The Scientific Mission PICARD – the opérationnal aspects
E. Aitier1, M. Anciaux2, F. Duchevet1, A. Hauchecorne3, J.F. Hochedez3, A. Irbah3, M. Meftah3, C. Queirolo2, 
M. Rouzé1, A.J. Vieau3


PICARD is an investigation dedicated to the simultaneous measurement of the absolute total and spectral solar irradiance, the diameter and solar shape, and to the Sun's interior probing by the helioseismology method. The satellite was launched on June 15th, 2010 for a life expectancy of 2 years; its scientific operational mission ended in March, 2013.
The control of the operations in orbit was made by the PICARD ground component, which was constituted by two components 
* the Command Control Ground Segment, the MIGS (MIcrosatellite Ground Segment), implemented in CNES, Toulouse, and including in particular the Command Control Centre (CCC) and the CNES network of 2 GHz emission and reception Stations,
* The PICARD Scientific Mission Centre (CMS-P) located at the BUSOC in  Brussels, mainly dedicated to the processing and the archiving of the payload data, as well as the programming of the payload,
To these entities was added the PICARD Scientific Expert Centres divided within the three laboratories in charge of the instruments development namely LATMOS (France) for SODISM, IRMB (Belgium) for SOVAP, PMOD (Switzerland) for PREMOS, and CERGA (OCA) for operations and data processing of the ground based instruments. Those Centres had mainly the role to achieve a high quality analysis of the instruments functioning, and the elaboration of the finalized calibrations and of the precise scientific results.
Very early at the beginning of the mission, SODISM and SOVAP instruments did not work according to the scientific needs of the mission. PICARD is a microsatellite, and it had to satisfy development and operational constraints that will be presented in the first part the presentation. 
The way of functioning of the payload and the ground segment had to evolve in the course of mission. Principles of functioning initially defined had to be revised and adapted to the degradation context of the mission. So we will focus on these aspects in the second part of the presentation.
This experience feedback was at the origin of the process of an “operational concept” definition for the future scientific missions, as for the fundamental physics mission MICROSCOPE. This concept will be presented in conclusion of the presentation.


1 CNES : French Space Agency- 18, Avenue Edouard Belin - 31401 Toulouse CEDEX 9, FRANCE
2 IASB : Belgian Institute for Space Aeronomy, 3 Avenue Circulaire, B-1180 Bruxelles, BELGIQUE
3LATMOS : Laboratoire Atmosphères, Milieux, Observations Spatiales, CNRS - Université Paris VI & Université de Versailles Saint-Quentin-en-Yvelines - IPSL, F-78280, Guyancourt, FRANCE



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Modèle de document par défaut CNES version 2.0 Janvier 2010 Normal1