maurice, an astrophysicist at the University of Toulouse in France and lead author of the study. “I expect many discoveries to come, using the atmosphere as a source of sound and the medium of propagation.”

Editors' Recommendations

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
NASA’s damaged Ingenuity helicopter spotted in Mars rover photo
A Mars landscape with NASA's Ingenuity helicopter in the background.

A Mars landscape with NASA's Ingenuity helicopter seen on the dune in the distance. NASA/JPL-Caltech/ASU

NASA’s Mars rover, Perseverance, has captured an image (above) showing the final resting place of the damaged Mars helicopter, Ingenuity.

Read more
Yes, Perseverance is exploring an ancient lake bed but no, it hasn’t found signs of life (yet)
The Jezero Crater on Mars, showing a delta where an ancient lake was once located.

A new study shows exciting results about the Jezero Crater on Mars, where the Perseverance rover is currently exploring -- but despite what some headlines suggest, Perseverance hasn't yet found evidence of life on the red planet.

The Jezero Crater is the most exciting place on Mars and was deliberately chosen for the Perseverance rover to explore because it's the best guess scientists have at a location that could potentially have hosted microbial life billions of years ago. What makes the crater so special is the large delta that exists there, which is thought to have been an ancient wetland. An ancient lake is believed to have existed in the crater long ago -- which would make it a hospitable place for life to have emerged. The new research confirms that this area did indeed host a lake, but it doesn't say anything about whether there was life there.

Read more
NASA says goodbye to Mars helicopter Ingenuity after an incredible 72 flights
NASA’s Ingenuity helicopter unlocked its rotor blades, allowing them to spin freely, on April 7, 2021, the 47th Martian day, or sol, of the mission.

It's a sad day for space fans, as the plucky little helicopter Ingenuity has finally come to the end of its mission on Mars. The helicopter will not be making anymore flights due to damage to one of its rotors that occurred during a recent landing, NASA said in an announcement on Thursday, January 25.

The mission was originally planned to make just five flights and to last 30 days, but has been successful beyond what anyone had imagined. The helicopter has made a total of 72 flights over the course of its three-year mission, which began when it was set down on the surface of Mars by the Perseverance rover. The rover arrived on Mars with the helicopter tucked up underneath its belly in February 2021, and Ingenuity sat on the surface for the first time in April 2021. It then made history by becoming the first rotorcraft to fly on another planet with its maiden flight.

Read more