Mars: Researchers develop computational model for sound

When it comes to sound, a person on Mars would most likely feel at home on a mountain top. The sound there would be most comparable to that on Earth, say US and French researchers who have been working on a model of the speed of sound and sound attenuation on Mars. In other places, however, the sound could be very strange due to different sound velocities. For example, in the vicinity of the Mars robot Perseverance, high-pitched sounds would reach the ear faster than low-pitched sounds – a very difficult sound situation by human standards. The recently published study makes it possible to calculate the values at any location at any time on Earth's neighboring planet.

The researchers found that the strong temperature fluctuations on Mars in particular have a significant influence on sound propagation. Due to their significantly higher levels, the variations are far greater than those on Earth. Depending on the time of year, temperatures can drop to –125°C or rise to 30°C during the day. The carbon dioxide content in the atmosphere is also decisive, but not to the same extent as the temperature. The concentration of dust, on the other hand, does not play such a major role. The calculations were based on measurements from various locations on the surface of Mars, which were collected by probes and robots.

Why sound research is important

Sound research plays a major role regarding future Mars missions, especially if there should one day be a manned mission. Acoustics have proven to be a reliable method for investigating atmospheric properties, for example during missions to Venus or the moon Titan. On Mars, the NASA Perseverance rover and the Chinese Zhurong rover recorded sounds with their microphones. Especially those from artificial sound sources, such as the Ingenuity helicopter, proved to be helpful in creating the sound model.

The sound model will enable researchers to better interpret recorded sounds from the red planet in the future. For example, information about the weather and climate conditions on Mars could be obtained. The findings would also be useful for communication and navigation.

(mki)