Space Studies Board Annual Report 2002 (2003)

A Report of the Committee on Microgravity Research

Performing experiments in low Earth orbit has been the focus of much of the research funded by NASA’s Physical Sciences Division (PSD) and its predecessors for over 30 years. This microgravity research can be divided into five broad areas, all of which focus primarily on phenomena that are strongly perturbed by gravity: biotechnology, combustion, fluid physics, fundamental physics, and materials science. To these disciplines, the Physical Sciences Division is considering adding research in such emerging areas as biomolecular physics and chemistry, nanotechnology, and research in support of the human exploration and development of space (HEDS). In response to a request from NASA, the Committee on Microgravity Research produced a phase I report, in which it proposed criteria for selecting additional research in these new areas and set forth a mission statement for the PSD.

The present report is the phase II report. In it, the committee identifies more specific topics within the emerging areas on which the PSD can most profitably focus. The committee assesses the current status of PSD’s research programs in combustion, fluid behavior, fundamental physics, and materials science. At NASA’s request the committee did not address work in the biotechnology area, as that area had been the subject of a recent review (NRC, 2000). In assessing the impact of the work, the committee considered the following questions:

• The contribution of important knowledge from microgravity research on the topic to the larger field of which the research is a part;

• The progress made in answering the microgravity research questions posed on each topic;

• The potential for further progress to be made in each area of microgravity research.

Areas of future research in the existing disciplines are recommended, and guidance is given for setting priorities across these areas and within the emerging areas. The scientific impact of the existing disciplines, which

was assessed by addressing questions 1-3, was a particularly important consideration when establishing priorities across the existing microgravity programs.

The microgravity program has evolved considerably since its inception as the “materials processing in space” program of the Skylab era. With the exception of the biotechnology program (NRC, 2000), in the early 1990s there was a major emphasis placed upon outreach to the science communities of which the microgravity disciplines were a part. This took the form of biannual conferences in each of the disciplines prior to the release of a NASA Research Announcement (NRA) and an extensive canvassing of the community with notices of the opportunity to apply for support. The result was much greater visibility for the combustion, fluid behavior, materials science, and fundamental physics programs within the larger fields of which they are part, and an increase in the number of proposals submitted. The impact of this outreach became clear as the committee assessed the quality of the investigators and research in the NASA program. The early 1990s also saw the establishment of the fluid physics and combustion programs in their current forms and then, in the past 5 years, an expansion of the fundamental physics program. More recently, the PSD has begun to expand beyond the traditional microgravity-related disciplines to include research in which gravity may have no role, such as biomolecular physics and nanotechnology.

The recent financial problems of the International Space Station (ISS) have brought a major uncertainty to the future of the microgravity program. Many of the facilities that were destined for the ISS have been delayed, and the crew time available for science has been drastically curtailed. This financial crisis has also affected the ground-based research program. Whether this is a temporary setback or the beginning of the end of the microgravity program remains to be seen. Given the uncertainty, the committee did not consider what ISS resources would or would not be available in formulating its findings and recommendations.

The report contains chapters discussing the impact of the microgravity program on the fields of combustion, fluid physics, fundamental physics, and materials science, along with recommendations for promising avenues of future research in each field. There are also chapters that discuss promising research in the emerging areas and provide guidance on cross-discipline research priorities.

In assessing the impact of the PSD-funded work, the committee employed a number of metrics. These included citation rates for publications of research results, the prominence of the journals in which results were published, the changes to standard textbooks that resulted from research findings, documented influence on industry or NASA applications, and the fraction of principal investigators who are fellows of various societies, who are members of the National Academies of Engineering or Science, or who have received other recognition such as awards in their field.

The research in each of the existing microgravity disciplines (except, as mentioned, biotechnology) was assessed. Below is a partial listing of the research topics that have had an impact on their respective field:

• The fluid physics program has produced a large body of significant research in areas ranging from flows due to surface tension gradients to the dynamics of complex liquids—with important applications to industrial processes such as oil recovery and to NASA flight technologies. The unique access to space provided by NASA has led to the development of ground-based and flight research programs that have enabled growth and advancement of research in such fields as thermocapillary flow, and it has attracted leading investigators to the program, including members of both the National Academy of Sciences and the National Academy of Engineering, as well as numerous fellows of professional societies.

• The combustion program has made important contributions to the fundamental understanding of such combustion behavior as the chemical kinetics of flames and flame length variation, resulting in the correction of both basic theory and college textbooks. The results of studies on smoldering, flame spread, radiative transfer, and soot production have not only led to changes in spacecraft fire safety procedures, but have also advanced knowledge about some of the most important practical problems in combustion on Earth. Some these results are already being incorporated into industry applications such as aircraft combustor design. The NASA program currently supports some of the most distinguished combustion scientists in the world, including members of the National Academy of Engineering and numerous fellows of professional societies.

• The fundamental physics (FP) program has made important contributions to both basic theory and the practice of research in such areas as critical point physics and optical frequency measurement, and its work is

published frequently in the leading scientific journals. Access to the space environment enabled a definitive test of the widely applicable Renormalization Group Theory,¹ while ground research sponsored by the program led to an orders-of-magnitude reduction in the labor, physical infrastructure, and time needed for scientists around the world to perform optical frequency measurements. The program has attracted a high caliber of talent, including six Nobel laureates and over two dozen investigators who are either members of the National Academy of Sciences or fellows of professional societies.

• Research in the NASA materials program has led to major theoretical insights into solidification and crystal growth process and has resulted in both the verification and refutation of classical theories predicting materials solidification behavior and microstructural development. Much of this work also has direct relevance to important commercially processes such as casting and semiconductor production, and research results have been utilized by such diverse industries as metal-cutting tool companies (to improve a production process responsible for hundreds of millions of dollars in annual costs) and jet engine manufacturers. Investigators have received numerous prestigious awards for their work in this program, and a high percentage of them are professional society fellows and members of the National Academy of Engineering and National Academy of Sciences.

Below are the areas of research considered to have a high priority within each microgravity discipline. It should be kept in mind that there are numerous additional areas of promising research in each of the fields that were not given the highest priority at this time and thus were not explicitly recommended. Some of these areas might achieve a higher priority in the future. In addition, the committee expects that in future years the communities will generate new research topics that are equally as promising as those recommended here.

Fluid physics should continue to play a dual role in NASA’s physical science research program. For scientists in general, the program provides access to a unique laboratory that permits the isolation and study of the effects of nongravitational forces on fluid behavior. For NASA, the program provides the basis for acquiring knowledge necessary for the development of the next generation of mission-enabling technologies essential to NASA’s human exploration and development of space. The recommended areas of research are these:

• Multiphase flow and heat-transfer technology. This is a critical technology area for space exploration and a sustained human presence in space (NRC, 2000) and is relevant to numerous terrestrial technologies.

• Self-assembly and crystallization. Such research is expected to advance fundamental knowledge of phase transitions and lead to innovation in terrestrial technologies—for example, the fabrication of novel materials such as photonic crystals.

• Complex fluid rheology. The behavior of complex fluids, such as the particle dynamics and segregation flows of dry granular materials or magnetorheological fluids is important to technologies needed for NASA’s Human Exploration and Development of Space efforts as well as to numerous industrial applications.

• Interfacial processes. Surface-tension-related phenomena are important for a number of mission-related technologies, and the microgravity environment offers experimentalists expanded length scales on which to observe interfacial phenomena compared to Earth.

• Wetting and spreading dynamics. Experimental and theoretical research in these areas is necessary for improved understanding of thin-film dynamics in a variety of applications from coating flows to boiling heat transfer.

• Capillary-driven flows and equilibria. Capillary-driven flows and transport regimes associated with evaporation and condensation are important for both terrestrial and space-based applications.

• Coalescence and aggregation. Research on the effects of gravity (and its absence) on coalescence and aggregation is necessary for HEDS since these processes are important to power and life support systems.

• Cellular biotechnology. Advances in the understanding of transport processes in bioreactors is of importance for HEDS medical applications and could lead to significant advances in the biological sciences and the biotechnology industry by improving the ability to control tissue and cell growth.

• Physiologic flows. Fluids research in connection with biomedical applications (both terrestrial and space-related) will be necessary, for example, to better define paths to effective countermeasures for bone loss in microgravity and to explore the behavior of red blood cells in suspension.

The microgravity combustion research program has been driven by two objectives: (a) a need to understand those physical phenomena thought to be relevant for spacecraft fire safety and (b) a desire to deepen knowledge of fundamental combustion processes on Earth. Both of these objectives are addressed by the following high-priority research:

• Development of computer simulation of fire dynamics on spacecraft. Earth-based fire protection techniques have evolved through thousands of years of fire fighting experience. Since there is no such experience base for space fires, physics-based computer simulations are the only alternative. Such simulations have also proved to be of great value in assessing fire safety and control strategies for fires on Earth.

• Research on ignition, flame spread, and screening techniques for engineering materials in a microgravity environment. The goal of the research is the development of a science-based method for determining the fire performance of materials that are candidates for use in space. The results would also be directly usable in space fire simulation codes described above. The two programs taken together would provide a major advance in the understanding of fires in space and the ability to mitigate their consequences.

• Safety of oxygen systems. One of the critical systems on the ISS and other space, lunar, and planetary habitats is the oxygen generation and handling system. Thus an understanding of the dynamics and extinguishment of fires involving oxygen is necessary.

• Smoldering combustion. Smoldering and transition to flaming combustion in microgravity are significantly different than on Earth and thus require additional studies.

• Soot and radiation. The understanding of basic processes that lead to the formation and emission of small carbon particles in high-temperature combustors remains to be understood, and radiation heat transfer has many critical implications for fire safety.

• Turbulent combustion. Turbulence in general and turbulence in the presence of combustion are exceedingly difficult phenomena to model and understand. Nevertheless, most industrial combustion devices and natural fires involve turbulent combustion, and thus the potential impact of this work is large.

• Chemical kinetics. The chemical kinetics and reaction mechanisms of practical fuels and fuel blends of interest to industry remain unknown.

• Nanomaterial synthesis in flames. Flames provide an inexpensive means of producing nanoparticles for mass use. The work to date has generally been empirical, and opportunities exist for understanding the chemical composition and thermal structure of the flow that is conducive to synthesis of the desired forms of materials.

In fundamental physics, the committee gave high priority to the successful execution of the specific experiments that have already been selected for flight on the ISS. These experiments will test important fundamental principles in physics, and in most cases an experiment’s success would end any further need for space experimentation in that area. These already selected experiments along with new areas that have been given high priority, are as follows:

• Currently selected ISS experiments.

  • Low-temperature experiments. The four experiments planned here, taken along with the results of experiments that have already flown, are expected to provide a full picture of the equilibrium behavior of systems near critical points, including the role of boundaries and the dynamical response to perturbations.

  • Relativity and precision clock experiments. The results of these experiments are expected to substantially improve the precision and stability of atomic clocks.

• Other NASA clock application experiments. By flying other types of clocks simultaneously with the atomic clock experiments, such fundamental ideas as the Einstein weak equivalence principle can be tested.

• Antimatter search and measurements. A positive identification of heavy antimatter would be highly significant for astrophysics and cosmology.

• Elemental composition survey. Measurement of the cosmic ray elemental composition up to and beyond the “knee“ in the cosmic ray spectrum should provide the best clues to the origin of cosmic rays.

Materials science has played a central role in many of the discoveries that have shaped our world, from integrated circuits to low-loss optical fibers and high performance composite materials. These research areas, which also contain many subdiscplines, will continue this tradition of science-driven discoveries of great importance to both the nation and NASA:

• Nucleation within and properties of undercooled liquids. The nucleation process plays a prominent role in setting materials properties. Currently the conditions governing the nucleation of stable and metastable phases are not well understood.

• Dynamics of microstructural development during solidification. The ability to directly link processing conditions to the resulting materials properties is still not at hand because the mechanisms governing the development of microstructure during solidification are not well understood.

• Morphological evolution of multiphase systems. The properties of a material are linked to the size, shape, and spatial distribution of the component phases. Understanding the morphological evolution of these systems will allow prediction of the manner in which the properties of a material evolve.

