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Space Studies Board Search: Jump to Top NewsJump to Science in the Subscribe to our FREE e- Headlines newsletter! NATIONAL ACADEMY OF SCIENCES NATIONAL ACADEMY OF ENGINEERING INSTITUTE OF MEDICINE NATIONAL RESEARCH COUNCIL June 18, 2004 Current Operating Status International Cooperation for Mars Exploration and Sample Return 4 Possible Cooperative Mission Modes and Their Implications Various approaches to establishing cooperative investigation of Mars are possible. For the purposes of this report, the essential aspects of the major approaches, and their implications, can be captured by several general considerations. The USSR has announced intentions for a Mars exploration program, which appears to include in situ surface investigations with robotic rovers, orbiting spacecraft, and sample return. In view of the USSR's announced intentions, the major variables in the set of alternative program modes that the committee has examined are the level of U.S. participation in Mars science and the character of U.S.-USSR cooperation, if any. Three levels of U.S.-USSR cooperation in intensive Mars exploration have been considered by the committee: Independently conducted programs, q Split responsibilities and joint technical operations, and q A highly coordinated exploration program. q Each of the possibilities also assumes that other nations and space agencies would play substantial roles in the planning and execution of Mars exploration within a framework largely defined by the U.S. and USSR programs. The final recommendations are based on an analysis of the implications, for the United States, of each of these possibilities. THE PRESENT STATE OF U.S. MARS INVESTIGATIONS AND PLANNING At the time of this writing, the U.S. program for further, exploration of Mars consists of the Mars Observer mission, scheduled for launch in 1992, as the only specifically planned initiative. The broad survey measurements to be carried out by Mars Observer address a number of important global- and regional-scale questions. The overall understanding of Mars as a planet will be greatly advanced http://www7.nationalacademies.org/ssb/marscoopch4.html (1 of 10) [6/18/2004 10:04:02 AM]
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Space Studies Board by the Mars Observer's mapping of the planet's surface structure and chemistry, investigations of the atmosphere, and measurement of Mars's magnetic field, all of which will set the stage for intensive investigations to follow. The very-high- resolution images that will be obtained of selected small areas will also prove important to the planning of future Mars surface explorations. NASA has undertaken studies of possible future Mars exploration initiatives that might be carried out either by the United States with the participation of international partners or as, part of a truly joint international endeavor with comparable contributions from one or more major partners. As yet, the United States has not announced national plans to undertake any intensive investigations of the martian surface. Experience with the Soviet VEGA project, with the Phobos mission, and with planning for follow-on Mars missions indicates that. the USSR will continue to invite and welcome participation from scientists in Western nations, including the United States. Should the United States fail to assume a major role in the exploration of Mars, there is likely to be some opportunity for U.S. scientists to participate in continuing Mars science through direct affiliations with the Soviet program or, indirectly, through affiliation with scientific teams from the other nations that will participate in a Soviet-led program. However, if the United States forgoes a primary role in Mars exploration, then any cooperation is likely to be restricted to a low level, and U.S. scientists are likely to be involved only in minor or supportive roles as international leadership in this historic scientific endeavor is assumed by the USSR. Primary consideration by the USSR in planning its own projects would likely be directed toward cooperation with European nations and space agencies, and the result would be a highly intensified relationship between those partners. VARIETIES OF U.S.-USSR COOPERATION In this section, the committee summarizes an analysis of the major possible approaches to U.S.-USSR cooperation and, for the purpose of this analysis, notes that (1) the USSR has announced its intentions for Mars exploration in sufficient detail to suggest the scope of that nation's plans and ambitions; (2) USSR leaders have publicly stated a desire for cooperation with the United States in the exploration of Mars; and (3) the USSR is conducting detailed discussions with numerous other nations about the possibilities of participation in Mars exploration. Therefore, the committee assumes that during the next two decades the USSR will conduct a Mars exploration at a level approximating the announced plans. Moreover, on the basis of the public pronouncements, the committee takes as given that the USSR is open to international cooperation in a variety of modes, depending on the desires of potential partners. As has already been noted, the future vigor of U.S. programs and a U.S. posture of international leadership in this area are not assured. However, the remainder of this analysis assumes that the United States will engage in intensive Mars http://www7.nationalacademies.org/ssb/marscoopch4.html (2 of 10) [6/18/2004 10:04:02 AM]
