FIGURE 4.1 Spirit rover’s robotic arm. SOURCE: NASA.



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FIGURE 4.1 Spirit rover’s robotic arm. SOURCE: NASA.

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4 Mars Mars OVERALL ASSESSMENT: Grade: A Trend: ➜ NASA’s exploration of Mars has been an outstanding example of a successful solar system exploration pro- gram, and for this reason the Committee on Assessing the Solar System Exploration Program assessed it with a grade of A with a steady trend, although the committee notes that NASA is currently considering making substantial changes to the Mars program that will require careful evaluation by the scientific community. The Mars Exploration Program (MEP) was restructured in 2000 after the failures of the Mars Climate Orbiter and Mars Polar Lander. Key in the restructuring was the recognition that to understand Mars as a system requires a set of interrelated missions in a coupled program.1 Such a program also requires supporting infrastructure, par- ticularly communications, so that the high-data-rate, high-bandwidth data from current and future missions can be successfully returned. Finally, a long-term technology investment is needed to develop the systems and subsystems for future missions of ever-increasing complexity. Another principle in the restructuring was to alternate orbital missions providing global context with landed “ground truth” projects to gradually reduce the number of potential sites for a sample return to a few high-inter- est scientific locations. This strategy has proven sound as the “Follow the water” theme combined the results of Mars Global Surveyor, Odyssey, and the Spirit and Opportunity rovers into solid scientific understanding of the history of ancient water. The committee identified two scientific threads in the MEP that support future missions. One thread addresses the long-deferred understanding of Mars’s atmosphere and the solid planet geophysics through aeronomy, clima- tology, and seismology. The other thread is a well-defined scientific and engineering path to obtain and return a well-characterized sample of Mars rock and soil. By “well-characterized” sample, the committee means that the sample should be of both geological and biological interest and must have preserved or recorded the context from which the sample was taken.2 The committee believes that NASA will need to engage relevant members of the Mars science community in the Mars Sample Return (MSR) planning process to ensure that a consistent definition of a “well-characterized” sample is employed by the program. 1G. Scott Hubbard, Firouz M. Naderi, and James B. Garvin, “Following the Water, the New Program for Mars Exploration,” Acta Astro- nautica 51(1-9):337-350, 2002. 2For further reference to current thinking about the sample return sites and locations, see National Research Council, An Astrobiology Strategy for the Exploration of Mars, The National Academies Press, Washington, D.C., 2007. 

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6 GRADING NASA’S SOLAR SYSTEM EXPLORATION PROGRAM The past or present biological potential of Mars will ultimately best be examined by many science teams using the full arsenal of laboratory instrumentation on a properly selected returned sample. The committee strongly encourages NASA to begin the investment and planning necessary to make an MSR mission a reality. After the committee had begun writing its report, it was informed of NASA plans to significantly alter the Mars Exploration Program with the primary goal of achieving a Mars Sample Return mission starting around 2020 (meaning returning the actual sample to Earth several years after that date). The committee addresses this subject at the end of this chapter and notes that in this report it only assessed NASA’s Mars performance to date and not the incomplete and preliminary plans for the Mars program that NASA is currently developing, even if they may substantially alter NASA’s progress in meeting the goals of the decadal survey. ASSESSMENT OF PROGRESS TOWARD MEETING MARS-SPECIFIC RECOMMENDATIONS MADE IN THE SOLAR SYSTEM EXPLORATION DECADAL REPORT New Frontiers3 Recommendation Results of Midterm Review Grade: A “The SSE Survey recommends that the Mars Scout program be managed as Trend: ➜ is the Discovery program, with principal-investigator leadership and competitive selection of missions.” (p. 200) NASA currently has one Mars Scout mission (Phoenix) under way to Mars and two missions (the Great Escape mission and the Mars Atmosphere and Volatile Evolution, or MAVEN, mission) in formulation competing for the second Scout opportunity in 2011. All three are principal-investigator (PI)-led and were selected through a com- petitive process. NASA has been doing an excellent job in initiating and implementing the Mars Scout program. New Frontiers Recommendations Results of Midterm Review “The SSE Survey strongly recommends that the Mars Exploration Program commit equally as strongly to the Scout program as to sample return.” (p. 200) Grade: A Trend: ➜ “The SSE Survey recommends that a Mars Scout mission be flown at every other launch opportunity.” (p. 200) The Phoenix mission is already flying in the first Mars Scout launch opportunity in 2007 and will be followed by either the MAVEN mission or the Great Escape aeronomy mission in the second launch opportunity in 2011 (subsequently delayed until 2013). The committee endorses the current plan that would ensure that Scout missions fly at every other launch opportunity and that NASA should continue to plan for an Announcement of Opportunity for a 2016 competed Scout mission.3 New Frontiers Recommendation Results of Midterm Review Grade: B Trend: ➜ “The SSE Survey recommends that while carrying out its science mission, the Mars Science Laboratory mission should test and validate technology required for sample return (e.g., sample handling and storage in preparation for sample return and feed-forward lander design, consistent with the future use of a Mars Ascent Vehicle).” (p. 200) A number of technologies that can and will be applied to missions in the next decade have been integrated into the Mars Science Laboratory (MSL) mission. In particular, the Skycrane and the MSL entry, descent, and landing system will provide technologies to the Astrobiology Field Laboratory (AFL), to a Mars Sample Return mission, and possibly to systems related to the human exploration of Mars (in which the risk of contamination of 3National Research Council, New Frontiers in the Solar System: An Integrated Exploration Strategy, The National Academies Press, Wash- ington, D.C., 2003.