• Computational materials science. It is now possible to design a material using simulations to obtain a desired set of properties. This will create a new paradigm for designing industrially relevant materials, since the materials will be created with a minimum of costly, time-consuming experiments. This approach can have a significant impact on NASA as it assures that the desired materials properties of interest to NASA will be attained, and done so in a greatly reduced time and with a lower cost.

• Thermophysical data of the liquid state in microgravity. Accurate thermophysical data for the liquid state is required for computational modeling of materials processing.

• Nanomaterials and biomimetic materials. There are many promising avenues for materials research at the nanoscale and at the interface between the biological and materials sciences. These new directions are discussed in the section on emerging areas.

Emerging technologies, particularly at the confluence of the biological, physical and engineering sciences at the nanoscale, offer an ideal opportunity for NASA to leverage knowledge gained from the worldwide investments in these fields in order to address its own technology needs. NASA should stay in a position to capitalize rapidly on anticipated advances in nanotechnology. This includes building and maintaining sufficient in-house expertise and ensuring that PSD reaches out to new communities since many disciplines are involved, including physics, chemistry, biology, materials science, medical science, and engineering. Important technologies for fabricating new materials and devices will originate from novel approaches to molecular assembly, combined with nano- and microfabrication tools and the exploitation of design principles inspired by nature. The following topics were identified by the committee as the most promising areas of future research relevant to NASA needs and PSD capabilities:

• Methods for long-term stabilization of proteins in vitro. Long-term preservation of protein function is essential to the utilization of proteins in space in sensors, for diagnostics, and in bioreactors on extended flight missions.

• Cellular responses to gravity-mediated tissue stresses. Developing a mechanistic understanding of how applied loads and stresses affect cellular processes and the underlying molecular processes will lead to a better understanding of the impact of low-gravity conditions on human health.

• Technologies to produce nanoengineered hybrid materials with multiple functions. Investments in nanoengineered materials consisting of diverse molecular species or phases, or hybrid materials, could provide NASA with new materials that can sense, respond, self-repair, and/or communicate with the user.

• Integrated nanodevices. Emerging technologies for engineering micro and nano-devices able to sense, process acquired data, and take action based on sensory inputs could contribute significantly to achieving NASA’s goals.

• Power generation and energy conversion. Nanotechnology promises to increase the efficiency of energy conversion, decrease weight, and increase the overall energy density for energy storage.

• Knowledge base for stabilizing cell function in vitro. Efforts to stabilize cells may represent an effective strategy for producing needed cell types to meet emergencies on demand while eliminating the need to keep an extensive inventory of cell types available in space.

In order to assess and compare research across the microgravity disciplines, the committee critically examined the potential impact of the research on the scientific field of which it is part, on NASA’s technology needs, and on industry or other terrestrial applications. The committee’s evaluation of research in each of these categories is expected to assist NASA program planners by providing the insight into likely risks and potential rewards of the research necessary to create a vibrant microgravity research program that has an impact in all of these areas.

Because of the brief history and rapid development of the fields of research in the emerging areas, it was not possible to evaluate research in those areas using the same criteria applied to the research in combustion science, fluid physics, fundamental physics, and materials science. While the likelihood that PSD-funded research in emerging areas will have significant impacts on NASA cannot be evaluated at this time, the magnitude of the impact of successful research is potentially very high. Therefore the committee ranked the priority of research topics in the emerging areas only relative to each other, and suggests that PSD utilize the prioritization to help allocate funds that have been set aside for these emerging areas.

When comparing research across disciplines, the committee considered only those areas already identified above as having a high priority for one of the disciplines. To evaluate the recommended research areas, the committee separately judged the likelihood that the research would have a significant impact in (1) the scientific field of which it is part, (2) industry or terrestrial applications, and (3) NASA technology needs. Within each of these categories the committee specifically looked at both the magnitude of the potential impact that the research would have on that category, and the likelihood that the research would be successful in achieving that impact. The impact and probability of success were assessed independently of each other since it was possible for areas with a potential for high impact to have a low probability of success and vice versa. The results of the committee’s assessment are plotted in Figures ES.1, ES.2, and ES.3. Note that the setting of actual research priorities must depend on NASA’s programmatic goals and that those goals determine both the desired end result, such as scientific discovery, and the level of acceptable risk. The purpose of these plots then is to provide NASA with the tools with which to rationally select the best research, regardless of which combination of scientific discovery (Figure ES.1), terrestrial applications (Figure ES.2), or NASA technology needs (Figure ES.3) that NASA chooses to emphasize or what trade-offs between research risk and reward it is willing to accept.

All of the areas recommended below satisfy the criteria identified in the phase I report for choosing research in the emerging areas. The development of methods for the long-term stabilization of proteins in vitro and research on cellular responses to gravity-mediated tissue stresses are of higher priority than the others, because these areas are not typically supported by other agencies. The research on exploiting nanotechnology for power generation and energy conversion is also ranked “most important“ because of the great importance of power generation and energy conversion in NASA’s spaceflight program, and the major

impact these technologies may have on this program. The remaining areas ranked important are heavily supported by agencies such as DARPA, DOE, NSF, and DOD as well as by other divisions within NASA. Thus PSD should partner with these agencies or other divisions within NASA to pursue such research. In the past, PSD has successfully partnered with other agencies, such as the National Cancer Institute. The recommended topics are given below. Note that these are not rank-ordered within each category.

• Develop methods for the long-term stabilization of proteins in vitro.

• Understand cellular responses to gravity-mediated tissue stresses.

• Exploit nanotechnology for power generation and energy conversion.

• Develop enabling technologies to produce nanoengineered hybrid materials with multiple functions.

• Develop integrated nanodevices.

• Stabilization of cellular function in vitro.

When considering the question of the overall balance within PSD between microgravity research and research in the emerging areas, the committee looked at several factors. These included the degree of support received by topics in emerging areas from other government agencies and other divisions within NASA, the considerable potential of the microgravity research disciplines to yield important new results, the potentially high impact of successful research in emerging areas, and the ability of the PSD to provide unique resources or knowledge. These and other factors argued for a balanced PSD program of research that retains the unique potential for studying the effects of gravity on phenomena in combustion, fluid physics, materials, fundamental physics, and biotechnology topics such as tissue culturing. The committee concluded that the relative proportion of the physical sciences program devoted to the emerging areas should remain relatively modest, perhaps 15 percent of the program, until such time as a clear justification arises for increasing its size. This fraction of the program should allow NASA to have an impact on a limited number of highly focused topics within the broad emerging areas while leveraging the research of other agencies. It would also permit the majority of the research in the microgravity areas to continue to produce the high-impact results described in the discipline chapters.

The committee has commented numerous times in past studies on the role that rigorous peer review has had in greatly improving the quality of the research funded by the Physical Sciences Division, and strongly recommended its continued use in future funding selections. As the program moves into new areas of research it is worth emphasizing again that any research proposal submitted to the program—no matter how relevant to an area considered highly desirable for inclusion in the program—should be funded only if it has undergone a rigorous peer review and has received both high marks for scientific merit and a high ranking compared with competing proposals.

National Research Council. 2000. Future Biotechnology Research on the International Space Station. Washington, D.C.: National Academy Press.

National Research Council. 2000. Microgravity Research in Support of Technologies for the Human Exploration and Development of Space and Planetary Bodies. Washington, D.C.: National Academy Press.

A Report of the Task Group on the Availability and Usefulness of NASA’s Space Mission Data

The National Aeronautics and Space Administration (NASA) has become a knowledge agency. Long after the Mars Surveyor has gone silent, Hubble has met the same fate as Mir, and the Moderate Resolution Imaging Spectroradiometer has produced its final set of images, what will endure are the volumes of valuable data that these instruments and many others have collected over their lifetimes. NASA data sets are revolutionizing the fields of astrophysics, solar system exploration, space plasma physics, and Earth science. As this impressive collection of observations has grown, NASA’s mission has also expanded—evolving from an emphasis on mission planning and execution to include the collection, preservation, and dissemination of Earth and space data.

Spacecraft that will be launched during the next decade will increase the data volume returned by NASA missions a hundredfold. These rich data sets will open new eras in precision cosmology and in understanding of the complex linkages in the forces that shape the Earth’s environment. Addressing the increasingly complex questions that can now be asked—and answered—through the use of NASA data will require the capability to compare and combine observations of different types and to discover patterns and relationships through sophisticated querying tools. The user community will need still-to-be-developed tools and methodologies for accessing, analyzing, and mining data; recognizing patterns; and performing cross-correlations that are scalable to a billion or more objects. Developing the necessary tools will present new challenges to space scientists, to the information-technology community, and to NASA. Investments in scientific analysis and in packaging data in formats useful to other potential users, including educators, those in industry, state and local government officials, and policy makers, will be needed in order to exploit the full potential of existing data set. The end product of each mission—knowledge— must be the key factor in determining mission design and budget allocations.

The Task Group on the Usefulness and Availability of NASA’s Space Mission Data was charged by NASA’s associate administrators for Earth science and space science to evaluate the availability, accessibility, and usefulness of data from Earth and space science missions, and to assess whether the balance between attention to mission planning and implementation versus data analysis and utilization is appropriate. Based on input from various sources—recent National Research Council (NRC) and other advisory committee reports; interviews with the chairs of relevant NASA advisory committees and discipline committees within the NRC; information gathered from NASA headquarters; and the task group’s survey of the archives, data centers, and data services and use of their Web sites—the task group’s answers to the charge (see Appendix A) are summarized below:

Charge 1. How available and accessible are data from science missions (after expiration of processing and proprietary analysis periods, if any) from the point of view of both scientists in the larger U.S. research community, as well as U.S. education, public outreach and policy specialists, and private industry? What, if anything, should be changed to improve accessibility?

As few as 10 years ago, NASA’s data collections were accessible mainly to researchers involved with specific missions. With the advent of a NASA network of active archives, data centers, and data services, most newer data sets have become widely available, especially to researchers. Enhancements in bandwidth and planned increases in the number of online data sets available through publicly accessible data facilities will improve the accessibility of NASA’s Earth and space science data still further over the next decade. However, much of the older data (e.g., in the fields of solar and space physics and planetary science) is still in the hands of principal investigators (PIs) or is not

available in formats that users need. Other data or information products (e.g., education and nonscientific applications products) are available on project Web sites but may require extensive searching to find, and their long-term availability is not assured. Further improvements in cataloging and documentation will be required to help users find data.

Charge 2. How useful are current data collections and archives from NASA’s science missions as resources in support of high priority scientific studies in each Enterprise [i.e., NASA’s Earth Science Enterprise and Space Science Enterprise]? How well are areas such as data preservation, documentation, validation, and quality control being addressed? Are there significant obstacles to appropriately broad scientific use of the data? Are there impediments to distribution of derived data sets? Are there any changes in data handling and data dissemination that would improve usefulness?

The use of archival data has contributed to a number of scientific advances in the Earth and space sciences (e.g., confirmation of the Antarctic ozone hole and the accelerating expansion of the universe). The large and growing number of users—coupled with the positive results of user surveys, external reviews, and the task group’s own experience with the data facilities—attests to the usefulness of the data in a wide variety of investigations.

Many data sets will grow in value as the time period covered by the measurements lengthens. However, getting the most out of existing data sets will require the development of software tools for handling the data (e.g., for changing formats, subsetting large data sets, and querying and visualizing data sets) and improvements in documentation, user interfaces, and technical and scientific support. These improvements will be even more important for dealing with the projected growth in the volume of data (one to two orders of magnitude over the next 5 years) and the increasing need to integrate disparate data sets for both research and applications purposes. Maintaining accessibility and compatibility with changing standards for storage media, software tools, and so forth in the long term will present substantial challenges in terms of both cost and management. Although issues of validation and quality control of individual data sets were not directly addressed in this study, the task group’s generally positive findings about data usefulness suggest that these issues do not now pose either major or widespread obstacles to data use. However, they will require heightened attention in the future as demands on the active archives increase.

NASA data have the potential to benefit society in many ways, but in order to exploit this potential it is necessary to provide support for the translation of scientific data into data products that are tailored for specific applications. These data products must be easily accessed and interpreted by people who are experts in the fields to which the data are being applied, but who will very likely have limited or no training in fields for which the data were originally collected. The work of Earth Science Information Partners, Regional Earth Science Application Centers, Infomarts, and similar applications programs is an important step in increasing the usefulness of NASA data. However, meeting the needs of the broader community would require a very substantial additional investment of resources, and such investments should be preceded by an assessment of the market for NASA information and a prioritization of investments according to cost-effectiveness and likely impact.