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Space Studies Board investigation beyond the Mars Observer. This analysis also assumes that any cooperation will involve a program extending over a decade, entailing several missions to several diverse sites on Mars, and including both in situ investigations and sample return, as described earlier. The committee considered many possible program scenarios, ranging from strongly linked missions in which mission success would depend on the success of mutual interactions, to more weakly coupled versions, with cooperation implemented in a different way. The analysis of possible cooperative modes includes consideration of several discriminating factors, including (1) impact on the overall science return; (2) the possibility of reduced cost to the United States, within a fixed anticipated overall science return; (3) impact on mission risk; (4) impact on technology development; (5) susceptibility to concerns about technology transfer; (6) contribution to enhancing scientific relationships with the traditional U.S. partner nations; and (7) possible contribution to improving the U.S.-USSR relationship. In addition, several other factors were considered, such as the contribution to building U.S. national prestige. Independently Conducted Programs The lowest level of U.S.-USSR cooperation considered in this report involves a situation in which each nation conducts an independent program of Mars investigation with minimal levels of cooperation or coordination. At this level, it is still assumed that the usual scientific interactions generally characteristic of basic scientific research will continue to occur, including the exchange of data obtained by the missions. This level of cooperation does not preclude the possibility of some operational coordination and interaction to take advantage of circumstances that might arise in the conduct of the separate programs; however, it is assumed that, at this low level of cooperation, such fortuitous possibilities do not play a major role in shaping the plans of either nation. This is the level of cooperation that exists today between the United States and the USSR. Examples include the use of one nation's spacecraft as a communications relay for the other nation. Although `even this relatively low level of interaction requires advanced planning during the spacecraft design stages and for operations, the interfaces that are involved are generally simple and straightforward. With respect to the discriminating factors: Science return. Assuming that a commitment to achieve the scientific q objectives is actually carried out, conducting independent programs may have little fundamental effect on accomplishing the scientific objectives; the United States is fully capable of accomplishing all Mars scientific objectives. However, the ability to maximize scientific return within the constraints of the present technical capabilities of the two sides would be lost if programs were conducted separately. http://www7.nationalacademies.org/ssb/marscoopch4.html (3 of 10) [6/18/2004 10:04:02 AM]
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Space Studies Board Cost. The cost of conducting an independent Mars exploration program q is significant. Assuming fixed scientific objectives, the United States will be forced to provide full resources for carrying out an independent program and for accomplishing the objectives, regardless of the plans and programs of the USSR Risk. The committee identified no inherent impact on mission risk from q conducting an independent program, inasmuch as this is the normal mode of carrying out space science missions. Technology development. The independent approach has the potential q to greatly benefit U.S. technology development. Planning and carrying out an intensive program of Mars exploration and sample return will focus development efforts and implementation in a variety of important technological areas, including scientific instrumentation, propulsion and launch systems, and robotics and artificial intelligence. Many of these developments will have application to other activities on the ground and in space. Technology transfer. An independent program eliminates any additional q risk of technology exposure or transfer that might result specifically from cooperation with the USSR. Relationships with traditional partners. Inasmuch as the United States is q assumed, in this approach, to be conducting a Mars exploration program of its own, then the usual opportunities will be available for cooperation with traditional U.S. partners and allies. This would serve to reinforce a significant area of existing cooperation and would provide many nations with a path to Mars exploration as an alternative to, or in parallel with, participation in a Soviet program. U.S.-USSR relationships. An independently conducted program makes no contribution to developing U.S.-USSR experience in cooperative technical and social endeavors. It could also ignite a space competition similar to the race to the Moon. Split Responsibilities and Joint Technical Operations In this approach the United States and the USSR would undertake a significant level of joint technical operations within the context of one or more missions. The planning and execution of such missions would be conducted collaboratively, and the achievement of major mission objectives would depend on sustaining successful cooperative efforts from the time of initial mission design through to the completion of data analysis. This level of cooperation generally would involve substantial hardware, software, and management interfaces at the level of major spacecraft systems and at institutional and governmental levels. There are potential advantages to this high level of U.S.-USSR cooperation. A commitment by both nations to a fully cooperative venture of the magnitude and duration of a Mars sample return program would have a greater, presumably positive impact on U.S.-Soviet relations than would options involving lesser degrees of interaction and reliance. A high level of cooperation would permit the http://www7.nationalacademies.org/ssb/marscoopch4.html (4 of 10) [6/18/2004 10:04:02 AM]
