First sound recordings of Mars by the InSight probe
The short-period (SP) sensors on the SEIS seismometer and the ultrasensitive pressure sensor on InSight's APSS weather station have probably just returned the first sounds ever recorded on the Red Planet.
Publication date: 01/12/2018
General public, Observatories, Press, Research
Related observatories : InSight Observatory
Related themes : Earth and Planetary Interiors
The first sound recordings were presented by Professor Tom Pike (Imperial College London) to the science team present at the Jet Propulsion Laboratory on Saturday 1 December 2018. The data was acquired during the first health check of the SEIS seismometer following InSight’s landing on 26 November.
After being switched on, the SP sensors captured the sound that the wind makes as it vibrates InSight’s flexible solar panels as it circulates around the lander. It’s as if the probe has become a giant microphone: the solar panels act a bit like the eardrum of an ear, with the waves being transmitted through the structure of the lander to the SP sensors. The SP sensors are sensitive to frequencies of up to 50 Hz, the lowest limit of what the human ear is capable of hearing (although they could record sounds of up to 90 Hz).
The area where the InSight lander landed is apparently very windy, hence the throbbing low-frequency rumble from the effect of the air masses on the probe. The direction of the winds (north-west to south-east) measured by the SP sensors seems to correspond to the tracks that dust devils leave on the surface of Mars and is also consistent with atmospheric circulation models.
The ultrasensitive pressure sensor of the APSS weather station (under the responsibility of Don Banfield, Cornell University) produced other sound data, different from that of the SEIS seismometer. Operating at lower frequencies than the SP sensors, the weather station directly recorded the movement of air masses. To be audible to the human ear, the APSS data (acquired at 10 Hz) was processed and shifted to higher frequencies by Nicolas Verdier (CNES).
Once it has been placed on the surface of Mars and covered by its thermal and wind protection shield (WTS), the SEIS seismometer will no longer be able to provide sound data, since wind is a source of noise that seismologists dread. Wind activity can interfere critically with the seismometer’s primary mission, which is to record the smallest displacements of the ground caused by seismic tremors in order to determine the internal structure of Mars.
However, the recordings from the APSS meteorological station will enable us to continue listening to the activity of the atmosphere around the lander, day and night, whatever the season. In addition to its scientific value, this sound database will be used to further enhance immersion in virtual reality applications, such as the VR2Mars programme developed by VR2Planets in conjunction with IPGP, IRAP and CNES.
Find out more:
- Discover the sounds recorded by InSight in this summary video from NASA