Charge 3. Keeping in mind that NASA receives appropriated funds for both mission development as well as analysis of data from earlier or currently operating missions, is the balance between attention to mission planning and implementation versus data utilization appropriate in terms of achieving the objective of the Enterprises? Should the fraction of a mission’s life-cycle cost devoted to data analysis, processing, storage and accessibility be changed?

Declines in funding for analysis of space science data in the 1990s have been reversed in recent years, although funding remains insufficient for analyzing data during extended missions or after missions have been completed. The major exception to this generalization is for long-lived astrophysics missions, where funding for data analysis, including analysis of archival data, is made available for a decade or more after launch. Despite changes in the way budgets are reported, the fragmented budget structure of both enterprises makes it difficult to quantify the adequacy or inadequacy of funding.

Rigid guidelines for the balance between support for mission planning and implementation on the one hand and data utilization on the other are inappropriate. However, in view of the expected growth and diversification in the

data products from future missions, NASA should address more explicitly the issues of balance in its planning and management of missions and programs and it should do so utilizing mechanisms that involve the user communities. Trade-offs within the life-cycle budget should be made in such a way as to optimize the overall scientific return, even if that means reducing mission capabilities for data acquisition.

Specific recommendations related to the task group’s charge are presented in the sections that follow.

Concerns about the management of NASA data sets have been identified in several earlier NRC and General Accounting Office reports. The task group concludes that the management of science data and information has become a function of sufficient scope and importance that its successful execution requires leadership with the expertise to carry out these tasks:

• Provide strategic planning, oversight, and advice concerning the collection, processing, archiving, and dissemination of data and information collected by NASA’s space missions;

• Be the advocate for the appropriate balance of investment in data analysis;

• Ensure the preservation and accessibility of valuable space mission data and information;

• Require a data management plan for each mission and monitor its implementation;

• Provide oversight for the design and implementation of software, hardware, and database systems for processing and storing NASA’s massive data sets;

• Develop a long-term software plan for NASA’s Earth Science and Space Science Enterprises;

• Require interenterprise communication and sharing of successful methods and systems for data management;

• Work out the memorandums of understanding governing access to data from those missions that are carried out cooperatively with other countries; and

• Determine how information generated by the space programs of other countries can be accessed and effectively used by U.S. scientists and institutions.

The person(s) charged with the tasks listed above should also create and draw on the experience of an advisory panel composed of instrument scientists, computer scientists, chief information officers (CIOs) from major corporations and government organizations, and an electronic-records expert from the National Archives and Records Administration. Analogous to the position of CIO in a major corporation, the NASA person(s) in charge of the information-management function should have budgetary responsibility for the collection, analysis, and long-term maintenance of all Earth and space science data sets. This responsibility could consist of either holding the budget for designing the data collection, analysis, dissemination, and archiving function for each mission or having the right of refusal for projects and programs that do not handle it adequately, or both. In parallel with the title of CIO in industry, this person might appropriately be called the chief science information officer(s) (CSIO; this title distinguishes the functions addressed here from those of the chief information officer at NASA, who is primarily responsible for NASA business systems and security). The CSIO(s) would have responsibility for the data acquisition and utilization component of every mission and would advocate investment in data management at a level that optimizes the overall scientific return of a mission when trade-offs between hardware and data must be made.

Some of the responsibilities outlined above relate to cross-NASA issues, while others are more specific to individual program offices. Accordingly, they could be carried out either by a single individual or by individuals assigned to each of the enterprises. However, whatever administrative structure is selected, it should be one that supports cross-enterprise communication and cooperation and provides the support and authority needed to ensure that the CSIO is effective in carrying out the functions identified here.

The recommendation to consolidate the information-management function does not imply that NASA should centralize all data aspects of all missions. The task group believes that a combination of distributed and centralized activities is necessary. For example, analysis and production of data products should probably continue to be performed in a distributed manner by scientists, while long-term maintenance of data is probably best handled centrally. The NASA CSIO(s) would be responsible for overseeing the development of the overall architecture of the data and information “production line,“ while leaving much of the actual design, implementation, and operation to the scientists and engineers directly responsible for each mission.

The scientific productivity of a space mission depends as much on the readiness of software and data flow pipelines as on the readiness of the sensor and spacecraft hardware. Therefore, NASA science missions should be viewed as integrated systems of hardware and software. The trade-offs among capabilities that are inevitable in missions and programs with fixed budgets must include not only the funding for new missions, the development of new capabilities, and the fabrication of spacecraft instrumentation, but also the funding for software development for mission operations, data distribution, and data analysis. In cases where hardware cost overruns occur, maintaining an adequate investment in software and scientific analysis may well require reducing the capabilities of the mission itself. Ground and flight systems should be designed in conjunction in order to achieve cost-effective data acquisition and analysis.

Recent program solicitations from both the Earth Science and Space Science Enterprises require the PIs to prepare budgets for the total mission cycle cost—from mission definition to data processing, publication, and archiving. The task group encourages the continuation of this practice.

The prime mission phase includes the development, launch, data collection, and analysis for a fixed period of time that is estimated to be sufficient to answer the minimum set of scientific questions that must be addressed in order for the mission to be judged a success. However, for many missions and many scientific problems, the value of data extends well beyond the termination of the prime mission phase. Missions are extended, calibrations are improved, novel uses of the data are made that were neither foreseen nor planned by the original mission investigation team, and many significant discoveries occur only after a variety of heterogeneous data sets are integrated and studied. The peak publication rate for a mission often occurs 4 to 5 years after launch. All of these factors argue for continuation of support for scientific analysis after the prime mission phase is completed. Mechanisms (e.g., proposal pressure and advisory committees) exist for setting priorities within a discipline. However, NASA, in consultation with the scientific community, will have to develop mechanisms for addressing issues of balance across disciplines or between new missions, extended missions, and postmission data analysis within or between programs. Whatever mechanism it chooses should be carried out on a regular and systematic basis.

NASA currently provides a data center—the National Space Science Data Center (NSSDC)—for long-term maintenance of space science data. However, the NSSDC faces tremendous challenges in serving current users as well as future generations of scientists. Many scientifically valuable data sets are not archived in the center, and those that are may not be sufficiently well documented or formatted to be readily accessible. Declining budgets and rapidly growing volumes of holdings will only exacerbate these problems. A permanent storage facility is not even available for most of NASA’s Earth science data. Instead, these data are to be transferred to the U.S. Geological Survey and the National Oceanic and Atmospheric Administration 15 years after collection. Even if adequate

resources can be found, transferring petabytes of data from those familiar with them to organizations with little knowledge of the data entails a risk. Because NASA data sets are a national resource and because the value of many of them increases in direct proportion to the time interval covered by them, it is important to preserve the data indefinitely. The care of the data must be accomplished so as to maximize their knowledge-enhancement possibilities, scientific impact, and discovery potential.

Many of the important scientific problems of the 21st century in both space and Earth science will require the ability to explore and integrate data obtained from different spacecraft and different instruments. Rather than creating a single information system to meet the evolving needs of a wide range of users, it is now possible, and may even prove to be more cost-effective, to create a federation of distributed databases with universal standards for archiving and to provide common and easily used visualization tools. Federations capitalize on bottom-up decision making and local, custom solutions to specific user needs. A prototype federation of Earth Science Information Partners, which has been operating for 3 years, has demonstrated the ability of different NASA-funded organizations to cooperate, provide system operability at the catalog level, and produce specialized data products. The astrophysics community has developed a plan called the National Virtual Observatory (NVO), which would provide common access tools for their multiwavelength databases; development of the overall architecture and establishing of metadata standards have been funded at a level of $10 million over the next 5 years by the National Science Foundation (NSF). These and other grass-roots efforts to establish multimission data sets and data products in support of interdisciplinary or cross-cutting approaches should be nurtured, although they may not be the best solution in every case. A challenge for the future will be to develop methods for making complex queries of these federated databases.

• The National Virtual Observatory, an astrophysics project funded recently by the National Science Foundation (NSF), will develop the architecture, standards, and so forth for creating a distributed system of data centers that can be cross-accessed and queried in a transparent manner by users. NASA should coordinate with the NSF-funded work on the NVO, which is predicated on seamless joint access to ground- and space-based data, to ensure that space data are compliant with NVO standards.

• NASA should encourage close communications among the groups operating or developing federated systems in order to transfer best practices among its various scientific programs.

• The successful implementation of methods for making complex queries of multiple databases is likely to be technically challenging and costly. The level of appropriate investment by NASA in federated data systems should be evaluated at regular intervals and should be based on (1) the importance of the scientific questions that can be addressed through the simultaneous mining of multiple databases, (2) demonstrated scientific return from past investments, and (3) the readiness of computational and communications technology to support data mining.

The Earth science community has a particular need to generate and access data within a unified framework that integrates data sets and data centers in a seamless way. The Earth Observing System (EOS) Data and Information System (EOSDIS) Core System (ECS) software was intended to provide “one-stop shopping“ access to multidisciplinary data in a timely manner. This goal was not, and probably could not have been, achieved with the technology

available at the time the ECS was designed. A restructured ECS with fewer capabilities will be used for a subset of EOS missions, and data processing and distribution for the remainder will be handled by active archives or PI facilities.

NASA recognizes the problems associated with EOSDIS and is developing a strategy for the evolution of the network of data systems and service providers that support the Earth Science Enterprise. The next-generation system is called SEEDS (Strategic Evolution of ESE Data Systems). SEEDS is intended to support all phases of the data management life cycle: (1) acquisition of sensor, ancillary, and ground validation products necessary for processing; (2) processing of data; (3) generation of value-added products via subsetting, format translation, and data mining; (4) archiving and distribution of products; and (5) search, visualization, subsetting, translation, and order services to assist users in identifying, selecting, and acquiring products of interest. Study teams drawn from the user community will be engaged to identify options, define scope, and establish schedule requirements. SEEDS is intended to be managed and implemented as an open and distributed information system architecture under a unifying framework of standards, core interfaces, and levels of service. SEEDS is a work in progress; details about the implementation plan were not available at the time this task group concluded the current report.

NASA currently regards scientists as the end users of data from its missions. While scientists are a major user segment, there are many others, including project and program managers, engineers, educators, the general public, and decision makers. These users need information, rather than data, in order to design and operate missions and to make policy decisions.

The task group has identified several elements that appear to be common to those overall data management systems that best meet the requirements of the science communities that they serve. These elements are listed below and should be included in planning for future missions and facilities:

• Archives and data centers should have (1) scientists on staff with a strong background in the scientific discipline being supported and (2) scientific working groups to help set priorities for acquiring, managing, and discarding data.

• Prelaunch funding should be provided for software development to ensure the timely development of pipelines for processing newly acquired data.

• Multiyear funding should be provided for research, including research using archived data, on the basis of the quality of the proposals received. A recent senior review (the highest level of peer review within the Space Science Enterprise) of extended planetary missions, for example, noted the success of the archival research programs maintained in astrophysics and suggested that these programs might profitably be emulated by the Planetary Data System.

• Guest investigator programs should be established to allow the community to conduct research not planned by the initial project teams.

• Early and open access to data should be provided to permit follow-on proposals to take advantage of new discoveries.

• A mechanism should be established (such as the senior reviews in space science) for making trade-offs among operations of long-lived missions and operations of active archives and data centers in a way that reflects the scientific merit of the range of possible investments.

The importance of managing data and information from NASA’s space missions will only continue to grow in the coming years. Maintaining the increasing volumes of data in forms that are readily accessible and that meet the needs of very diverse user communities presents intellectual challenges that are at least the equal of the challenges of building and launching hardware into space. NASA is well positioned to become a leader in developing the techniques and tools for querying and mining large nonproprietary data sets. However, doing so will require a new emphasis on software management; rigorous review of the balance between investments in software and hardware to optimize the science return from both individual missions and suites of missions; and development of new techniques for exploring and intercomparing data contained in a distributed system of active archives, data centers, and data services located both in the United States and abroad.