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Space Studies Board undertaking of ambitious and scientifically outstanding missions, such as the return of Mars samples from a diversity of terrains at less cost to each nation than if the same set of missions were executed unilaterally, although this advantage also accrues to some cooperative options that involve less entanglement at the systems level. Finally, this high degree of cooperation would enable missions that take full advantage of the complementary and mutually supportive capabilities of the two space programs (e.g., the present advantage in .heavy lift capability of Soviet launch vehicles and the advantage of high analytical precision, sophistication, and computational capacity enjoyed by U.S. flight instruments and systems). Against these potential advantages must be balanced several disadvantages. A mission with a high degree of dependence on the cooperative efforts of both the U.S. and Soviet space programs would sit as a potential hostage to political events that might disrupt communication and interaction between the two nations. Missions can be envisioned in which the science could be successfully accomplished by either side even if the bilateral cooperation were truncated for political reasons during the mission planning or operation stages. However, such mission configurations either involve a considerable redundancy of effort, substantially offsetting the cost advantage mentioned above, or admit the possibility of a substantially degraded scientific return if full cooperation is not sustained through the project. A project with a high level of U.S.-USSR cooperation, if it is to yield a savings in cost over unilateral missions of similar scope and if it is to take maximum advantage of the complementary capabilities of the two space programs, involves the assignment of responsibility for major engineering modules to one or the other nation. Whether either nation will agree to relinquish to the other the development of major components of enabling technology is not apparent. There is, in addition, a substantial burden on resources and personnel involved in coordinating and managing the interfaces involved in such intimate cooperation; this would be exacerbated by lack of experience in this kind of activity. This burden would offset the potential savings to an unknown degree and must be weighed carefully in assessing the financial implications of the high degree of cooperation and mutual dependence involved in this approach. In one frequently discussed example of a mission conducted at this level of cooperation, one nation would build a lander and a sample-return vehicle while the other nation would build a roving vehicle for collecting samples and conducting in situ science. The roving vehicle could be carried on the same lander as the sample- return spacecraft or on a separate lander, and one or both nations could launch Mars orbiters to serve as communication links and to conduct global remote- sensing measurements. Obviously, design and logistical considerations would differ depending on the configuration of the one or more landed packages. This type of mission seems attractive, from a cost standpoint, as an individual mission: it would share the cost of an otherwise unilaterally executed rover and sample return mission. Because the rover and the sample-return vehicle—with the latter also assumed to have some limited sample-acquisition capability—each would accomplish important independent scientific objectives, significant science http://www7.nationalacademies.org/ssb/marscoopch4.html (5 of 10) [6/18/2004 10:04:02 AM]
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Space Studies Board would accrue even if one of the two vehicles were to fail. As long as the rover and the sample-return vehicle were launched separately from Earth, the two parts of the mission could also proceed independently of one another should political considerations force a termination of cooperative efforts. However, the science return would be severely diminished if the separate components were not able to complete their combined, fully interactive mission. The lift capabilities of the launch vehicles of the two nations-with the present Soviet capabilities far exceeding those of the United States-and the present U.S. lead in technologies associated with the rover, suggest that the most natural division of responsibilities would be for the United States to develop the rover and for the USSR to construct the sample-return vehicle. Such an assumed configuration would, of course, leave the United States without an independent sample return capability and would relinquish the actual return of martian samples to the USSR (although in such a scenario the returned samples would be jointly controlled by the two nations): This configuration also does not acknowledge the Soviet interest in developing and deploying robotic roving vehicles for use on Mars. If the USSR were to go ahead, in any case, with its plans to develop rovers, the benefit to the USSR of cooperation with the United States might be largely political and scientific, but the financial advantage to the USSR would not be so clear. The longer-term scientific and political benefits of cooperation for the United States would be partly offset by ceding the development of Mars sample-return vehicle technology to the Soviet Union. Altogether, to the extent that technology development is likely to be a major motivation on both sides and to the extent that both launch capability and artificially intelligent robotic