A very broad band 3 axis seismometer to study internal structure of Mars

Very Broad Band seismometers are the best instruments for studying internal structure of telluric planets [1]. Development of such instrument dedicated to Mars observation take up a real instrumental challenge. In fact they must be able to : detect ground displacement of a few 10 pm in a bandwidth from DC to 20 Hz in the 3 directions, have a very low sensitivity to temperature, pressure, gravity... be installed automatically on any ground, have a low mass ( < 2 kg with the installing devices) a low volume and low power consumption ( < 1 W), resist to landing shock, usually close to 200 g. Such instrument [2] have been developed by IPGP and INSU, with the industrial collaboration of SODERN, under an R&D contract from CNES. It will be part of each lander of the Netlander mission, which plan to deploy 4 small stations on Martian ground in 2006, to perform a geophysical study of this planet.