Development of a NASA roadmap for planetary protection to prepare for the first human missions to Mars.

As part of planning for future space exploration, COSPAR (The Committee on Space Research) together with participating space agencies, organized and held interdisciplinary meetings to consider next steps in addressing knowledge gaps for planetary protection for future human missions to Mars. Beginning with the results of these meetings and earlier work by NASA, ESA, and COSPAR (e.g., Criswell et al., 2005; Hogan et al., 2006; Rummel et al., 2008) as a base the authors of this paper carried out a follow-on NASA planning activity to identify the necessary steps to be accomplished to close knowledge gaps. We identified significant overlap between the planetary protection needs and other sets of Mars preparation roadmaps (1) microbial monitoring requirements for crew health and medical systems, (2) studies of the microbiome of the built environment, (3) environmental control and life support systems (ECLSS), (4) waste management, and (5) planetary surface operations. In many cases, efforts to mature exploration class systems for Mars that are occurring in other domains can be leveraged with minor changes to address planetary protection gaps as well. In other cases, work planned for testing on the International Space Station (ISS) as an analog for crew Mars transit, or on the lunar surface as an analog for Mars surface operations can be used to close planetary protection technology and knowledge gaps. An overall strategic framework that combines these domains has the advantage of being more comprehensive, efficient, and timely for closing gaps. This approach has led to the development of a NASA roadmap for addressing planetary protection integrated with other related roadmaps. NASA's development and execution of the planetary protection is now viewed in an integrated way with related technology development and testing. Key features of the integrated capabilities roadmap include.

Deposition of extreme-tolerant bacterial strains isolated during different phases of Phoenix spacecraft assembly in a public culture collection.

Extreme-tolerant bacteria (82 strains; 67 species) isolated during various assembly phases of the Phoenix spacecraft were permanently archived within the U.S. Department of Agriculture's Agricultural Research Service Culture Collection in Peoria, Illinois. This represents the first microbial collection of spacecraft-associated surfaces within the United States to be deposited into a freely available, government-funded culture collection. Archiving extreme-tolerant microorganisms from NASA mission(s) will provide opportunities for scientists who are involved in exploring microbes that can tolerate extreme conditions.

Atmospheric entry simulations of Mars lander bioload--experiments in support of Beagle 2.

Simulations of the temperature and vacuum effects of Martian atmospheric entry upon Bacillus atrophaeus (formerly Bacillus subtilis var niger; 8058; NCIMB) endospores were carried out inside a purpose-built vacuum chamber. The work formed part of the study in support of planetary protection for the Beagle 2 Mars lander and investigated to what extent the outer surface of the lander's back heat shield would be sterilised during Mars atmospheric entry. The spores were heated to peak temperatures up to 300 degrees C over 30 s under vacuum conditions (10(-3) mbar). There was no effect on spore viability until peak temperatures reached 180-200 degrees C (12-15 s of heat exposure). Spore viability then fell rapidly with increasing temperature. Once peak temperatures exceeded 300 degrees C, no further spore viability was detected. The average heating rate was rapid (10 degrees C s(-1)); thus spores were exposed to peak temperatures for less than a second. These data inform on the process of determining bioburden reduction and control steps necessary for external surfaces of spacecraft which are non-sterile at launch, as well as providing new information about the ability of a model resistant organism to survive rapid, short-duration heating.