First magnitude 5 earthquake “heard” on Mars
A "Marsquake" with an estimated magnitude of 5 shook the Red Planet on the night of 04/05/2022. The French SEIS instrument, deployed on the ground by NASA's InSight lander, had a front-row seat. Our teams have transcribed the event in audio.
Publication date: 22/05/2022
General public, Observatories, Press, Research
Related observatories : InSight Observatory
Related themes : Earth and Planetary Interiors
The scientists and engineers in charge of the mission have been waiting for it since the start of operations at the end of 2018: an earthquake much larger than anything recorded to date, and in line with the mission’s most optimistic objectives, has just sounded on the Martian soil, Thursday May 05, 2022 in the middle of the night (1:27 a.m. French time, around 4 a.m. on Mars). With a magnitude of 5 on the Richter scale, it was a mission record, compared with 4.2 for the previous tremor in August 2021.
A video was produced thanks to the data deglitching efforts of Grégory Sainton, research engineer at IPGP, and the sonification work of Rémi Lapeyre, head of Insight/SEIS operations at CNES. (© CNES/NASA/JPL-Caltech)
On the Martian scale, InSight was relatively close to the epicenter (2,250km). According to Philippe Lognonné, scientific manager of the SEIS instrument at IPGP and professor at Université Paris Cité: “This short epicentral distance and the very high magnitude explain the magnitude of the signal, and the fact that both the volume and surface waves are so clear. In a way, this earthquake is a gold mine for not only confirming our internal structure models, but also improving them! The event also took place very early in the morning on Mars, before dawn brought its share of atmospheric disturbances: all the right conditions for the SEIS seismometer and its Very Broadband sensors to obtain high-quality results.
It is still too early to explain the nature of this earthquake. “Thanks to this earthquake, scientists will certainly benefit from essential information to unlock the secrets of the Red Planet’s interior. The operational teams are fully committed to ensuring that this highly sensitive seismometer can record high-quality data for as long as possible, so that if Mars ever speaks to us again, we’ll be ready to listen” reminds Charles Yana, Insight/SEIS project manager at CNES.
As the icing on the cake, the engineers on the SEIS team were able to transcribe the earthquake into audio for a more immersive experience: “To do this, we removed the resonant frequency of the SEIS instrument and eliminated the glitches (or peaks in the signal). These ‘glitches’ are generated by the cable linking the SEIS instrument to the InSight lander,” explains Rémi Lapeyre, head of Insight/SEIS operations at CNES. It was the experts at IPGP who developed this digital processing”. The resulting sound track then had to be amplified and accelerated 44 times to make it audible to the human ear. Finally, if you listen carefully, you’ll hear 2 tracks, not quite identical on the left and right, coming from the 3 sensors of the SEIS instrument: stereo effect guaranteed!