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7 MARS samples is significantly greater than the risk from exploration by robots). Thus, the committee applauds NASA’s effort on entry, descent, and landing design; testing; and implementation for the MSL mission. Preparations for the MSL mission have also led to some advancements in surface sample handling. The MSL mission’s work on in situ sample handling has been productive and has demonstrated the challenges in obtaining, processing, and caching samples that meet scientific and planetary protection objectives. The committee encourages the Mars Exploration Program to use this experience to guide future technology development for the Astrobiology Field Laboratory and Mars Sample Return. New Frontiers Recommendation Results of Midterm Review Grade: C “The SSE Survey recommends that NASA begin its planning for Mars Sample Trend: ➜ Return missions so that their implementation can occur early in the decade 2013- 2023.” (pp. 7, 198) Mars Sample Return has long been a high priority for the planetary science community, as was reflected in the decadal survey. Some early preparations for MSR have been facilitated by the MSL mission (advancements in entry, descent, and landing and in surface sample acquisition and sample handling). Additional preparations will likely be facilitated by the AFL mission (sample caching and handling, sterilization, and precision landing). Nevertheless, the committee found that MSR-specific planning and preparation activities are not occurring and that an MSR mission has been pushed beyond the time frame specified in the decadal survey. Over the next year (2007-2008), the Mars Exploration Program plans to, and should, charter a technology assessment group to priori- tize the technology developments needed in the next 10 to 15 years to enable a sample return mission. Technology advancements required for MSR, and indeed other upcoming Mars missions, have been seriously eroded by recent reductions in research and technology programs. The specific programs under stress are the Planetary Instrument Definition and Development Program (PIDDP), the Mars Instrument Development Project (MIDP), Astrobiology Science and Technology Instrument Development (ASTID), Astrobiology Science and Technology for Exploring Planets (ASTEP), and the Mars Technology Project (MTP). While NASA has shown strong leadership in the long-term implementation of Mars Sample Return, no single individual currently has oversight of a future MSR mission as his or her primary responsibility. MSR will contain several tightly coupled major projects (orbital rendezvous spacecraft, Mars Ascent Vehicle, Sample Return Vehicle, and others). The committee expresses serious concern that sample return will not be possible in the next decade under the current investment environment. MSR planning and preparation will need significant attention in the next solar system exploration decadal survey. Recommendation: NASA should begin actively planning for Mars Sample Return, including precursor missions that identify and cache well-characterized samples of both geological and biological interest. New Frontiers Recommendation Results of Midterm Review Grade: B “The SSE Survey recommends that NASA engage prospective international Trend: ➜ partners in the planning and implementation of Mars Sample Return at an early stage in order for this complex mission to benefit fully from the capabilities and resources offered by the international community.” (p. 201) The committee notes that international participation has proven beneficial for recent Mars missions and encour- ages the Mars Exploration Program to continue to pursue opportunities for international participation for future missions. Notably, the MEP should continue to actively pursue partnering with the European Space Agency’s (ESA’s) Aurora Program, which has a Mars sample return element planned for late in the next decade. The MEP should also continue to work through the International Mars Exploration Working Group (IMEWG) to begin broader international MSR studies. The committee emphasizes the need for the IMEWG and NASA to obtain a consensus in time for the preparation of future budgets to allow the MSR mission to proceed expeditiously. Con- sidering the complex nature of a sample return mission, international partners may be necessary in order to make

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 GRADING NASA’S SOLAR SYSTEM EXPLORATION PROGRAM this mission affordable under current program budget out-year expectations. The committee also believes that an analysis of the interface issues and a realistic cost and risk assessment should precede any formal international agreements regarding an MSR mission. New Frontiers Mars-Specific Recommendation Results of Midterm Review Grade: C “The SSE Survey recommends that well before cosmic materials are returned Trend: ➜ from planetary missions, NASA should establish a sample-analysis program to support instrument development, laboratory facilities, and the training of researchers.” (p. 9) The committee found little progress toward establishing a sample analysis program that supports instrument development, analytical facilities, and researcher training as preparation for MSR, and yet cosmic materials have already been returned in the Stardust and Genesis missions. Past progress on a sample-handling/sample-receiving facility for the quarantine, characterization, curation, and distribution of returned Mars samples has stalled. In preparation for Mars Sample Return, NASA should work with the Mars Exploration Program Analysis Group (MEPAG) and the broader astrobiology/exobiology research community to assess the current state of the art in laboratory analysis instruments, identify where further development would be beneficial for Mars sample analysis and biosignature detection, and verify that the needed instruments and laboratory facilities will be made available as part of the sample-handling facility as soon as samples are returned. As the state of the art advances, these assessments should be periodically reevaluated. Lastly, the establishment of a vigorous scientific community