A Report of the Task Group on Research on the International Space Station

Construction of the International Space Station (ISS), under development since the late 1980s, began with the launch of its first element in November 1998 and is ongoing. In the spring of 2001, NASA announced that it would make major changes in the final configuration of the ISS in order to address serious construction cost overruns. The new ISS configuration is referred to by NASA as “Core Complete”; the earlier configuration was based on NASA’s Rev. F design documentation. Some decisions regarding the new configuration are yet to be finalized, but the changes from Rev. F currently include the deletion of a crew return vehicle, which will force a reduction in the number of ISS crew from six or seven to three; the deletion of a number of the major science facilities planned for the ISS; and a reduction in the number of annual shuttle flights to the ISS. Serious concerns have arisen within the science community and elsewhere that these changes would jeopardize the ability of the ISS to support the world-class science that has often been cited as its primary purpose. This report examines the factors, including ISS design changes, that limit the ability of the science community to utilize the ISS for research and makes recommendations for maximizing the ISS’s research potential.

The task group reviewed individually most of the principal areas of science that were intended to be supported on the ISS and considered the impact that the design changes would have on each. The level and type of impact resulting from the design changes in the ISS vary considerably from discipline to discipline. The physical sciences received the majority of the cuts made in facilities and equipment for experiments. Two of the three materials science research racks planned for the ISS were canceled, along with all but two of the experiment modules for the remaining materials facility. More than half of the planned materials investigations on the ISS were deselected, and the scope of work for those that remain has been reduced dramatically. One of the two facilities supporting fluids research (it was also intended to support combustion research) was canceled, along with a number of experiment modules. About 28 percent of the planned fluid physics experiments have been canceled so far, with the remaining experiments now expected to fly in 2005-2008 if funds become available for the development of the experiment modules. The only remaining facility for combustion research was canceled and then reinstated, but its future remains uncertain. The stowage space for combustion research was reduced by half and its allocation of crew time by 70 percent. The result is that each set of combustion experiments has been replanned and will be constrained to fewer tests over a smaller range of conditions, thus reducing their scientific value.

Fewer cuts were made in the equipment needed for research in bioastronautics, but the lengthy delay in availability of the centrifuge and the delay or cancellation of animal habitats will prevent research on the animal models needed to study radiation effects and bone and muscle loss until those facilities can be built and installed. Cell science and biotechnology research, which includes research on bone and muscle cells, will now be limited to two EXPRESS racks instead of six. The reduction in crew size will reduce by at least half the number of subjects from which critical data on human physiology and behavior can be collected, thus doubling the number of years needed to obtain a statistically significant data set. In areas such as plant biology and radiation studies, considerable specialized training is needed to perform experiments, and this training is far less likely to occur with a smaller crew. In fundamental biology many experiments are labor-intensive, and the reduction in crew time is expected to critically compromise experiments in this area.

While some research areas are more severely affected than others by the changes, clearly NASA’s revision of the ISS to the Core Complete configuration has drastically reduced the overall ability of the ISS to support science.

The reduction, singly or in combination, of upmass capability, research facilities and equipment, and available crew time for science activities severely limits or forecloses the scientific community’s ability to maximize the research potential of the ISS. Moreover, the absence of any overarching, well-articulated goal on which to base scientific priorities that would unify or guide the downsizing process has further exacerbated the already significantly diminished capability of the ISS. The impact on the various scientific disciplines of revising the ISS to the Core Complete configuration varies but in all cases is substantial. Although NASA’s stated goal for its ISS program is to create a world-class laboratory, it is the opinion of the task group that the actions taken with regard to crew time, equipment, facilities, and logistics make this unlikely. Specifically, the task group found the following to be the most significant factors limiting the ability of the science community to maximize the research potential of the ISS:

• Interdisciplinary priorities not in place. Decisions to cancel or greatly delay experimental facilities and equipment vital to specific scientific disciplines were made in the absence of cross-disciplinary priorities to guide the selection process. In many cases these decisions were made based primarily on what equipment had not yet been built, without any apparent weighting of the impact on overall scientific objectives.

• Crew time. The most widespread and significant impact of ISS design revisions on the achievement of scientific objectives stems from the more than 85 percent reduction in crew time available for scientific activities.¹ This limitation has an impact on every discipline examined, ranging from a potential total elimination of the ability to achieve even a modicum of meaningful work on the ISS in the areas of radiation biology, systems physiology, crew behavior and performance, and fundamental biology, to lesser impacts on disciplines such as plant science, materials science, fundamental physics, combustion science, and fluid physics. Even these potentially less seriously affected fields will probably sustain significant negative impacts when they are forced to compete with the remaining scientific complement for the minimal time available.

• International partner participation. ISS partners will also experience major reductions in their ability to perform science on the ISS as a result of the Core Complete design. As a result, serious questions have been raised about whether international partners will continue to support ISS development at originally planned levels. Such reductions could seriously reduce the remaining science capabilities of the ISS since the international partners are responsible for elements critical to many U.S. investigators. Loss of the Japanese experiment module exposed facility, for example, would all but eliminate research in fundamental physics.

• Science facilities and equipment. Many U.S. experiment racks have been eliminated or delayed indefinitely in the redesign of the ISS. In addition, the modules containing the functional equipment that goes into the remaining racks have also been reduced significantly in number, worsening an already dramatically reduced capability. The scientific disciplines affected most severely by these reductions are materials science, fluid physics, fundamental biology, and muscle and bone physiology.

• Shuttle upmass capacity. The upmass and stowage volumes for many of the experiments are expected to be severely curtailed as a result of the reduction in shuttle flights and facility changes in Core Complete, and the quantity of scientific work is expected to be reduced accordingly. In fact, the constraints of meeting ISS operational needs with only four shuttle flights per year is expected to leave very little shuttle volume for ferrying supplies and equipment to experiments on orbit or for returning samples to the ground.

• Research community readiness. The factors cited above, when combined with the poor track record of NASA and the ISS in meeting schedule, budget, and scientific performance targets, further detract from the ability of the ISS to garner the support of the scientific community. The uncertainty and instability in the ISS program are disincentives to participation by both established and next-generation scientists, whose careers can be seriously damaged by the failure of the ISS program to provide the promised scientific opportunities.

In considering ways in which the research potential of the ISS could be maximized, the task group looked at two possibilities: options based on the restoration of certain critical capabilities to the ISS, and options based on the

current Core Complete configuration. Described below are the steps that would have the greatest impact on the overall research potential of the ISS. Suggestions for additional steps that would maximize research in specific disciplines are made in the discipline chapters of the report.

Currently a tension seems to exist between using ISS research resources (such as crew time) to enable the human exploration of space, and using those resources to perform research that has intrinsic scientific importance. These two goals are not mutually exclusive, but without cross-disciplinary prioritization both within and across the research supporting the two goals, intelligent use of the scarce and costly resources of the ISS is impossible. As this report is being written, no cross-disciplinary prioritization plan exists.² This lack of cross-disciplinary prioritization exacerbates the uncertainty that is undermining the confidence of the scientific community and its readiness to support the program.

In the life sciences, the human physiology research and operational medicine programs both involve activities that influence or perturb the same physiologic parameters in astronauts. Currently, these activities are not coordinated systematically, which can result in inadvertent corruption of scientific data as well as inefficient expenditure of resources.

As already noted, the time available for science activities on the ISS is wholly inadequate and is the single biggest factor that is limiting achieving science objectives. Of the approximately 20 hours of crew time per week currently identified by NASA for science-related activities, the United States will be allotted only 7.5 hours. This is not sufficient to take advantage of even the reduced scientific capabilities of the Core Complete ISS. According to NASA, the factor currently limiting the crew size to three is the inability, in the event of an on-board emergency, to deorbit more than three crew members due to the limited capacity of the Soyuz and the indefinite postponement of the planned Crew Return Vehicle.

The transition of the ISS from Rev. F to Core Complete has severely limited the facilities available to accomplish U.S.-based scientific research. Increased collaboration with international partners to share facilities and crew time could enable research that the U.S. science community cannot accomplish alone.

The elimination or postponement of ISS experiment racks, modules, and equipment has greatly reduced the potential scientific yield of the ISS. Once a science prioritization on a cross-disciplinary basis is accomplished and the number of crew members available for scientific activities is finalized, the decisions about which experimental modules and experimental equipment are needed can be addressed intelligently. A rational plan that is consistent with stated scientific priorities is critical to assuring the scientific community that the ISS has a scientific future.

The development cost to the United States of the ISS as currently planned is approximately $26 billion. The additional cost to increase the crew number to seven has been estimated at approximately $5 billion. This 20 percent increase in development cost would yield a 900 percent (4.5 versus 0.5 crew available for scientific activities) increase in the crew time available for research. If the primary objective of the ISS is indeed to be a world-class laboratory in space, then the cost-benefit of taking this course of action is obvious. Not to do so would be akin to building a million-dollar home but stopping short of running electrical and water services to it. Without plans and decisions based on cross-disciplinary priorities that are clearly articulated and supported by corresponding allocations of resources, the ISS can never achieve the status of a world-class research laboratory.

A Report of the Committee on the Origins and Evolution of Life

The past decade has seen a remarkable revolution in genomic research, the discoveries of extreme environments in which organisms can live and even flourish on Earth, the identification of past and possibly present liquid-water environments in our solar system, and the detection of planets around other stars. Together these accomplishments bring us much closer to understanding the origin of life, its evolution and diversification on Earth, and its occurrence and distribution in the cosmos. A new multidisciplinary program called Astrobiology was initiated in 1997 by the National Aeronautics and Space Administration (NASA) to foster such research and to make available additional resources for individual and consortium-based efforts. Other agencies have also begun new programs to address the origin, evolution, and cosmic distribution of life. Five years into the Astrobiology program, it is appropriate to assess the scientific and programmatic impacts of these initiatives.

Edward J. Weiler, NASA’s associate administrator for the Office of Space Science, tasked the Committee on the Origins and Evolution of Life (COEL) with assessing the state of NASA’s Astrobiology¹ program and with providing by mid-2002 a report presenting the following:²

• An assessment of the direction of the NASA Astrobiology program;

• A survey of initiatives for seeking life in the universe conducted by other U.S. federal and nongovernmental groups; similar activities by foreign space agencies should also be considered;

• Identification of any enhancements to the U.S. program that might be warranted; and

• Recommendations for coordination of NASA efforts with those of other parties.

In preparing this study, the committee recognized that NASA’s Astrobiology program, and astrobiology as a novel intellectual endeavor, are still at an early stage of definition and development. Nevertheless, remarkable progress has been made over a short period of time in defining the key scientific questions, initiating research and training programs, and developing collaborations on a national and international scale. As this intellectual endeavor matures toward becoming a scientific field in its own right, continued effort must be exerted to involve the appropriate breadth of disciplines and diversity of novel techniques in astrobiological research. These may change with time as progress is made on the search for life elsewhere in the universe and for a deep understanding of how life originated on Earth and evolved over 4 billion years.

The 1998-1999 roadmap for the Astrobiology program is the product of a successful initial planning effort that shaped the scope of astrobiology and gave the research area a set of objectives to guide research funding and the assembly of research groups. As with every such initial effort, there is room for improvement. COEL finds the current roadmap to be too broad and not selective enough in defining these three categories: the central research goals of astrobiology, those goals that are peripheral to astrobiology but still may contribute, and those research areas that are genuinely outside astrobiology as an intellectually coherent study.

• NASA should more carefully craft its definition of astrobiology as a discipline whose central focus is a selected set of issues directly linked to the origin, evolution, and ubiquity of life in the cosmos.

• An important operational goal of astrobiology is to inform NASA missions with respect to the techniques and targets for the search for life elsewhere, and the search for clues to the steps leading to the origin of life on Earth.

• The core scientific areas within astrobiology ought to be specifically and selectively defined as those that deal with the origin, evolution, and occurrence of life in the cosmos as embraced in NASA’s research and analysis programs in the general areas of exobiology, evolutionary biology, planetary origin and evolution, cosmochemistry, and astronomical studies relating to the search for origins.

• Global change should be defined more carefully in the next roadmap with respect to the time scales that are relevant to the astrobiological goals of understanding environments conducive to the origin and evolution of life.

