Spatial environment: specification and consideration

The environment is one of the several constraints to take into account for carrying out efficient spaces programs. The evaluation of this environment is the task of the 'Space Environment' Department of ONERA. This paper describes shortly this environment which its cumulative and sporadic effects. Two examples are developed: impacts with micro-meteoroids and micro-debris and micro-meteoroids and micro-debris and the consequences of radiations on electronics components. Special attention is given to the 'Active Pixel Sensor' (APS) set up in SupAero. (authors)