technology are seen as desirable by both sides, it is likely that both parties will be reluctant to abdicate the development of either technology. The committee considered the possibility that this approach, taking advantage of the existing complementary strengths of each side, might speed progress toward a launch and result in the earliest initiation of Mars exploration and sample return. The needed technological developments could proceed in parallel. However, the technical, social; and political obstacles associated with inaugurating such a complex cooperative effort in the absence of prior experience could be expected to introduce delays that would be difficult to estimate a priori. Therefore, the committee is not convinced that mission modes involving such very intimate technical interdependence and joint activities at Mars would indeed lead to the most rapid initiation of Mars exploration. With respect to the discriminating factors: Science return. This approach potentially allows the greatest q optimization of overall science return within the constraints of the present technical capabilities of the two sides. With nontechnical restrictions removed, the project could be planned to take advantage of the best capabilities, wherever those might reside. Cost. The cost of conducting missions involving split responsibilities and q joint technical operations on Mars is significant. Assuming fixed scientific http://www7.nationalacademies.org/ssb/marscoopch4.html (6 of 10) [6/18/2004 10:04:02 AM]
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Space Studies Board objectives, then each side would have responsibility for only a part of the overall system, thus opening the possibility for considerable cost savings. However, there are significant costs associated with establishing cooperation of this kind between two nations on opposite sides of the globe, with little prior cooperative experience, and with, poorly established communications. These costs would offset an unknown fraction of the savings that might otherwise be realized. Risk. This approach must be considered to be inherently very risky. The q United States and USSR have no prior experience with the degree of cooperation necessary to carry out a technical project of this complexity or magnitude. There are no previously established modalities of cooperation and relatively few existing lines of communication. Each side has little preexisting working knowledge of the other's technical and management practices or institutions. The demonstrated stability of the relationship is such as to at least raise concerns, at: this time, about relying on the consistency of the relationship over a period of a decade or more into the future. The failure of all or part of the system as a consequence of these risks would, at best, result in a severely degraded scientific return. Technology development. This approach minimizes the effort to develop q the necessary technology by taking advantage of the best capabilities available on each side and by dividing the responsibility so that neither side is responsible for all aspects of a mission. However, it is not clear that either side will wish to yield to the other the most challenging and beneficial of the technology developments. Technology transfer. This mode of cooperation inherently involves the q exposure and transfer of large amounts of technology and technical knowledge. Relationships with traditional partners. In this approach, the opportunities q for participation by traditional U.S. partners and allies would occur within a multilateral framework shaped by agreements between the United States and the Soviet Union. This modality would foster international, multilateral approaches to technical cooperation. US-USSR relationships. This approach has the potential to make a large q and positive contribution to developing cooperative relationships between the United States and the USSR. A Highly Coordinated Exploration Program In this approach, the United States and the USSR would agree to conduct a highly coordinated program of intensive Mars exploration and sample return missions at roughly equal levels of scientific and technical commitment. The two sides would work together at all stages, including the initial planning of scientific objectives, experimental approaches, principles of sample collection, and site selection. However, the two sides would conduct their own self-contained and independently designed missions, with specific interaction at Mars limited to the coordination of networked investigations, when that is beneficial, and to mutual support and backup of communications and data telemetry. The post-mission scientific http://www7.nationalacademies.org/ssb/marscoopch4.html (7 of 10) [6/18/2004 10:04:02 AM]
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Space Studies Board analyses and sample distribution would be conducted with a high degree of cooperation and collaboration. This approach would also permit the United States and the USSR to carry forward, in their individual fashions, other aspects of international cooperation. European scientists and agencies would undoubtedly act to .enhance their scientific participation in the context of opportunities arising in the U.S. and Soviet programs. The approach of conducting a highly coordinated program of separately implemented missions captures elements of each of the other two approaches discussed above. On the one hand, the scientific objectives would be fully met. On the other hand, within fixed scientific objectives, a large cost advantage is apparent. Recognizing that the scientific objectives dictate a sequence of several missions, each side would need to commit to roughly one-half of the needed missions, assuming cooperation in