Proposed by NASA's Jet Propulsion Laboratory, InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) is the first Martian geophysical observatory. Its objective is to precisely determine the internal structure of the red planet, to shed light on the formation and evolution processes of the telluric planets of the solar system.
Using a robotic arm, the InSight lander will drop two main instruments on the ground: a six-axis seismometer under French responsibility, SEIS, and a heat flow sensor, HP3, provided by Germany. The probe also carries a set of auxiliary sensors (meteorological station, magnetometer, radiometer) that will be used not only to remove the disturbing influence of the environment from seismic signals, but also to perform scientific measurements. Finally, the two radio antennas of the RISE geodetic experiment will be used to measure the rotation of the planet Mars as precisely as possible.
Financed by CNES, the SEIS instrument is a very complex instrument that has benefited from extensive international collaboration. The instrument is structured around three very wide band clocks, developed in France by the technical and scientific teams of CNES, IPGP, Space Campus of Université Paris Diderot and the industrial company SODERN. Equipped with a high resistance, to be able to cope with the constraints of the space environment, these sensors are also highly sensitive. They will make it possible to measure soil displacements at the atomic scale.
By listening to how seismic waves, caused by Martian earthquakes or meteorite impacts, will propagate inside Mars, geophysicists are going to determine for the first time precisely the structure of the planet, from the crust to the metallic core, via the mantle. InSight will also measure Martian seismicity, meteorite impact rates, and the power dissipated in space by the planetary engine (thanks to HP3).
Artist's view of the internal structure of Mars (© IPGP - David Ducros)
All informations about planetary seismology, the InSight mission and the SEIS instrument are available on the special website: https://www.seis-insight.eu/en