and the development of advanced skills needed to analyze Mars samples will require the training of young researchers in the decades before MSR. The severe budget reductions in astrobiology/exobiology have stalled research activities and have had a profoundly negative effect on early-career scientists who will be the leaders in future Mars missions. The committee believes that astrobiol- ogy/exobiology will likely play heightened and critical roles in the development of advanced instrumentation in future landed Mars missions. Recommendation: NASA should begin consulting various groups such as MEPAG and the astrobiology/exo- biology research community to assess the current state of the art in laboratory analysis instruments, identify where further development would be beneficial for Mars sample analysis and biosignature detection, and verify that the needed instruments. laboratory facilities, and new researcher training will be made available as part of the sample-handling facility as soon as samples are returned. 4 PROGRESS TOWARD MEETING RECOMMENDATIONS MADE IN ASSESSMENT OF NASA’S MARS ARCHITECTURE 2007-2016 Mars Architecture4 Recommendation Results of Midterm Review Grade: B “In addition, planetary protection requirements for missions to worlds of biological Trend: ➜ interest will require investments, as will life-detection techniques, sample quarantine facilities, and sterilization technologies.” (p. 45) Planetary protection is critical for the preparation and successful implementation of landed Mars missions, including the MSL and the proposed AFL and Mars Sample Return missions. As future landed missions become more capable and focus on the search for biosignatures, planetary protection measures will become even more important. The committee applauds past NASA investments in planetary protection research and analysis (R&A) that have led to current capabilities in the rapid quantification of spore counts on spacecraft materials. As empha- sized in the NASA Research Announcement entitled “Research Opportunities in Space and Earth Sciences (ROSES) 4National Research Council, Assessment of NASA’s Mars Architecture 2007-2016, The National Academies Press, Washington, D.C., 2006.

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 MARS 2006,” planetary protection should incorporate sophisticated molecular biological approaches (for example with lab-on-a-chip and genomics technologies—i.e., the ability to detect the fingerprints of life, or the presence of biological signatures that are carried in the genetic material of all living things) to significantly improve capabili- ties. The committee finds, however, that the current funding level for R&A with respect to planetary protection is inadequate to make these important, and costly, advancements. A sophisticated search for biosignatures on Mars will require significant advancements in the knowledge of biomarkers in cultured and uncultured microorganisms, in extreme environments, and in Earth’s geologic record. Indeed, early-Earth materials may provide some of the best Earth analogues for testing and refining biosignature detection capabilities for Mars missions. Such efforts in basic research will require significant investments in R&A, in laboratory equipment, in instrument development, and in the training of young researchers. At the same time, the committee found that budget reductions in ASTID, ASTEP, PIDDP, and MIDP have significantly curtailed the ability to develop new analytical approaches and instruments for biosignature detection on upcoming Mars missions. The committee is seriously concerned that progress in U.S. capabilities for spacecraft bioload characterization, biosignature detection, and analytical instrumentation will stall. A comprehensive study, which involved three independent industry groups, on a sample-handling/sample- receiving facility for the quarantine, characterization, curation, and distribution of returned Mars samples has been completed under the direction of the Mars Exploration Program. However, the committee found that progress on this facility was stalled once NASA made the decision to delay MSR until the third decade (beyond 2023). In the Mars Sample Return-Mars Returned Sample Handling Facility science roadmap provided to the committee, it is clear that up to 12 years of funding and preparation are necessary before a sample is returned to Earth. In order to proceed effectively with a Mars Sample Return program, NASA will need to resume progress on developing this facility as soon as possible. Mars Architecture Recommendation Results of Midterm Review Grade: B “Include the Mars Long-Lived Lander Network in the mix of options for the 2016 Trend: ➜ launch opportunity.” (p. 2) The committee notes that the long-recommended landed network mission has been included as an option for a 2016 launch, and NASA therefore has complied with the recommendation qoted above. Furthermore, the 2016- 2018 Science Analysis Group (SAG) was initiated in July 2007 to address questions about the Long-Lived Lander Network. The committee encourages the ongoing engagement of community-based SAGs for mission analysis and definition. However, the committee is concerned that the continued study of options may not result in a decision and also notes that certain technologies required for networks have not yet been developed; therefore, it cannot award this subject the highest grade, but awards it a grade of B. The committee believes that innovative thinking such as carrying long-lived landed science packages on the proposed 2013 Mars Science Orbiter is a way to reach a second-decade mission queue that maximizes scientific return while also providing much-needed communica- tions infrastructure. However, late in its deliberative process, the committee received information from NASA implying that the Mars Long-Lived Lander Network may be removed from the Mars Exploration Program entirely. The committee assesses a downward trend because of this information. Mars Architecture Recommendation Results of Midterm Review Grade: A Trend: ➜ “Consider delaying the launch of the Astrobiology Field Laboratory until 2018 to permit an informed decision of its merits and the selection of an appropriate instrument complement in the context of a mature consideration of the results from the Mars Science Laboratory and other prior missions.” (p. 2) As with the lander network mission, NASA is considering delaying the Astrobiology Field Laboratory mission, thus meeting the letter of the decadal recommendation. However, the committee is concerned that if the only activ- ity is a study by a SAG, this will not lead NASA to a definitive conclusion regarding AFL delay. The committee