the selection of sites and investigations. The committee considered a number of variations on this approach, which have the effect of increasing the level of joint technical operations while still remaining within the framework of coordinated missions conducted separately. One variant at this level of cooperation could be constructed so as to take advantage of the simultaneous presence of two groups on the martian surface. For example, in the case that both nations mount a complete surface-rover and sample return mission, it would be able to choose complementary landing sites and rover traverse paths so as to optimize the return of a diversity of samples, visit a wide variety of geological features and units, and deploy network instruments over a geographical region that enhances the scientific return from those instruments. While scientific, political, and social benefits of full cooperation would accrue from such a mission configuration, there would be little if any cost penalty, above the cost of conducting separate missions entirely. The failure of one of the missions would result in a decrease of the overall scientific yield but would not precipitate a failure in the coordinated program. The committee also considered mission scenarios in which landing sites would be coordinated and closely spaced so that each rover could conduct a traverse to the sample-return vehicle of the other nation and deliver its collection to that vehicle. Modest scientific gains might include a richer diversity of samples and an enhanced opportunity for some in situ investigations (e.g., rover-to-rover electromagnetic or seismic sounding) and network science (meteorology, seismology, and magnetometry) experiments. A dual surface-rover and sample return mission to landing sites situated within rover traverse range could provide additional robustness if one of the roving or sample return vehicles were to fail mechanically, although providing for this contingency would require substantial advanced planning and hardware coordination. Based on the present state of knowledge of the martian surface, the present limitations on achieving highly accurate targeted landings, the uncertainties associated with operating rover vehicles past unexpected barriers in the martian terrain, and the limited level of enhancement in the scientific return that would occur from such complex operations, the committee concluded that such complex mission scenarios were http://www7.nationalacademies.org/ssb/marscoopch4.html (8 of 10) [6/18/2004 10:04:02 AM]
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Space Studies Board not warranted for early stages of Mars exploration, but might be considered for later missions. The primary distinction between this approach and the approach based on split responsibilities and joint technical operations is that each side would be fully responsible for the overall systems involved in its own missions; there would be no need for intimate technical and management interfaces at the system level that could affect the likelihood of mission success. The committee believes that this would relieve the large extraneous burdens and costs that otherwise could be associated with a cooperative program. However, there would remain the highly desirable possibility of exchanging scientific instrument packages built by one side and included on a vehicle of the other side. The interfaces—both technical and management—associated with such instrument exchanges are relatively simpler than the overall system interfaces and could be designed so as to minimize the likelihood of a major mission failure in the event of problems. Also, in this approach, it is expected that there would be substantial collaboration and exchange of personnel at the science-team level. With respect to the discriminating factors: Science return. This approach allows all of the scientific objectives to be q realized. Cost. The cost-benefit impact of conducting a program of highly q coordinated but separately implemented missions is large. Neither side would be responsible for mounting missions to the entire suite of required sites on Mars. Assuming fixed science objectives, each side would have responsibility for only a part of the overall program. Moreover, because each side would be planning and carrying out its own missions, the overhead costs associated with implementing close technical and management interfaces would be eliminated. Risk. Risk is minimized in a program that has a high level of cooperation. q Because each side would be implementing missions on its own, the interfaces would be minimized. There would be no risk of mission failure due to technical, management, or political failures. Technology development. This approach provides each nation with the q advantages of undertaking full technical development—in the areas of spacecraft launch systems, automation, and scientific instrumentation—needed for Mars exploration and sample return. Technology transfer. This mode of cooperation minimizes the transfer of q technology and technical knowledge. The committee believes that incorporation of modular scientific packages from one nation on a vehicle of the other nation could be accomplished with little concern that unwanted technology transfer would occur. Relationships with traditional parmers. Opportunities for participation by q traditional U.S partners and allies would occur within a context of two separate programs carried out in parallel. It is likely that other nations would seek the best opportunities, among those offered in the U.S. and the USSR programs; for participating in Mars exploration. http://www7.nationalacademies.org/ssb/marscoopch4.html (9 of 10) [6/18/2004 10:04:02 AM]
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