• A critical analysis should be undertaken of the relevance of microgravity research to the central scientific goals of astrobiology.

After almost 5 years of funded research within NASA’s Astrobiology program, enough additional evolution of astrobiology has occurred that a new roadmap will be of value. COEL understands that NASA is now undertaking a new roadmap planning process.

The ongoing roadmapping process for NASA’s Astronomical Search for Origins program, which concerns research into the origin and evolution of physical systems from cosmological to planetological scales, has the opportunity to address an area of concern that this committee considers in the body of this report in some detail: the relationship and interaction between the Astronomical Search for Origins and the Astrobiology programs (see Chapter 3). In particular, the research interactions between these two areas seem much weaker at present than they could be, and certainly much weaker than those between Astrobiology and the evolutionary biology or geobiological communities.

These limitations aside, the committee is impressed by the speed with which a community is being built in astrobiological research and education. Many of the standard indicators of the emergence of a bona fide new interdisciplinary field—journals, university programs, annual meetings, and so on—seem to suggest that Astrobiology is developing quickly and carving a special role for itself among NASA programs, and that an intellectually distinct discipline may be taking shape.

The enthusiasm and drive of scientists who have aligned their central research foci toward astrobiology, in particular those involved in the NASA Astrobiology Institute (NAI), made a deep impression on the committee. NASA Headquarters, NASA’s Ames Research Center, and key members of the scientific community have done a good job of initiating the institute, encouraging a broader community of astrobiology researchers, and developing and implementing training and degree programs. Nonetheless, certain issues need to be addressed to ensure long-term scientific and programmatic success.

NASA’s Astrobiology program has evolved, through the efforts of NASA Headquarters, into a tripartite structure of consortium science, individual principal investigator (PI) research, and technology-development programs. The highest-profile element is the NAI, originally conceived as a virtual institute relying on electronic communication technologies to allow extensive interactions between participating institutions (nodes) without geographic limitations. While the NAI has generated exciting and, in some cases, important research results even though it is less than 5 years old, the virtual institute development has lagged behind.

Because of the scale and high profile of its coordinated research, the NAI is important to the Astrobiology program. NASA has done a good job of publicizing NAI research and wrapping it into NASA planning for astrobiologically relevant missions. However, for astrobiology to mature as a long-term scientific field, NASA must also attract and recognize astrobiologically oriented researchers who are not affiliated with the NAI. Likewise, the NAI’s research programs and its ability to place graduates of its programs in positions beyond the existing NAI nodes depend on enhancing scientific collaborations with non-NAI scientists. To date, the NAI has not adequately fostered such collaborations.

The NAI itself should encourage collaborations not merely within the institute, but with outside investigators and facilities as well. A particularly important avenue for promoting cooperation has been the NAI’s role in the establishment of “focus groups“ to examine specific topical areas relevant to astrobiology. Membership on some, but not all, focus groups has been openly advertised and is available to all interested scientists.

The consortium-based nature of NAI research requires long periods for the full benefits of the research to be realized. At the same time, the introduction of new nodes can create novel opportunities for the institute. NASA’s challenge will be to balance these two kinds of opportunities appropriately over the lifetime of the NAI.

In addition to the NAI, a second important experiment in consortium science is the NASA Specialized Center of Research and Training (NSCORT) program at two institutions—the Exobiology Center at the University of California, San Diego, and the New York Center for Studies of the Origin of Life at Rensselaer Polytechnic Institute—the first of which has been in existence for a decade. NSCORT science is co-located at each institution (or confined to a small number of geographically adjacent institutions) rather than being collaborative between a larger number of geographically dispersed institutions as is the case with the NAI. The success of the older of the two NSCORT consortia in producing talented and accomplished graduates recommends this program, and COEL sees it as a worthy second element in the consortium science leg of the Astrobiology triad.

The research and analysis effort in the Astrobiology program is currently focused on the Exobiology program, which in many ways is the intellectual precursor of the Astrobiology program. The general merits of competitive research and analysis programs have been discussed in other National Research Council (NRC) reports,³ and in

Astrobiology they have an added benefit of extending research beyond NAI member consortia. Research and analysis is a key second leg of the triad of science and technology activities that foster this new research area, and it could be expanded modestly to the point at which it is comparable in size with the other components of the program.

COEL commends NASA for recognizing the long-term and continuing high value of research and analysis programs within and related to NASA Astrobiology. These and comparable programs are essential to the continued scientific vigor of astrobiology through the introduction of new ideas and researchers to the program.

COEL offers no advice on whether the Exobiology and Evolutionary Biology programs should be merged, except to point out that some programmatic advantage exists in maintaining the identity of the different disciplines through well-focused research and analysis programs.

Just as NASA’s Planetary Instrument Definition and Development Program (PIDDP) within the Solar System Exploration program has served to generate new ideas for flight instruments, so should the Astrobiology program contain a component for the development of new technologies relevant to the field. While the NAI is playing an important role in mission definition through its focus groups, a crucial additional component is a technology-development program for astrobiological instrumentation that might fly in space or be used to analyze samples and environments here on Earth.

• Although the Astrobiology program’s present level of involvement in flight missions is appropriate, NASA is cautioned against attempting to force the NASA Astrobiology Institute or other elements of Astrobiology into an artificially focused role of trying to design specific “astrobiology missions.“ While individual NAI investigators are encouraged to propose instrument concepts or whole Discovery-class (or equivalent) missions, NASA should be careful not to bias the usual peer-review selection process for instruments and missions by specially labeling proposals proffered by NAI investigators.

• NASA should continue the two astrobiology technology programs, Astrobiology Science and Technology Instrument Development, and Astrobiology Science and Technology for Exploring Planets, and in addition the Planetary Instrument Definition and Development Program (in the Solar System Exploration program) and the Extrasolar Planets Advanced Missions Concepts program (in the Astronomical Search for Origins program) as part of the efforts to detect life in this and other planetary systems.

Research efforts that are directly identified as astrobiology are dominated today by the biological and geological sciences. Yet the intellectual sphere covered by objectives in astrobiology includes much of the planetary sciences and the stellar and planetary aspects of the astronomical search for origins. Involvement of planetologists and astronomers has been hampered by a strong skepticism, even suspicion, in those communities regarding the scientific value of astrobiology as an intellectual endeavor. The committee believes that some of this skepticism will decline as astrobiology demonstrates results and as the future emerging field is better defined both intellectually and programmatically (that is, through future roadmaps). But there remains the difficulty of interaction between research areas whose techniques, technical language, and experimental approaches are very different. The long-term success of astrobiology in addressing its objectives will depend on a deeper and more extensive exchange of ideas with the traditional space sciences.

COEL commends NASA for developing a strong and well-balanced Solar System Exploration program that forms an important foundation for much of the central endeavor of astrobiology.

• The NASA Astrobiology Institute should initiate a much broader suite of focus group programs with planetary scientists, beyond those currently devoted to studies of Mars and Europa, to create a deeper level of mutual understanding and appreciation of the two research areas and to provide new perspectives for future solar system exploration.

• NASA should foster more extensive links between the Astrobiology and the Astronomical Search for Origins programs. In the short term, these linkages require cooperation between the NAI and major astronomical institutions, such as the Space Telescope Science Institute and universities with extensive astronomical programs, in creating joint workshops and focus groups to educate researchers in both areas and to initiate more extensive and novel research endeavors.

• Panels evaluating NAI membership proposals must be broadly constituted to ensure expert evaluation of research programs that are intellectually strong but have a discipline balance very different from that found in the existing NAI nodes.

• NASA should study the feasibility and desirability of creating and funding an institute, akin to the NAI, dedicated to consortium-based science and technology (e.g., involving multi-institution teams) related to the astronomical search for origins on the full range of spatial and temporal scales.

Other federal agencies besides NASA have played important and distinctive roles in the fostering of astrobiology. The National Science Foundation’s (NSF’s) Life in Extreme Environments (LExEn) program was vital in bringing talented biologists and physical scientists together to explore important problems in astrobiology outside the NAI itself. Moreover, the National Institutes of Health (NIH) is the wellspring from which comes much of the biological talent that NASA desires.

The Department of Energy (DOE) has a uniquely effective program for sequencing the genomes of microorganisms, many of which are of relevance to astrobiological research. NASA should strengthen its connection with the DOE to take advantage of the latter’s uniquely productive and broad gene-sequencing program. Similarly, the U.S. Department of Agriculture (USDA) has devoted considerable attention to sequencing the genomes of economically important plants and animals. These data are potentially important to astrobiologists for the information they may contain about long-term climate excursions. NASA should engage the USDA in the development of a program to enable astrobiologists to both interpret and use this record. As a basic rule, access of astrobiologists to genome-sequencing opportunities at other government agencies should be designed so as not to discourage or exclude access to other sequencing capabilities, including those in private industry.

Perhaps the most romantic venture in astrobiology is the search for extraterrestrial intelligence (SETI). This effort has had a checkered reception by scientists and federal lawmakers, with the result that the current efforts are almost entirely privately funded. The SETI Institute in Mountain View, California, the nexus of such efforts in the United States, has accomplished in a spectacular way the founding of a science institute and the procurement of stable private funding to carry on the search. Because world-class scientists lead the SETI Institute, it is a carefully designed effort and worthy of notice by the scientific community and relevant federal agencies.

The leadership of the SETI Institute has forged a unique endeavor out of private and public funds, maintained a high standard of scientific research through its peer-reviewed research activities, and articulated clearly and authoritatively the rationale for approaches to a comprehensive search for extraterrestrial intelligence.

International efforts in astrobiology have lagged behind those in the United States but are now beginning to gain momentum. While Europe has long had vigorous exobiology research efforts, it was the creation of the NAI that spurred the development of astrobiological institutes and consortia overseas. Notable among these are a large

research center in Spain and consortia in the United Kingdom, Australia, and across the European Union. The efforts of a handful of visionary scientists abroad and in the United States, working with the NAI as a catalyst, enabled these to be initiated. For joint endeavors in astrobiology between the United States and other countries to be fruitful, work will have to be undertaken by NASA to ease the strictures of technology transfer regulations.

COEL applauds the efforts of Spanish astrobiologists in creating a world-class astrobiology center, the Centro de Astrobiología (CAB), from the ground up. NASA and the NAI deserve credit for doing their part in fostering the growth of the CAB through encouragement and the creation of associate membership status for the CAB in the NAI.

The committee encourages NASA and the NAI to continue to seed efforts in astrobiology worldwide through the free exchange of scientific information, experimental techniques, and computational results. Association or affiliation with the NAI ought to be used as a tool to encourage international efforts in this regard, but it should be approached with care so as not to give the impression that the United States is in any sense pressuring other countries.

Finally, the committee notes that the International Traffic in Arms Regulations (ITAR) will continue to make it difficult for scientists to fully interact on astrobiology projects internationally. The changes to ITAR that came into force in April 2002 may ease this situation by making it clearer that fundamental research collaboration does not require an ITAR license and that the exchange of most forms of technical information in the public domain can proceed without impediment with nationals of NATO and a few other allied countries. Some problems remain, especially collaboration with foreign scientists and students from non-NATO countries, so it is important for NASA to continue to monitor the situation and to help ensure that ITAR does not have a suffocating effect on the free exchange of the results of space and biological sciences research.

The foundational questions that astrobiology addresses will not be answered in the short term. But as a coordinated, focused effort involving consortium- and individual principal investigator-driven science, as well as technology development, NASA’s Astrobiology program is well poised to catalyze fundamentally important discoveries concerning the origin of life, its distribution in the cosmos, and the long-term fate of life on Earth.

In the list below, COEL summarizes the overall problems that NASA’s Astrobiology program should address in the near future to ensure its own health:

• Definition of astrobiology and its goals. The widespread perception that astrobiology as both an intellectual endeavor and a NASA program is ill-defined continues to impair its interaction with related scientific disciplines.

• Evaluation of the impact of NAI on astrobiology. With one or two exceptions, the PIs of the current nodes, as well as the NAI director, argued that it was premature to assess how the NAI has affected astrobiology in ways that a standard research and analysis program could not have. This question will be asked with increasing urgency in the coming years, and before long the NAI must undertake a serious self-assessment to answer it.