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0 GRADING NASA’S SOLAR SYSTEM EXPLORATION PROGRAM notes that a decision on when to proceed with the AFL mission will require a program-level analysis that includes multiple considerations: (1) the science will focus on a scientific hot spot with a high probability of examining a habitable zone, (2) the technology and instruments are ready for biosignature detection, and (3) the mission can provide a good start on MSR, possibly even caching samples for MSR. The prime consideration will be to balance these maturity considerations with the need for in situ biological characterization prior to MSR and to maintain the momentum supplied by Spirit and Opportunity, Mars Science Laboratory, and the ESA’s Exo-Mars spacecraft. Mars Architecture Recommendation Results of Midterm Review Grade: A Trend: ➜ “Establish science and technology definition teams for the Astrobiology Field Laboratory, the Mars Science and Telecommunications Orbiter [name now changed to Mars Science Orbiter], the Mid Rovers, and the Mars Long-Lived Lander Network as soon as possible to optimize science and mission design in concert with each other.” (p. 2) The committee again applauds the Mars Exploration Program for its use of science definition teams (SDTs) and SAGs. This process is very useful in obtaining the sense of the community and establishing a range of options. The committee’s understanding is that a SAG will look at the 2016-2018 period and its results will feed into a more focused SDT to set the scope of the missions for Announcement of Opportunity competition in an appropri- ate time frame. Mars Architecture Recommendation Results of Midterm Review Grade: C “Devise a strategy to implement the Mars Sample Return mission, and ensure Trend: ➜ that a program is started at the earliest possible opportunity to develop the technology necessary to enable this mission.” (p. 2) The committee notes that despite lacking a strategy to implement the Mars Sample Return mission, NASA has made some progress in developing some of the necessary technologies. For example, the committee lauds the close interaction between NASA and the Defense Advanced Research Projects Agency (DARPA) Orbital Express experiment that may provide technology for the autonomous rendezvous system. However, the committee is con- cerned that while some individual components of an MSR mission are being addressed, the overall strategy is not apparent. NASA’s lack of visible resources dedicated to the project is the basis for the committee’s downward trend assessment. The committee notes that reaching the best sites on Mars may be challenging. The ultimate benefit of a well- selected and well-characterized sample return justifies the development of long-lead-time technologies and the implementation of the mission either through international collaboration or through changes in NASA funding priority. The committee is encouraged to learn that NASA will assess compartmentalizing Mars Sample Return into manageable components to spread the risks and cost over several launch opportunities and permit substantive and separable contributions from international partners of the United States. NASA is making progress in the technology areas of medium and deep drilling, soil scoops, and coring, and in the entry, descent, and landing of the Skycrane. Previous efforts yielded good initial designs for the sample return capsule. However, the committee has learned that little recent progress has been made on the Mars Autonomous Vehicle or the quarantine facility. The lack of applied resources and dedicated effort to MSL science and technol- ogy development bodes poorly for reaching the goal of a mission in the next decade. Recommendation: NASA should begin robust technology investment aimed at reducing the risk associated with the four major engineering challenges of a successful Mars Sample Return, that is, the definition, design, and development of the following: 1. A Mars sample-receiving facility that can serve to certify the samples as safe for distribution; 2. A sample return vehicle that can provide a high probability of successful sample return to Earth

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1 MARS consistent with the guidelines from the NASA planetary protection officer and the Committee on Space Research (COSPAR); 3. Autonomous on-orbit rendezvous and docking capability at Mars for sample transfer and return; and 4. A Mars ascent vehicle that is capable of being transported to Mars, landing, and returning cached samples to Mars orbit. SCIENCE RETURN FROM CURRENT ARCHITECTURE Mars Architecture Recommendation Results of Midterm Review Grade: C Trend: ➜ “Develop and articulate criteria for distinguishing between the three options for missions to launch in 2016. Similarly, define a strategy that addresses the short lead time between science results obtained from the Mars Science Laboratory and selection of the mission to fly in 2016.” (p. 2) The committee applauds the diligence with which NASA is employing community-based information through the 2016-2018 Science Analysis Group process. However, consistent with the decadal survey recommendations, the committee strongly encourages NASA to make near-term decisions and to adopt a mission queue for the 2010- 2020 decade that leads to an MSR mission early in the 2020-2030 decade. The lack of a clear-cut decision thus far and the uncertainty of an unambiguous outcome place this item on an uncertain trend. It is worth noting that the trend and the grade of C are only a midterm assessment and may be improved greatly over the coming months. Given the