The INSIGHT SEIS VBB Experiment
Abstract
The SEIS experiment is the primary payload of the Interior Structure investigation using Seismology and Heat Transport (INSIGHT) Mission Proposal, submitted to NASA in the frame of the 2010 Discovery program, and selected for a competitive phase A study, together with two other projects. The objective of the INSIGHT SEIS experiment is the determination of the deep internal structure of Mars. In particular, geophysical parameters of first importance, such as the state (liquid/solid) and size of the core, structure of the mantle, shape of discontinuities, thickness of the crust will be determined by the experiment. It will measure seismic activity in a very broad band of signal, from the tidal frequencies (0.05 mHz) up to the short period frequencies (50 Hz), to address the widest range of scientific questions, from the state of the core to the meteoritic impact and quake rates. The instrument integrates a Very Broad Band (VBB) 3 axis seismometer, completed by another trihedron of MEMS short period seismometers, environmental sensors for pressure, wind and temperature, The sensors will be deployed on the Martian ground by a robotic arm from a Phoenix-type lander platform and protected by a wind and thermal shield. The sensor assembly, which contains all seismic sensors, the leveling system, as well as house-keeping and temperature measurements, will be deployed on the soil in order to allow the best possible mechanical coupling with the ground motion. The wind and thermal shield, the sensors' specific containers (vacuum sphere for VBBs) and a passive thermal compensation system will achieve a very high protection of the VBB against temperature and pressure variations, allowing the sensor to operate in the rough Martian thermal environment while reaching a deection threshold below 10-9 ms-2 Hz-1/2 in the VBB bandwidth. A dedicated electronics will manage the overall experiment and ultra-low noise, space qualified 24 bits A/D converters will perform the acquisition. The proposed instrument has been developed up to PDR in the frame of the ExoMars Humbold payload in 2009, and further developments were achieved in the frame of the Japanese SELENE2 project and the phase A of the INSIGHT project. During the INSIGHT Phase A, Tests of the Earth version of the VBB have been performed in either low noise seismic vault, in the Black Forest Observatory, or in more realistic conditions under wind and thermal shield at the Reunion Island. Most critical parts have been thoroughly tested, and the qualification models are ready to be produced in case of selection. The INSIGHT phase A has ended in March 2012, and the final NASA continuation decision is due in August 2012. If selected, INSIGHT will be launched in 2016.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFM.P41A1881T
- Keywords:
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- 0994 EXPLORATION GEOPHYSICS / Instruments and techniques;
- 5430 PLANETARY SCIENCES: SOLID SURFACE PLANETS / Interiors;
- 6225 PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS / Mars;
- 7294 SEISMOLOGY / Seismic instruments and networks