• Review/retirement of existing programs. While the desire to maintain funding for excellent nodes is understandably strong, the mission of the NAI demands that new researchers and new institutions be brought into the NAI to expand the emerging field of astrobiology. A full recompetition at the end of each 5-year cycle, in which old and new consortia compete with each other, is the best way to accomplish this.

• Insularity of the NAI. The natural tendency for NAI consortia to see their scientific “universe“ as being within the NAI must continue to be resisted. The NAI should be a catalyst for interdisciplinary research in astrobiology among a much larger set of researchers than those who are members of NAI nodes.

• The “astro“ in astrobiology. Astronomy remains the key fundamental discipline that has yet to have a full impact on astrobiology. Efforts to better integrate astronomical research into the Astrobiology program require careful planning, as well as recognition that astronomical studies relating to the search for origins themselves constitute a discipline that is so active and expansive as to merit consideration of its own virtual institute, modeled on the NAI.

A Report of the Solar System Exploration Survey Committee

Solar system exploration is that grand human endeavor which reaches out through interplanetary space to discover the nature and origins of the system of planets in which we live and discover whether life exists beyond Earth. It is an international enterprise involving scientists, engineers, managers, politicians, and others, sometimes working together and sometimes in competition, to open new frontiers of knowledge. It has a proud past, a productive present, and an auspicious future.

Solar system exploration is a compelling activity. It places within our grasp answers to basic questions of profound human interest: Are we alone? Where did we come from? What is our destiny? Further, it leads to the creation of knowledge that will improve the human condition. Mars and icy satellite explorations may soon provide an answer to the first of these questions. Exploration of comets, primitive asteroids, and Kuiper Belt objects may have much to say about the second. Surveys of near-Earth objects and further exploration of planetary atmospheres will say something about the third. Finally, explorations of all planetary environments will result in a much-improved understanding of the natural processes that shape the world in which we live.

This survey was requested by the National Aeronautics and Space Administration (NASA) to determine the contemporary nature of solar system exploration and why it remains a compelling activity today. A broad survey of the state of knowledge was requested. In addition, NASA asked for identification of the top-level scientific questions to guide the ongoing program and a prioritized list of the most promising avenues for flight investigations and supporting ound-based activities. To accomplish this task, the Solar System Exploration Survey’s Steering Group and panels have worked with scientists, professional societies, NASA and NSF officials, persons at government and private laboratories, and members of the interested public. The remarkable breadth and diversity in the subject is evident in the panel reports that are contained in Part One of this survey. Together they strongly reinforce the idea that a high level integration of the goals, ideas, and requirements that exist in the community is essential if a practical exploration strategy for the next decade is to emerge. Such an integrated strategy is the objective of Part Two.

Based upon the material presented in Part One of this report, the Solar System Exploration Survey has identified four recurring issues, or crosscutting themes, that form an appropriate basis for an integrated strategy that can be realized by a series of missions to be flown over the next decade. The four crosscutting themes are as follows:

• The First Billion Years of Solar System History covers the formative period that features the initial accretion and development of Earth and its brethren planets, including the emergence of life on our globe. This pivotal epoch in the solar system’s history is only dimly glimpsed at present.

• Volatiles and Organics: The Stuff of Life addresses the reality that life requires organic materials and volatiles, notably liquid water. These materials originally condensed in the outer reaches of the solar nebula and were later delivered to the planets aboard organic-rich comets and asteroids.

• The Origin and Evolution of Habitable Worlds recognizes that our concept of the “habitable zone“ has been overturned, and greatly broadened, by recent findings on Earth and elsewhere throughout our galaxy. Taking inventory of our planetary neighborhood will help to trace the evolutionary paths of the other planets and the eventual fate of our own.

• Processes: How Planets Work seeks deeper understanding of the fundamental mechanisms operating in the solar system today. Comprehending such processes—and how they apply to planetary bodies—is the keystone of planetary science. This will provide deep insight into the evolution of all the worlds within the solar system and of the multitude of planets being discovered around other stars.

Devolving from these four crosscutting themes are 12 key scientific questions. These are shown in Table ES.1, together with the names of the facilities and missions recommended as the most appropriate activities to address these questions. The priority and measurement objectives of these various projects are summarized in the next section.

Progress on the tabulated scientific themes and key questions will require a series of spaceflights and supporting Earth-based activities. It is crucial to maintain a mix of mission sizes and complexities in order to balance available resources against potential schemes for implementation. For example, certain aspects of the key science questions can be met through focused and cost-effective Discovery missions (<$325 million), while other high-priority science issues will require larger, more capable projects, to be called New Frontiers. About once per decade, Flagship missions (>$650 million) will be necessary for sample return or comprehensive investigations of particularly worthy targets. Some future endeavors are so vast in scope or so difficult (e.g., sample return from Mars) that no single nation acting alone may be willing to allocate all of the resources necessary to accomplish them and the SSE Survey recommends that NASA encourage and continue to pursue cooperative programs with other nations. Not only is the investigation of our celestial neighborhood inherently an international venture, but also the U.S. solar system exploration program will benefit programmatically and scientifically from such joint ventures.

Discovery missions are reserved for innovative and competitively procured projects responsive to new findings beyond the nation’s long-term strategy. Such missions can satisfy many of the objectives identified by the individual panels in Part One. Given Discovery’s highly successful start, the SSE Survey endorses the continuation of this program, which relies on principal-investigator leadership and competition to obtain the greatest science return within a cost cap. A flight rate of no less than one launch every 18 months is recommended.

Particularly critical in this strategy is the initiation of New Frontiers, a line of medium-class, principal-investigator-led missions as proposed in the President’s FY 2003 budget. The SSE Survey strongly endorses the New Frontiers initiative. These spacecraft should be competitively procured, have flights every 2 or 3 years with a total cost capped at approximately twice that of a Discovery mission. Target selection should be guided by the list in this report.

Experience has shown that large missions, which enable detailed, extended, and scientifically multifaceted observations, are an essential element of the mission mix. They allow the comprehensive exploration of science targets of extraordinarily high interest. Comparable past missions have included Viking, Voyager, Galileo, and Cassini-Huygens. The SSE Survey recommends that Flagship (>$650 million) missions be developed and flown at a rate of about one per decade. In addition, for large missions of such inclusive scientific breadth, a broad cross section of the community should be involved in the early planning stages.

Programmatic efficiencies are often gained by extending operational flights beyond their nominal lifetimes. Present candidates for continuation include Cassini, projects in the Mars Exploration Program, and several Discovery flights. The SSE Survey supports the current Senior Review process for deciding the scientific merits of a proposed mission extension and recommends that early planning be done to provide adequate funding of mission extensions, particularly Flagship missions and missions with international partners.

Because resources are finite, the committee has prioritized all new flight missions within each category along with any associated activities. In order to assess priorities in the selection of particular missions it used the following criteria: scientific merit, “opportunity,“ and technological readiness. Scientific merit is measured by judging whether a project has the possibility of creating or changing a paradigm, whether the new knowledge it produces will have a pivotal effect on the direction of future research, and, finally, on the committee’s appraisal of how that knowledge would substantially strengthen the factual base of current understanding.

Because of wide differences in scope and the diverse circumstances of implementation, the committee, at NASA’s request, prioritizes only within the cost classes: small (<$325 million), medium ($325 million to 650 million), and large (>$650 million). Also, since the Mars Exploration Program line is already successfully established as a separate entity within NASA, its missions are prioritized separately.

The recommendations from the SSE Survey’s panels have been integrated with the solar system exploration program’s overall goals and key questions in order to arrive at the flight mission priorities listed in Table ES.2. The committee has included five New Frontiers missions in its priority list, recognizing that not all might be affordable within the constraints of the budgets available over the next decade.

EGE, a Flagship mission, will investigate the probable subsurface ocean of Europa and its overlying ice shell as the critical first step in understanding the potential habitability of icy satellites. While orbiting Europa, EGE will employ gravity and altimetry measurements of Europa’s tidal fluctuations to define the properties of any interior ocean and characterize the satellite’s ice shell. Additional remote-sensing observations will examine the three-dimensional distribution of subsurface liquid water; elucidate the formation of surface features, including sites of current or recent activity; and identify and map surface composition, with emphasis on compounds of astrobiological interest. Prior to Europa-orbit insertion, EGE’s instruments will scrutinize Ganymede and Callisto, moons that also may have subsurface oceans, thereby illuminating Europa’s planetary and astrobiological context. Europa’s thorough reconnaissance is a stepping-stone toward understanding the astrobiological potential of all icy satellites and will pave the way for future landings on this intriguing object.

KBP will be the first spacecraft dispatched for scientific measurements within this remote, entirely unexplored outer half of the solar system. KBP will fly past Pluto/Charon and continue on to reconnaissance several additional Kuiper Belt objects (KBOs). KBP’s value increases as it observes more KBOs and investigates the diversity of their properties. This region should be home for the most primitive material in the solar system. KBP will address the prospect that KBOs have played a role in importing basic volatiles and molecular stock to the inner solar system, where habitable environments were created. The committee anticipates that the information returned from this mission might lead to a new paradigm for the origin and evolution of these objects and their significance in the evolution of objects in other parts of the solar system.

SPA-SR will return samples from the Moon in order to constrain the early impact history of the inner solar system and to comprehend the nature of the Moon’s upper mantle. The South Pole-Aitken Basin, the largest impact structure known in the solar system, penetrates through the lunar crust. It is stratigraphically the oldest and deepest impact feature preserved on the Moon. The SPA-SR will help determine the nature of the differentiation of terrestrial planets and provide insight into the very early history of the Earth-Moon system. SPA-SR will also enable the development of sample acquisition, handling, and return technologies to be applied on other future missions.

JPOP will determine if Jupiter has a central core, a key issue that should decide between the two competing scenarios for the planet’s origin. It will measure water abundance, which plays a pivotal role in understanding giant planet formation. This parameter indicates how volatiles (H₂O, CH₄, NH₃, and H₂S) were incorporated in the giant planets and, more specifically, the degree to which volatiles were transported from beyond Neptune to the inner solar system. The mission will probe the planet’s deep winds to at least the 100-bar pressure level and may lead to an explanation of the extreme stability of the cloud-top weather systems. From its cloud-skimming orbit, JPOP will investigate the fine structure of the planet’s magnetic field, providing information on how its internal dynamo works. Lastly, the spacecraft will repeatedly visit the hitherto unexplored polar plasma environment, where magnetospheric currents crash into the turbulent atmosphere to generate powerful aurorae.

On descent, VISE will make compositional and isotopic measurements of the atmosphere and—quickly—of the surface. It will loft a core sample from Venus’s hellish surface to cooler altitudes, where further geochemical and mineralogical data will be obtained. VISE will provide key measurements of the lower atmosphere and of surface-atmosphere interactions on Earth’s would-be twin. The project will elucidate the history and stability of

Venus’s atmospheric greenhouse and its bizarre geological record. It will also advance the technologies required for the sample return from Venus expected in the following decade.

CSSR will collect materials from the near surface of an active comet and return them to Earth for analysis. These samples will furnish direct evidence on how cometary activity is driven. Information will be provided on the manner in which cometary materials are bound together and on how small bodies accrete at scales from the microns to centimeters. By comparing materials on the nucleus against the coma’s constituents, CSSR will indicate the selection effects at work. It will also inventory organic materials in comets. Finally CSSR will yield the first clues on crystalline structure, isotopic ratios, and the physical relationships between volatiles, ice, refractory materials, and the comet’s porosity. These observations will give important information about the building blocks of the planets.

Recommendations for small missions include a series of Discovery flights at the rate of at least one every 18 months and an extension to the Cassini-Huygens mission (Cassini Extended) presuming that the nominal mission is successful. Discovery missions are, by intent, not subject to long-term planning. Rather, they exist to create frequent opportunities to fly small missions addressing fundamental scientific questions and to pursue new research problems in creative and innovative ways.

For Mars exploration, the SSE Survey endorses the current science-driven strategy of seeking (i.e., remote-sensing), in situ measurements (science from landers), and sampling to understand Mars as a planet, understand its astrobiological significance, and afford unique perspectives about the origin of life on Earth. The evolution of life and planetary environments are intimately tied together. To understand the potential habitability of Mars, whether it has or has not supported life, we must understand tectonic, magmatic, hydrologic evolution as well as geochemical cycles of biological relevance. The return of materials from known locations on Mars is essential to address science goals, including those of astrobiology, and to provide the opportunity for novel measurements, such as age dating and ultimate ground truth.