average of 8 years for development from scientific measurement concept to Mars mission imple- mentation, the 2008 budget needs to address the project selection for the next decade. Recommendation: NASA should take all of the scientific, programmatic, and technical information avail- able and make a decision on a mission queue that includes the 2016 and 2018 Mars launch opportunities. Mars Architecture Recommendation Results of Midterm Review Grade: B Trend: ➜ “Clarify how trade-offs involving mission costs versus science were made for the various launch opportunities to justify the rationale behind the proposed sequence of specific missions and the exclusion of others.” (p. 2) While reviewing the progress thus far in planning, defining, and executing missions that cover the time period from 2003 to 2023, the committee found mixed results. NASA has made good progress for missions from 2003 to 2011. However, NASA’s progress in clearly defining the mission set beyond a Scout mission in 2011 is less encouraging. The committee is concerned about the uncertainty of future planning and outcomes and assigns a trend assessment that, although stable, is uncertain. Mars Architecture Recommendation Results of Midterm Review Grade: A “Maintain the Mars Scouts as entities distinct from the core missions of the Mars Trend: ➜ Exploration Program. Scout missions should not be restricted by the planning for core missions, and the core missions should not depend on selecting particular types of Scout missions.” (p. 2) The committee applauds the consistency of the Mars Exploration Program in maintaining Scout missions as distinct entities, now and in the future. Scouts remain an important element in Mars exploration and will continue to bring innovative ideas for exploration at modest cost. The committee hopes that NASA will maintain cognizance of the goals and objectives of both future core missions and selected or solicited Scout missions so as to encourage that they are complementary and avoid duplication.

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2 GRADING NASA’S SOLAR SYSTEM EXPLORATION PROGRAM Mars Architecture Recommendation Results of Midterm Review Grade: B Trend: ➜ “Immediately initiate appropriate technology development activities to support all of the missions considered for the period 2013-2016 and to support the Mars Sample Return mission as soon as possible thereafter.” (p. 2) The committee has noted that a defining characteristic of a highly coupled program such as the Mars pro- gram is the necessity of investing continually in the development of technologies that enable future missions in an interdependent queue. The committee is pleased to see that the Mars Exploration Program plans to charter a technology assessment group (TAG), which will include broad science-and-technology community involvement, to prioritize the technology developments needed for the next 10 to 15 years. The committee’s assessment reflects NASA’s good work and intentions to get the technology program back on track. However, the committee also notes that study alone is not sufficient. BALANCE IN CURRENT ARCHITECTURE Mars Architecture Recommendation Results of Midterm Review Grade: A Trend: ➜ “If the Mars Long-Lived Lander Network cannot be implemented in the period [2007-2016] under consideration, provide for an effort to make some of the highest-priority measurements on the landed missions that are included in the proposed Mars architecture.” (p. 3) As stated above, the committee finds that the long-recommended lander network mission has been included as an option for a 2016 launch, and thus a grade of A is justified. Furthermore, the 2016-2018 Science Analysis Group was initiated in July 2007 to address these questions. The committee hopes that NASA continues to use the community-based SAGs for mission analysis and definition. As always, such information is most useful when timed to match the federal budget cycle and agency planning. Mars Architecture Recommendation Results of Midterm Review Grade: A “Ensure that the primary role of the Mars Science and Telecommunications Trend: ➜ Orbiter [name now changed to Mars Science Orbiter] is to address science questions, and not simply to serve as a telecommunications relay. This distinction is particularly important with respect to the required orbital parameters that are adopted.” (p. 3) Following the loss of two spacecraft late in the last decade, the Mars Exploration Program was restructured to emphasize tightly coupled, science-driven strategic missions with supporting infrastructure, along with community based PI-led Scout projects. Given this basic strategic approach and the high data rates generated by current and proposed instruments, ongoing high-bandwidth telecommunications via a relay orbiter is a very high priority and therefore an integral part of the 2013 mission. For example, the committee learned that the Spirit and Opportunity rovers are capable of returning far more data than have been obtained thus far. An enhanced communications relay capability would greatly improve data return from future missions. Further, high-resolution imaging afforded by the Mars Reconnaissance Orbiter has proved invaluable in defin- ing a safe landing site for the Phoenix mission. (See Figure 4.2 for an illustration of the Phoenix lander.) Given the critical upcoming landed missions such as Astrobiology Field Laboratory and Mars Sample Return, NASA will have to make an assessment of the likely lifetime and surface coverage of the Mars Reconnaissance Orbiter. The results can then be used to determine whether high-resolution imaging is required for the Mars Science Orbiter. The committee notes that NASA has reoriented the goals of the Mars Science and Telecommunications Orbiter and renamed it the Mars Science Orbiter (MSO). NASA clearly intends for this mission to have a science goal,

