SEIS: Overview, Deployment, and First Science on the Ground

The 50th Lunar and Planetary Science Conference in The Woodlands, Texas, March 18–22, 2019.Introduction: The InSight mission landed on Mars on November, 26, 2018. This is the first planetary mission designed to deploy a complete geophysical observatory on Mars, following in the footsteps of the Apollo Lunar Surface Experiments Package (ALSEP) deployed on the Moon in the 1970s [1]. It will thus provide the first ground truth constraints on interior structure of the planet. The Seismic Experiment for Interior Structure (SEIS) [2] is one of three primary scientific investigations, the others being the Heat Flow and Physical Properties Package (HP3) [3] and the Rotation and Interior Structure Experiment (RISE) [4]. SEIS is supported by the APSS package, (Auxiliary Payload Sensor Suite, [5]), whose goal is to document environmental sources of seismic noise and signals, as well as an imaging system [6]. After a brief description of the SEIS experiment, we will describe the deployment process, including the evolution of the SEIS noise from the deck (with only SPs) to the ground (with both VBBs and SPs), first without and finally with wind shield. We will then discuss early scientific observations, providing first constrains on the Mars micro-seismic noise, atmospherically-generated seismic signals, and surface and subsurface elastic structure.The SEIS team acknowledge the supports of NASA, CNES, UKSA, SSO and DLR for the experiment funding and of the SEIS operation team [38] for delivering SEIS data