Bio-Barriers: Protecting Extraterrestrial Bodies and Exploration Instruments from Terrestrial Microbiological Contamination

A small team of engineers at the Jet Propulsion Laboratory (JPL), California Inistitute of Technology (CalTech) have developed a unique capability to control terrestrial microbial contamination on instruments to be used for detection of biosignatures on extraterrestrial bodies during exploration missions. The team has developed bio-barrier designs to enclose instruments during sterilization process and to protect them from subsequent recontamination until such instrument arrives at its destination. Once there, the bio-barrier would deploy to allow the instruments to perform their function. Two types of bio-barrier designs were considered; one for dry heat microbial reduction application and the other for vapor hydrogen peroxide application. For both applications, extensive material testing was performed to select the bio-barrier material. Detailed mechanical design, including environmental analysis, was performed to produce the prototype hardware for both designs. Environmental and deployment testing were also performed using the prototype. One of the bio-barrier designs has been adopted for flight application by the upcoming Mars Scout Phoenix '07 mission. The results of these technology development studies provide the foundation for a new paradigm for low mass, low cost, planetary protection/ contamination control mechanisms that focus on protecting particular instrument elements rather than entire spacecraft hard shell barriers as done during the Viking program.