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 MARS FIGURE 4.2 The Phoenix Scout mission landing site was selected using high-resolution imagery from the Mars Reconnais- sance Orbiter, demonstrating the tight coupling of spacecraft in NASA’s Mars Exploration Program. Future landers will also require such imagery to select safe landing sites. SOURCE: Jet Propulsion Laboratory. and the committee applauds this decision. However, the committee is concerned about how committed the agency is to funding this mission, considering plans to reorient the Mars program. Finally, as described earlier, a long-deferred goal, a lander network for seismology, meteorology, and other geophysical measurements, might be achieved by incorporating landers on the Mars Science Orbiter. The com- mittee notes that, in general, orbital science and telecommunications orbits are incompatible, and thus mission orbital mechanics design must be carefully defined. The committee observes that the intention of the Mars Exploration Program is clearly to keep scientific objectives uppermost, as reflected in the name change to Mars Science Orbiter. However, without sufficient maintenance of the Deep Space Network, increased data rates from Mars are inconsequential. ADDENDUM: NASA’S NEW MARS DIRECTION The committee’s charter calls for a midterm review of NASA’s progress in relation to the National Research Council’s (NRC’s) decadal survey New Frontiers in the Solar System5 and supporting documents such as Assess- 5National Research Council, New Frontiers in the Solar System: An Integrated Exploration Strategy, The National Academies Press, Wash- ington, D.C., 2003.

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 GRADING NASA’S SOLAR SYSTEM EXPLORATION PROGRAM ment of NASA’s Mars Architecture 2007-2016.6 Since the time of the study initiation, several relevant NRC documents have been published, including An Astrobiology Strategy for the Exploration of Mars,7 The Limits of Organic Life in Planetary Systems,8 and Exploring Organic Environments in the Solar System.9 In addition, as the present report of the committee was in its near-final draft, NASA presented the committee with new information on both the Mars Science Laboratory mission and the agency’s strategic planning for the decade 2010-2020. The set of options under consideration for the decade 2010-2020 potentially represents a dramatic change from what has been recommended in previous NRC documents and thus stimulated this addendum entitled “NASA’s New Mars Direction” to the “Mars” chapter of this report. In addition, the committee perceived very mixed messages about the actual budgetary commitment to a new Mars exploration strategy. The committee urges the community to conduct a more thorough review of the new Mars exploration strategy when the executive branch budget process under way at the time of this writing has been completed and the NASA 2009 budget is publicly available. Mars Science Laboratory Mission The Mars Science Laboratory mission had just had its Critical Design Review (CDR) completed as the present report was being prepared. CDR is the last point at which hardware changes can be made prior to actual spacecraft construction without having significant, and often expensive and time-consuming, effects on the project.10 Thus, the committee was quite surprised to hear that a new requirement had been added by NASA after the CDR: namely, a sample caching mechanism. This mechanism, intended to demonstrate a method of sequestering rock samples for a possible future Mars Sample Return, is now being developed for inclusion on the MSL project. The committee has been informed that the sample caching hardware is only intended to collect a “contingency sample,” not a “primary sample,” and this will not drive the scientific operations or development of the MSL project. The committee notes that this contingency sample will not be a “well-characterized” sample according to current commonly accepted definitions of the term; for example, it will not include samples of high biological interest. The committee sees value in beginning the preparations for Mars Sample Return in such a concrete way, much as the small rover on Mars Pathfinder set the stage for the much more capable rovers Spirit and Opportunity. However, the committee strongly cautions NASA that there are inherent technical, scientific, and programmatic risks in including such a dramatically different requirement after CDR. While NASA personnel provided a plau- sible sketch of the safeguards put in place to prevent this caching requirement from driving or undermining the balance of the mission, the committee believes that very rigorous reviews will have to be implemented to ensure overall MSL mission success. The “Ideal Mars Next Decade Campaign” Throughout most of this report, the committee has generally applauded NASA’s Mars Exploration Program as an impressive and well-managed program achieving substantial scientific results and greatly increasing our knowledge of the red planet. A major exception is the lack of progress toward a Mars Sample Return mission. NRC documents have for many years emphasized the importance of the MSR mission, though often tempering this emphasis with the realization that to justify the significant expense, the sample must be well characterized and 6National Research Council, Assessment of NASA’s Mars Architecture 2007-2016, The National Academies Press, Washington, D.C., 2006. 7National Research Council, An Astrobiology Strategy for the Exploration of Mars, The National Academies Press, Washington, D.C., 2007. 8National Research Council, The Limits of Organic Life in Planetary Systems, The National Academies Press, Washington, D.C., 2007. 9National Research Council, Exploring Organic Environments in the Solar System, The National Academies Press, Washington, D.C., 2007. 10“The CDR demonstrates that the maturity of the program’s design is appropriate to support proceeding [with] full-scale fabrication, assem- bly, integration, and test and that the technical effort is on track to complete the flight and ground system development and mission operations in order to meet overall performance requirements within the identified cost and schedule constraints. Progress against management plans, budget, and schedule, as well as risk assessment, are presented.” NASA Procedural Requirement 7120.5D, March 6, 2007. See http://nodis3. gsfc.nasa.gov/displayDir.cfm?Internal_ID=N_PR_7120_005D_.

