Nasa’s InSight Mars lander has detected signals of what could have been a marsquake. The signals were recorded on 6 April and if confirmed would be the first detection of seismic activity on Mars.
Although the signals are only faint, they fit the profile of moonquakes that were detected with seismometers left on the lunar surface by the Apollo astronauts 50 years ago. The apparent marsquake produced readings that were bigger than the shaking of the spacecraft due to the martian wind, but smaller than the vibrations caused by the movement of the spacecraft’s robotic arm.
Even fainter signals of possible marsquakes were recorded on 14 March and 10 and 11 April. On Earth, signals of this size would not even be detected against the background of seismic noise generated inside our planet every day.
InSight landed on Mars on 26 November 2018 and deployed the seismometer a few weeks later. The Seismic Experiment for Interior Structure (SEIS) was designed and produced by CNES, the French space agency. As well as marsquakes, SEIS is designed to detect the impact of meteorites and the vibration of the martian surface in response to weather phenomena such as martian dust storms.