MSL will conduct in situ investigations of a water-modified site that has been identified from orbit. It will provide ground truth for orbital interpretations and test hypotheses for the formation of geological features. The types of in situ measurements, possible include atmospheric sampling, mineralogy and chemical composition, and tests for the presence of organics. The mission should either drill to get below the hostile surface environment, or have substantial ranging capability. While carrying out its science mission, MSL should test and validate technology required for later sample return.

MLN is a grid of science stations making coordinated measurements around Mars’s globe for at least 1 martian year. The highest priority objectives for network science on Mars are the determination of the planet’s internal structure, including its core; the elucidation of surface and near-surface composition as well as thermal and mechanical properties; and extensive synoptic measurements of the atmosphere and weather. In addition, heat flow, atmospheric gas isotopic observations (to constrain the size of currently active volatile reservoirs), subsurface oxidizing properties, and surface-atmosphere volatile exchange processes will be valuable. This mission will complement the much more limited and localized French NetLander that will have four probes spaced across Mars’s equatorial regions.

MSR is required to perform definitive measurements to test for the presence of life, or for extinct life, as well as to address Mars’s geochemical and thermal evolution. Further, Mars’s atmosphere and now frozen hydrosphere will require highly sophisticated measurements and analytical equipment. To accomplish key science goals, samples must be returned from Mars and scrutinized in terrestrial laboratories. For these reasons, the SSE Survey recommends that NASA begin its planning for MSR missions so that their implementation can occur early in the decade 2013-2023. Current studies of simplified Mars sample-return missions indicate that such missions are now within technological reach. Early on, NASA should engage prospective international partners in the planning and implementation of MSR.

Mars Scout missions are required to address science areas that are not included in the core program, and to respond to new discoveries derived from current and future missions. A series of such small (<$325 million) missions should be initiated within the Mars program for flights at alternating Mars launch opportunities. This program should be modeled on the Discovery program.

Mars Upper Atmosphere Orbiter (MAO) is a small mission dedicated to studies of Mars’s upper atmosphere and plasma environment. This mission would provide quantitative information on the various atmospheric escape fluxes, thus quantifying current escape rates and providing a basis for backwards extrapolation in our attempt to understand the evolution of Mars’s atmosphere.

A significant investment in advanced technology development is also needed for the recommended new and future flight missions to better succeed. Table ES.3 identifies a number of important areas in which technology development is appropriate. The SSE Survey recommends that NASA commit to significant new investments in advanced technology in order that future high-priority flight missions can succeed.

In an era of competitively selected missions for space exploration, it will continue to be necessary to improve the technical expertise and infrastructure of organizations providing the vital services that enable the planning and operation of all solar system exploration missions.

For missions to be the most productive scientifically, we must ensure a level of funding that is sufficient for not only the successful operation pof the flight but also for the contemporaneous analysis of the data and the publication of scientific results. Moreover, our mission priorities rest on a foundation that must be secured and buttressed. This foundation includes fundamental research, technology development, follow-on data analysis, ground-based facilities, sample-analysis programs, and education and public outreach activities.

The entire pipeline that brings data from distant spacecraft to the broad research community must be systematically improved. Insufficient downlink communications capacity through the Deep Space Network (DSN) currently restricts the return of data from all missions, as occasionally does the DSN’s limited geographical coverage. The DSN needs to be continually upgraded as new technologies become available and system demands increase.

Once data are on the ground, they must be swiftly archived in a widely accepted and usable format. The Planetary Data System (PDS) should be included as a scientific partner at the very early stages of missions; its must be sized to accomplish its future tasks. In order to utilize the returned information effectively, analysis programs ought to be in place to fund investigators immediately upon delivery of ready-to-use data to the PDS. Data-analysis programs should be merged across lines (e.g., Discovery, New Frontiers) rather than tied to individual missions.

A healthy research and analysis program (R&A) is the most basic requirement for a successful program of flight missions. The SSE Survey recommends an increase over the decade in the R&A programs at a rate above inflation that parallels the increase in the number of missions, amount of data, and diversity of objects studied. Previous NRC studies showed that after a serious decline in the early to mid-1990s, the overall funding for R&A programs in NASA’s Office of Space Science has in recent years climbed to approximately 20 percent of the overall flight mission budget. Figures supplied by NASA’s Solar System Exploration program show that the corresponding value for planetary activities is currently closer to 25 percent and is projected to stay at about this level for the next several years. The SSE Survey believes that this is an appropriate allocation of resources.

NASA’s Astrobiology Program has appropriately become deeply interwoven into the solar system exploration research and analysis program. The SSE Survey encourages NASA to continue the integration of astrobiology science objectives with those of other space science disciplines. Astrobiological expertise should be called upon when identifying optimal mission strategies and design requirements for flight-qualified instruments that address key questions in astrobiology and planetary science.

Ground-based telescopes have been responsible for several major discoveries in solar system exploration during the past decade. Moreover, many flight missions are greatly enhanced as a result of extensive ground-based characterization of their targets. The SSE Survey recommends that NASA partner equally with the National Science Foundation to build and operate a survey facility, such as the Large-Aperture Synoptic Survey Telescope (LSST) described in Astronomy and Astrophysics in the New Millennium to ensure that LSST’s prime solar system objectives are accomplished. Other powerful new facilities highlighted in that report—e.g., the Next Generation Space Telescope—should be designed, where appropriate, to be capable of observing moving solar system targets. In addition, NASA should continue to support ground-based observatories for planetary science, including the planetary radar capabilities at Arecibo and Goldstone, the Infrared Telescope Facility, and shares of cutting-edge telescopes such as Keck, as long as they continue to be critical to missions and/or scientifically productive.

In anticipation of the return of extraterrestrial samples from several ongoing and future missions, an analogue to the data pipeline must be developed for cosmic materials. The SSE Survey recommends that well before cosmic materials are returned from planetary missions, NASA establish a sample analysis program to support instrument development, laboratory facilities, and the training of researchers. In addition, planetary protection requirements for missions to worlds of biological interest will require investments, as will life-detection techniques, sample quarantine facilities, and sterilization technologies. NASA’s current administrative activities to develop planetary protection protocols for currently planned missions are appropriate.

Education and Public Outreach activities connect solar system exploration with its ultimate customers—the tax-paying public—and as such are an extremely important component of the program. Solar system exploration captures the imagination of young and old alike. By correctly illustrating the scientific method at work and demonstrating scientific principles, the planetary science community’s efforts in communicating with students and lay people can be influential in helping to improve science literacy and education. In most implementations today, planetary scientists and education specialists work hand in hand to derive innovative and effective activities for

communicating solar system exploration to students, teachers, and the public. Although some problems remain, this program is well managed and is on a solid foundation.

For nearly 40 years, the U.S. solar system exploration program has led to an explosion of knowledge and awe of our celestial neighborhood as ground-based telescopes and spacecraft have become much more capable while reaching out further from Earth. We are now poised to address issues about our origins that have puzzled our forebears since civilization’s beginning. Answers to profound questions about our origins and our future may be within our grasp. This survey describes an aggressive and yet rational strategy to deepen our analysis of such questions and finally resolve many long-standing mysteries during the next decade.

A Report of the Committee to Review NASA’s Earth Science Enterprise Applications Plan

The Earth Science Enterprise Applications Strategy for 2002-2012 (the Applications Plan¹) was prepared in January 2002. In response to a request from NASA, the Committee to Review NASA’s Earth Science Applications Plan was established by the Space Studies Board of the National Research Council. The committee was asked to assess the following: (1) the overall goals, strategy, and approach for the ESE Applications Program, (2) the planning and prioritization process, operations concept, expected program results or deliverables, and performance measures, and (3) how well the approach outlined in the plan will serve to advance NASA’s stated goals and objectives for the ESE Applications Program.

The Applications Plan consists of a preface; four main sections that address (1) program vision, missions, and goals as well as context with respect to the broader ESE program, (2) program planning strategy, which includes a discussion of the priorities for selection of candidate applications, (3) program operations, which includes aspects of program management and implementation, and (4) performance evaluation measures; and a short summary and several appendices. In briefings to the committee, NASA representatives elaborated on the material that appears in the Applications Plan and noted that NASA’s applications strategy has evolved and is expected to continue to evolve over time.

In briefings to the committee, Office of Management and Budget and NASA officials noted that in the 1990s accelerating the U.S. commercial remote sensing industry was a NASA priority, and later in the period the ESE Applications Program emphasized pilot projects and demonstrations at the state and local level. The efforts, which were often funded via grants to state, local, tribal, and university entities, focused on building government-to-citizen relationships. The current NASA applications strategy adopts a modified approach that adds an emphasis on national (as opposed to local) “benchmark” applications that utilize NASA partnerships with other federal agencies (“government-to-government-to-citizen relationships”). According to NASA officials, this modified strategy will capitalize on NASA systems engineering expertise and NASA data and scientific capability to help NASA’s federal partners develop decision support tools for a variety of specific applications. NASA refers to the former strategies as the “heritage program” and the current, augmented approach as the “go forward” strategy.

NASA described to the committee a set of key strategic principles on which the ESE Applications Program will be founded in the future. They are as follows:

• Extend the use of NASA/ESE climate, weather, and natural hazards research for the social and economic benefit of the nation.

• Focus on application areas of demonstrated national significance.

• Define specific applications through joint projects with users.

• Provide a systems engineering role for the user community—data and measurements, modeling, and decision support.

• Rely on users to supply the operational environment and operational support.

The Applications Plan describes a process whereby candidate applications are selected based on their potential to address national needs, after which the candidate areas are prioritized on the basis of the following eight criteria, listed in descending order of importance:

1. Socio-economic value,

2. Application feasibility,

3. Response to executive or legislative branch direction,

4. Appropriateness for NASA,

5. Opportunity for collaborative partnership,

6. Scientific and technological readiness,

7. Program balance, and

8. Cost and budget context.

The January 2002 draft of the Applications Plan includes an appendix that lists five representative examples of applications topics and federal agency partners—wild fire management with the U.S. Forest Service, coastal beach mapping with NOAA, agriculture crop greenness and production assessment with the U.S. Department of Agriculture (USDA), hurricane track prediction with NOAA, and aviation safety through synthetic vision systems with the Federal Aviation Administration (FAA). In briefing the committee NASA indicated that this list has been expanded to the following set of 12 areas of national priority for initial emphasis in the program:

1. Enhanced weather prediction for energy forecasting,

2. Weather and climate prediction for agricultural competitiveness,

3. Carbon sequestration assessment for carbon management,

4. Digital atmosphere and terrain visualization for aviation transportation safety,

5. Early-warning systems for air and water quality for homeland security,

6. Environmental indicators for community growth management,

7. Integrated hurricane and flooding prediction for community disaster preparedness,

8. Early-warning systems for vector-borne infectious diseases for public health,

9. Environmental indicators for coastal management,

10. Environmental models for biological invasive species,

11. Water-cycle assessments for water management and conservation, and

12. Regional, national, and international atmospheric measurements and predictions for air quality management.

NASA officials told the committee that the initial applications areas have been selected, partners have been identified, and initial roadmaps or program plans have been prepared. They reported that implementation approaches are being formulated and that the next steps will be to prioritize the selected areas and establish formal teaming arrangements with partners. The Applications Plan concludes with a discussion of plans for program evaluation in compliance with the Government Performance and Results Act, and it lists a set of “inputs, outputs, outcomes, and impacts” by which NASA will judge success.

The committee was impressed by NASA’s commitment to a strong applications program that will have a national impact. The Applications Plan contains many sections that serve as a good starting point for demonstrating that intent via a process that recognizes partnerships and shared applications of research results as critical contributions toward meeting NASA’s mission. A number of aspects of the Applications Plan are especially noteworthy. Notable examples of elements of the Applications Plan that the committee applauds include the following:

• The mission statement for the ESE Applications Program is a good broad-based statement.

• The process of interacting with other federal agencies to reach a diverse group of users is a viable and appropriate avenue to pursue.