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 MARS well selected. In addition, there are a number of technologies unique to MSR that require major advance funding to ensure mission success. Funding for those technologies has been sporadic at best. The committee notes that with the release of the NRC reports on possible forms of life elsewhere in the solar system—The Limits of Organic Life in Planetary Systems, An Astrobiology Strategy for the Exploration of Mars, and Exploring Organic Environments in the Solar System—the NRC has solidly endorsed the “life thread” as a driving goal for the Mars Exploration Program. By continuing the “Follow the water” approach, perhaps augmented by a “Follow the carbon,” “Follow the organics,” or “Find the life” set of scientific objectives, a properly designed Mars Sample Return mission could add an enormous storehouse of scientific information to our knowledge of the universe. The new strategic approach presented in outline form to the committee and described by NASA as the “Ideal Mars Next Decade Campaign” (hereafter referred to as the “Ideal” plan) 11 seems to address many of the concerns contained in the balance of this report. The new strategic approach is founded on the stated goal of “anchoring” a Mars Sample Return mission in the launch year of 2020, with actual samples returned sometime later. This goal requires some further explanation, since the launch year for a single segment of what is likely to be a multiple- launch mission could lead to confusion and misunderstanding. Given below are the committee’s comments on the key elements of the “Ideal” plan. Mars Scout in 2011 The 2011 Mars Scout project was characterized by NASA as being “on track” for a down-selection from two mission concepts to one in January 2008. Both concepts address the long-neglected aeronomy science area, and thus either project will benefit the overall Mars Exploration Program. However, during the committee’s most recent discussions with NASA on future budgets, liens, and threats, it became apparent that funding may not be possible for another Scout Announcement of Opportunity for many years. Given the importance of portfolio bal- ance among flagship, medium, and small missions, the committee finds it inconsistent with recommendations in the decadal survey that the 2011 Scout mission may be the last. Mars Science Orbiter 2013 As noted elsewhere in this report, the architecture of the Mars Exploration Program embraces interdependent missions that provide both scientific context and supporting infrastructure. In the current Mars architecture, the 2013 orbiter provides technology for future missions as well as science that will be solicited by an Announcement of Opportunity in early 2008. Given the likely demise of the Mars Reconnaissance Orbiter spacecraft (currently in orbit around Mars) well before the putative Mars Sample Return launch in 2020, and given the need for landing site selection as well as telecommunications, the committee concludes that there must be some type of science and telecommunications orbiter preceding the MSR mission. The committee is pleased that this critical component is included in the “Ideal” plan, although, based on NASA statements that the 2013 mission could be deleted from the budget, the committee is strongly concerned that this mission could vanish entirely. Mars Sample ReturnGeneral Information NASA told the committee that an MSR mission will be “anchored” in 2020 with a number of associated conditions and objectives: • Extensive international collaboration, perhaps as much as 50 percent; • Alignment with the European Space Agency’s Aurora Program and Exo-Mars in particular; and • Initiation of a first phase of study by the International Mars Exploration Working Group. 11Doug McCuistion, director, Mars Exploration Program, Planetary Science Division, Science Mission Directorate, NASA, “Mars Explora- tion Program Update,” presentation to the committee, Washington, D.C., August 13, 2007.

