Planetary Protection Knowledge Gaps and Enabling Science for Human Mars Missions

Abstract

In the coming decade, as we prepare for the first mission to Mars with a human crew, we have a continuing obligation to protect the integrity of scientific investigations at Mars. In particular, it is unlikely that the search for life on Mars will be completed by the time the first crew systems arrive at the martian surface. Indeed, some consider the presence of astronauts to be an essential augmentation to the robotic search for evidence of life on the red planet. In addition, the environment of the Earth needs to be protected from the threat posed by the uncontrolled release of a putative martian life form into the terrestrial biosphere. Prevention of such harmful cross-contaminations between Mars and the Earth is the practice of planetary protection. At present, the knowledge of how to achieve these two goals (prevention of forward contamination from Earth and backward contamination from Mars) is well described for robotic systems. In contrast, for human missions there are only guidelines (Kminek et al. 2017a) but no engineering requirements, in part, because our knowledge of Mars (and of how contamination from crewed systems will interact with Mars) is incomplete. These gaps in our knowledge (as also described in NASA NID8715.129) need to be addressed through acquisition of new data during the next decade, if planetary protection measures are to be implemented successfully for human missions. This paper describes the technical issues and measurements needed.