'Subwoofers won't work on Mars':  NASA's rover discovers inconsistency in the speed of sound on Red Planet

Produced by: Tarun Mishra Designed by: Manoj Kumar

Unique Sound Behaviour on Mars

Researchers have discovered that sound on Mars behaves very differently compared to Earth, with distinct variations based on time and location.

Credit: ASA/JPL-Caltech

Perseverance Rover's Contributions

NASA's Perseverance rover, equipped with several microphones, has recorded various sounds on Mars, including the spluttering of dust devils, revealing unusual acoustic properties.

Impact of Atmospheric Composition

Sounds below 240 hertz travel slower on Mars due to its atmosphere, which is 95% carbon dioxide. This element absorbs some sound energy, affecting lower frequencies.

Study of Sound Propagation

Scientists from French and U.S. institutions examined how sound speed and attenuation vary within the first 60 feet of Mars' atmosphere, considering factors like atmospheric pressure, temperature, and chemical composition.

Variations Across Mars

Using data from the Mars Climate Database, the team calculated sound speed and attenuation across different times of the year and various Martian landscapes, noting significant changes due to temperature and carbon dioxide fluctuations.

Temperature Fluctuations

In polar regions, midday temperatures can change by 108 degrees Fahrenheit (60 degrees Celsius), and carbon dioxide levels can vary by 30%, impacting sound propagation significantly.

Findings Published

The study's results, published in JGR: Planets, show that unlike Earth, sound speed and attenuation on Mars are greatly influenced by carbon dioxide levels and temperature fluctuations.

Practical Implications

These findings suggest that sound speed can change by up to 100 feet per second during the day, with higher temperatures causing sounds to die down faster. This variability could affect future Mars missions, particularly crewed ones.

Modelling Sound Propagation

The researchers' model can predict sound speed and attenuation for any location on Mars at any time, aiding in understanding sound-producing objects on the planet and offering insights for future human residents on Mars.