Planetary protection requirements for orbiter and netlander elements of the CNES/NASA Mars sample return mission

Abstract In the framework of Mars exploration, particularly for missions dedicated to the search for life or for traces of ancient forms of life, NASA and CNES have decided to join their efforts in order to build a Mars sample return mission. Taking into account article IX of the OUTER SPACE TREATY (Treaty on principles governing the activities of states in the exploration and use of outer space, including the Moon and other celestial, referenced 610 UNTS 205 - resolution 2222(XXI) of December 1966, ratified in London / Washington January 27, 1967) and in order to comply with the COSPAR planetary protection recommendations, a common planetary protection program has to be established. Mars in-situ experimentations are limited by the size and the mass of the instruments necessary to perform exobiology investigations and, consequently, it appears that the best way to conduct such experiments is to bring back Mars samples to Earth. A sample return mission enables the use of a very large number of instruments and analysis protocols, giving exobiologists the best chance to find living entities or organic compounds related to life. Such a mission is complicated from a planetary protection point of view, it combines constraints for the protection of both the Mars environment as well as Earth, including the preservation of samples to ensure the validity of exobiological experiments.