Section 6 of the SR-SAG2 report addresses the implications and opportunities of the identification of Special Regions for human Mars missions. The review committee noted that the impact of human spaceflight on planetary protection, in general, and Special Regions, in particular, had not been considered with the same rigor and thoroughness that had been applied to other parts of the SR-SAG2 report. Even though planning for human missions to Mars is in its infancy, the committee believes than the planetary protection implications of sending astronauts to Mars raises profound questions at the intersection of science, engineering, technology, project management, and public policy. The committee recognizes that the SR-SAG2 report was not the place to address and/or resolve these issues. However, a greater emphasis that the issues exist was warranted.1 Compounding this lack of emphasis, some statements made in the human exploration section of the SR-SAG2 report are inconsistent with other parts of the document. Examples of such inconsistencies include the following:
- The first sentence in Section 6.1.1 (Water resources) states: “The polar caps (between ~80° and 90° latitude in each hemisphere) would be the major reservoir of H2O that can be accessed by human explorers and would not be considered to be Special Regions.” This suggests that all locations in the polar cap will not be Special Regions. Sufficient examination of the polar cap has not been accomplished to support this statement. In addition, no mention is made of the possibility of Special Regions being induced by modification of the environment by spacecraft or human explorers.
- The second to last sentence in Section 6.1.1 states: “Therefore, other than the RSL sites and possibly active gullies, no location within the equatorial zone is considered Special.” As identified above, sufficient examination of all locations within the equatorial region has not been accomplished to support this statement. In addition, the statement itself does not recognize other features such as caves and thermal zones identified within the report that may exist within this region. This can lead to misunderstandings by future mission planners who are considering missions to these areas.
1 The committee notes that the planetary protection community has taken some initial steps to address issues relating to the human exploration of Mars. The website of the March 2015 meeting “Human Missions & Planetary Protection: Workshop on Planetary Protection Knowledge Gaps for Human Extraterrestrial Missions,” http://planetaryprotection.nasa.gov/humanworkshop2015/, contains a useful summary of relevant issues and current activities.
Moreover, some of the language used to describe the systems required for human missions can be interpreted to mean that human missions will not be required to follow the COSPAR planetary protection requirements, even if in the actual COSPAR policy it is explicitly stated: “The intent of this planetary protection policy is the same whether a mission to Mars is conducted robotically or with human explorers. Accordingly, planetary protection goals should not be relaxed to accommodate a human mission to Mars” (COSPAR 2015, p. 14).
The review committee also noted that this section does not include any findings. This is inconsistent with earlier sections of the report and misses the opportunity to solidify the importance of the COSPAR planetary protection requirements. The committee proposes a finding for this section.
New Finding 6-1: Human missions to Mars are required to fully follow the planetary protection requirements specified by COSPAR, including the limitations specified for Special Regions. This may prevent humans from landing in or entering areas that may be Special Regions or may become Special Regions through modifications of the environment by space systems and/or human explorers.
Finally the committee recognizes that human spaceflight systems operate differently than robotic systems. Understanding the implications of humans on Mars and the ability of human systems to meet COSPAR requirements is essential to ensuring that nations can continue to conduct science investigations without worrying that these human systems have contaminated places where science is being conducted.
Suggestions for future research directions relating to the issues discussed in this section can be found in Appendix A.