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6 GRADING NASA’S SOLAR SYSTEM EXPLORATION PROGRAM The committee is very pleased to learn of this new international effort, which corresponds so closely with previous NRC recommendations. Astrobiology Field Laboratory (AFL) 2016 The new “Ideal” plan’s mission queue presented by NASA to the committee now specifies the Astrobiology Field Laboratory as the first step in the MSR effort. AFL would identify, collect, and cache the prime set of samples for return on a subsequent mission. The committee applauds this step in definition of the mission queue, although the committee also wishes to emphasize that appropriate instrumentation must be developed in order for the AFL to realize its astrobiological promise.12 A returned sample that contains organics would add immeasurably to the knowledge of the biological potential of Mars. This mission as now defined is also consistent with the NRC report An Astrobiology Strategy for the Exploration of Mars. Mars Sample Return Missions 2020 and 2022 As has been noted previously, a sample return mission is very costly; it would be expected to consume all of the resources of the Mars Exploration Program over at least three launch opportunities; it will also require stable funding and high reliability. Thus, it was not surprising that NASA’s plan to anchor an MSR mission in 2020 would necessitate skipping the 2018 launch opportunity. The committee was also informed that a 2024 mission might also be deleted to meet the budgetary requirements of the MSR mission. Such economies are clearly neces- sary for such an ambitious project. NASA described the MSR mission as comprising three separate projects and three separate launches. The 2016 Astrobiology Field Laboratory would identify and cache the sample. In 2020, the orbiter that will contain the sample return vehicle and Earth entry system will be launched. Finally, in 2022, the landed system with a sample retrieval rover and the Mars ascent vehicle will be launched. Thus, an actual sample of Mars will not return to Earth until perhaps 2025. The committee was delighted to see a clear sequence of missions that will lead to a Mars sample return in the first half of the 2020-2030 decade. As noted elsewhere in this report, such planning has been suggested by a number of previous NRC reports. However, as also noted in those earlier reports, an MSR mission will not and cannot occur without a significant technology investment, whether by NASA alone or through a shared international effort. In addition, the committee wishes to emphasize that the primary scientific goal should be to obtain a well-selected sample that advances scientific understanding of the biological potential as well as geological history of Mars. Subsequent NRC reviews will undoubtedly evaluate whether the budgetary investment and scientific emphasis continue to advance the MSR mission. Additional Possibilities for Next-Decade Tradeoffs During NASA’s presentation of the well-reasoned and seemingly achievable description of the “Ideal” plan’s mission queue,13 the committee was surprised by the addition of several other options also now being considered by NASA: • Possible cancellation of the 2013 Mars Science Orbiter; • Potential conversion of the 2016 Astrobiology Field Laboratory to an orbiter; • Starting a Mars Sample Return mission in 2018; and • Opening the New Frontiers program to Mars missions. 12The committee notes that the decadal survey recommended slipping the Astrobiology Field Laboratory to 2018, whereas the NRC Mars Architecture report considered it as an option for 2016. The committee believes that keeping the AFL in 2016 and giving the mission a role in the important Mars Sample Return mission is a reasonable decision. 13Doug McCuistion, director, Mars Exploration Program, Planetary Science Division, Science Mission Directorate, NASA, “Mars Explora- tion Program Update,” presentation to the committee, Washington, D.C., August 13, 2007.

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7 MARS The committee finds this set of options, taken together, to represent nothing less than the dismantling of a strategically planned Mars program in return for a promised Mars Sample Return mission well beyond the current budgetary horizon. Some more-specific deductions can be made for each possible tradeoff: • Possible cancellation of the 201 MSO. Without orbital telecommunications support and with the highly probable loss of both the Odyssey and MRO spacecraft by 2011, the carefully constructed Mars scientific and programmatic infrastructure will cease to exist, possibly stranding the 2009 Mars Science Laboratory without high-data-rate capability. In addition, the possible MSO option to include a small number of landers to conduct network science would clearly be eliminated. • Potential conversion of the 2016 AFL to an orbiter. The committee can only conclude that such a move would signal the termination of the astrobiology and the “life thread” of Mars investigations endorsed in numerous NRC and community reports. The “contingency sample” cache by the MSL would presumably then become the prime sample—one selected primarily for its geological interest. Conversion to an orbiter does acknowledge that the subsequent MSR mission would need both site selection and telecommunications support. • Starting MSR in 201. Given the current liens and budgetary requirements of an MSR mission as described by NASA, the committee does not believe that this is a realistic option. • Opening the New Frontiers program to Mars missions. The impact of such a move could be to abandon a strategically planned Mars Exploration Program in favor of a competitive process that is already oversubscribed. The New Frontiers program is currently open to the full range of solar system missions outside of Mars. The success of the Mars Exploration Program has been to combine the strategic exploration of Mars as a system with competition for investigations and instruments meeting those community-based strategic goals. Competition at the small-mission level was met by the creation of the Scout program. The committee notes that the decadal survey placed as much emphasis on the Scout missions as on Mars Sample Return. Any decision to cancel the Scout program completely in favor of MSR would run counter to the decadal survey and will have to be revisited by the Mars community. In summary, the committee finds much to recommend and applaud in the proposed “Ideal Mars Next Decade Campaign.” The sequence of missions, assuming adequate technology investment, addresses nearly all of the concerns expressed elsewhere in this report except for a landed network mission and the demise of the Mars Scout line. The committee is therefore concerned to hear also of a set of options in this “Ideal” plan that would effectively negate nearly everything recommended in many previous NRC studies. Opening the New Frontiers and Discovery lines to Mars missions is no replacement for the current Mars Exploration Program. There is a real risk in this new “Ideal” plan’s architecture that future implementation and budget issues could result in the substitution of an “engineering spectacular” for a scientifically sound Mars Exploration Program. Recommendation: NASA should seek community review to carefully scrutinize the new Mars architecture and its budget implications in order to ensure that the value of the sample returned is worth the cost to the Mars Exploration Program.