a better understanding of environmental processes on each planet. In addition, R&A programs also must address the need for basic understanding of the interplay between organisms and their geological environments, the nature of biosignatures, and the astrobiology of Mars.
In addition to preparing for the next generation of missions and the science objectives to be addressed by them, ongoing analysis and investigation put the science community in a better position to understand the nature of the questions that are being asked or the results that are being obtained. Because the education and the training of scientists, engineers, and managers who will work on the next generation of missions are funded through the R&A and technology programs, the health of those programs is vital to the development of a future workforce.
Recommendation. Continued strong support of NASA’s basic research and analysis programs is an essential investment in the long-term health of the Mars Exploration Program.
Analysis of martian meteorites has been central to the development of the current understanding of Mars, its potential for life, and ideas about detection of present or fossil life. It continues to be essential to developing ideas and protocols relevant to analyzing samples that are pertinent to astrobiology and life-detection science goals. It is especially important to search for martian meteorites that formed during early periods of Mars’s history, as well as meteorites of sedimentary origin. This is an important area of collaboration between NASA and the National Science Foundation.
Recommendation. Collection and analysis of martian meteorites must continue, even though biases in the compositions and ages of these meteorites, their uncertain provenance, and the effects of impact-ejection and transfer to Earth mean that they cannot take the place of samples returned from Mars.
As with the analysis of martian meteorites, studies of Mars-analog sites are essential to mission development and execution and to the training of the scientists engaged in current and future missions. Such studies focus on the technological aspects of missions and not on the development of basic scientific concepts regarding how life behaves and leaves signatures. Studies of Mars-analog sites on Earth should continue to be a fundamental aspect of Mars astrobiological research because they provide critical understanding of Mars-like environments for the testing and development of instrumentation and sample-handling protocols; understanding that supports the development and validation of techniques for detecting and measuring biosignatures, including establishing baseline abiotic signatures; and discovery of novel organisms and metabolisms and the chemical/isotopic imprints of these metabolisms on Mars-like environments.
Recommendation. Terrestrial analog studies should include testing instrumentation, developing techniques for measuring biosignatures under Mars-like conditions, and conducting technological proof-of-concept studies.
What approaches to the exploration of Mars will maximize the astrobiological science return? The astrobiology science goals for Mars are extremely broad. They legitimately include determining the volatile inventory of the planet upon formation and the evolution of volatiles through time, the geological and geophysical evolution of the planet, the interplay between the geology and the atmosphere and the history of habitability, and, of course, the determination of whether there is life today or has been life at some time in the past. As researchers learn more about Mars, they are finding that there is an incredible diversity of local and regional environments—as exemplified by the landing site of the rover Opportunity—that have chemical properties and physical implications that are very different from what had been expected. There clearly is the potential for identifying an incredibly diverse range of properties as more is learned about more places in detail via remote sensing and in situ analysis. Thus, any astrobiological exploration of Mars has to take into account the incredible diversity of Mars, as well as the diversity of questions that bear on the issues.