• The management approach and prioritization of criteria for evaluating candidate applications areas are well reasoned.

• The itemization of action steps is valuable for the overall process and strategy.

• The science is linked with the decision-making process using decision support systems.

While the Applications Plan does not have fundamental weaknesses, the committee makes a series of recommendations for its improvement. Some overarching themes have been drawn from committee discussions. They are listed here first either because they recurred throughout the document evaluation process, and/or because they stand as general guidance and feedback to NASA regarding ways to strengthen the overall NASA applications strategy.

• The ESE Applications Program needs a period of stability and consistency of at least 5 years so that managers, partners, and applications users can have time to implement the NASA applications strategy and bring proposed applications initiatives to fruition. Both NASA representatives and officials from outside the agency noted that earlier changes in emphasis had unintended consequences. The Applications Plan should strive to reinforce effective past practices and demonstrate linkages to successful data application strategies. The current draft of the Applications Plan lacks sufficient language regarding how the NASA applications strategy will build on past approaches and projects, even as the Applications Plan retains a forward-looking agenda that remains its primary focus.

• The plan should address NASA’s ongoing commitment to providing data, models, and infrastructure support for operational solutions needed to attain the 2010 goals.

• Overall, the Applications Plan needs a clearer sense of connectivity in several different directions. This could be achieved by showing the linkages of (a) past strategies to the current strategy (as noted above), (b) the ESE Applications Program to other ESE programs, (c) the NASA applications strategy’s links to implementation and budgeting processes, and (d) NASA roles and responsibilities with respect to those of partners (see below).

• The theme of partnerships has been invoked in the NASA applications strategy, but it has not been fully realized in definition, scope, or practice. For example, the Applications Plan would benefit from a description of how the needs of partner federal agencies will be identified and when in the process of transition from research to operations these processes will be initiated. The opening section of the Applications Plan should document efforts by NASA to involve partners in the development of the NASA applications strategy itself, not only to demonstrate credibility, but also to reinforce NASA’s commitment to sharing credit as well as information.

  The relationship between partnering and implementation of applications is underdeveloped. Without a clear statement regarding the role of partners in the implementation of the NASA applications strategy and the application of data, the partnering function will resemble a “hand-off” rather than an inclusive, interactive, and collaborative process. Further, the establishment of a feedback mechanism should be an important concept within the partnerships that helps to define mutually agreed upon success/transition criteria or metrics. Such feedback should improve collaboration regarding next steps, suggest revisions for improving ineffective existing steps, and contribute to defining needs for future science research. The committee believes that the importance of end users and the private sector’s role as a performer or as a partner should also be prominently featured. Illustrative examples of past success would be useful.

  The Applications Plan’s references to eight large clusters of stakeholder groups may be an unwieldy way to reach potential partners, running the risk of over-generalization and promoting “sampling” as opposed to true partnering. The accomplishment of goals as outlined in Table 1 of the document will depend on other federal agency action as much as action by NASA; more details are needed regarding how partner participation is ensured, how it is measured, and how to create “buy-in.”

  Finally, while the Applications Plan cites partnerships that relate almost exclusively to federal partners, the committee could not determine whether NASA also contemplates primary partnerships with non-federal partners or whether those partnerships will be only or mainly derivative. The committee believes that NASA should recruit partners using open announcements in an effort to expand the pool of partners.

• The Applications Plan could benefit from more attention to its intended audience. The document does not clearly specify an intended audience, beyond all-inclusive references to the American people. More importantly, while the intended audience may be reasonably knowledgeable people within OMB and

Congress, the Applications Plan will be read by a broader audience and therefore must provide greater context, perhaps at the expense of brevity, to facilitate better communication and avoid generating unintended consequences or misinterpretations.

• The Applications Plan needs to articulate a strategy for translating concepts into more tangible actions. A number of concepts could benefit from further development and explanation. Among the needed improvements are a stronger opening statement as to why the strategy is necessary and why this particular strategy is the best approach; an explanation of how the plan reflects consultation with non-NASA stakeholders; a more specific identification of who the program is for and how it is to be accomplished, including the role of Earth Science Information Partners Regional Earth Science Applications Centers, and others; a greater distinction between the general mission of ESE and the more specific mission of the ESE Applications Program; a specific rationale for conveying a 10-year commitment for the strategy; clarification as to whether the strategy employs a “push” or “pull” (or “driver vs. response”) approach with partners, whether partners are primarily federal agencies or others such as local governments are also included, and whether demonstration projects are still part of this strategy; responsibility of partners to co-fund; and clarification of the mechanism or strategy for the transfer of activity from NASA to its partners.

  Finally, it would be most helpful if examples were given to illustrate the successful functioning of the process. Options for illustrative examples include a series of graphic diagrams, or tracing one example throughout the Applications Plan to illustrate how the various processes would apply.

On the whole, the recommendations of the committee are designed to increase understanding, eliminate confusion, and improve the acceptance of the NASA applications strategy by a wide audience of potential partners, users, and other interested parties. The committee endorses the efforts of NASA to explore new and improved approaches to its function of applying Earth sciences information in a useful and collaborative fashion.

A Report of the Committee on Precursor Measurements Necessary to Support Human Operations on the Surface of Mars

This study, commissioned by the National Aeronautics and Space Administration (NASA), examines the role of robotic exploration missions in assessing the risks to the first human missions to Mars. Only those hazards arising from exposure to environmental, chemical, and biological agents on the planet are assessed.

To ensure that it was including all previously identified hazards in its study, the Committee on Precursor Measurements Necessary to Support Human Operations on the Surface of Mars referred to the most recent report from NASA’s Mars Exploration Program/ Payload Analysis Group (MEPAG) (Greeley, 2001). The committee concluded that the requirements identified in the present NRC report are indeed the only ones essential for NASA to pursue in order to mitigate potential hazards to the first human missions to Mars.

Even though NASA is actively pursuing a Mars exploration program, it is not yet actively pursuing a human mission to Mars, and there is no officially selected reference human exploration mission. Accordingly, the committee determined that it might best assist NASA by assuming that a long-stay mission to Mars will take place, as such a mission would levy the more stringent demand for the safety of astronauts while in the Martian environment. The reader should not conclude that this assumption implies an endorsement of the long-stay mission as a baseline mission, nor that the committee concluded that the long-stay mission is, in total, the least hazardous option.

In its review of the Mars robotic program, the committee found that NASA has done an excellent job of designing science rovers capable of operating on the surface of Mars. The committee believes, however, that the engineering knowledge being gained from the science rover experience will not scale up nor will it easily apply to human assistant rovers or larger human transport rovers. Furthermore, the committee notes that current science rover activities do not provide an adequate research base for the development of rovers needed for the human exploration of Mars.

NASA has allocated risk factors and reliability requirements for missions in low Earth orbit and for the International Space Station but has not done so for missions traveling beyond Earth orbit.

The concept of acceptable risk involves ethical, psychological, philosophical, and social considerations. The committee relied instead on standard risk sources. In reviewing the toxicology risk estimates for toxic metals, the committee chose to use an acceptable risk range (ARR) rather than a single risk level. In this report, the ARR for developing cancer as a result of exposure to toxic metals is between 1 in 10,000 and 1 in 100,000. The committee understands certain risks may overshadow others. Regardless of the large difference between the risk of getting fatal cancer from radiation and the cancer risk from exposure to toxic metals, it is prudent to reduce risk in all areas that are amenable to such reductions. It is important to reduce risks in areas that are reasonably achievable, as there can be synergistic effects of combined hazards.

The committee categorized the hazards on Mars by their sources, or causes. It specifically defined the physical hazards on Mars separately from the chemical and biological hazards, because physical hazards can threaten crew safety by physically interacting with humans or critical equipment, resulting, for example, in impact, abrasion, tip-over (due to an unstable Martian surface), or irradiation.

To ensure safe landing and operations on the surface of Mars, it is necessary for the landing site and the topography of the anticipated surface operation zone to be fully characterized with high-resolution stereoscopic imaging. The operation zone is the area around the landing site defined by the anticipated range of operations of extravehicular activities (EVAs), including the use of human transport and/or science rovers. The level of resolution required of this imaging will be determined by the capabilities of the equipment to be used on the surface.

The abrasive properties of rocks on Mars, including hardness and surface roughness (as dictated by rock grain size and shape), are unknown. The committee believes that, even faced with this lack of knowledge, NASA can still design systems by making certain educated assumptions about the rocks on Mars. For this reason, no further in situ experiments to determine the abrasive properties of Martian rocks are required.

Airborne dust presents a potentially significant hazard to human operations on the surface of Mars. Dust intrusion and accumulation will need to be continuously monitored and will require well-designed filter systems and periodic housecleaning. After reviewing NASA’s experience with dust on the Moon and Mars, the committee is confident that NASA engineers and scientists will be able to design and build systems to mitigate the hazards posed by airborne dust on Mars. Some systems that would be used on the first human mission can be designed either by employing what is currently known about Mars dust or by assuming a worst-case scenario in the design process.

The present Mars soil simulant that has been developed and characterized by NASA for engineering (JSC Mars-1: Martian Regolith Simulant) is not adequate for testing mechanical systems for human missions to Mars. However, the committee does not recommend that any precursor in situ measurements be taken on Mars to characterize the mechanical and abrasive properties of airborne dust. Rather, it expects that an appropriate simulant would adequately stress the design of any mechanical and seal systems that will be used during a human mission to Mars. It is critical, however, to fully characterize the adhesive properties of airborne dust in order to design systems that minimize the risk of failure resulting from dust accumulation.

The dry conditions and uncertainty about conductivity, charging, and discharging rates in the Mars environment create uncertainties about electrostatic effects on human operations in the Mars environment. However, even given the potential hazards, the committee believes that the risk to humans from electrostatic charging on the surface of Mars can be managed through standard design practice and operational procedures.

The committee believes that in light of the low dynamic atmospheric pressures experienced on Mars, no further characterization of wind speed on Mars is required prior to the first human mission. The surface winds are sufficiently characterized to allow system designers to ensure human safety on the planet by means of robust designs.

Radiation exposure in space will be a significant and serious hazard during any human expedition to Mars. There are two major sources of natural radiation in deep space: sparse but penetrating galactic cosmic radiation (GCR) and infrequent but very intense solar particle events (SPEs) associated with solar storms.

There have been no direct measurements of the radiation environment on the surface of Mars. Rather, the radiation environment is estimated using computer codes that model the transport of the deep space radiation through the Martian atmosphere and after its interactions with the Martian surface. Because of the central role of radiation transport and absorbed dose models in the planning and design of human missions to Mars, it is important that the code predictions be validated by means of a precursor experiment on the surface of Mars. Radiation risk mitigation strategies will be an integral part of overall mission design and planning. Should the results of the in situ experiment prove that the radiation transport models are flawed, more time will be needed to adjust the models to account for the differences between the models and the measurement.

In addition to the hazards from materials on Mars interacting dynamically with humans or critical systems, the committee has also assessed hazards associated with the chemical reactivity of materials on Mars.

Some dust and soil will in all probability be brought into the habitat through the airlock by returning astronauts, as was the case during the Apollo missions to the Moon. The committee has concluded that Martian airborne dust could present the same chemical hazards as Martian soil, so soil and dust should be characterized in the same way. In choosing the “worst“ toxic chemical hazards to humans, the committee considered inorganic substances separately from organic substances. With respect to inorganic substances, it identified certain toxic metals as the worst threat to humans at the lowest concentrations.

Soil and airborne dust on Mars could contain trace amounts of hazardous chemicals, including compounds of toxic metals, which are known to cause cancer over the long term if inhaled in sufficient quantities. If NASA protects astronauts against the risk of developing cancer in the long term as a result of having been exposed to particulate matter on Mars, NASA will also be protecting astronauts from acute and short-term noncancer effects that could potentially interfere with mission success. While the committee is confident in its knowledge of the possible concentrations of most toxic metals on Mars, the committee believes the uncertainty surrounding the amount of toxic hexavalent chromium (Cr VI) on Mars warrants a precursor measurement. Hexavalent chromium on Earth is very rare in natural materials, but the great abundance of chromium (in unknown form) on the surface of Mars, combined with the high oxidation state of Martian soil, suggests that hexavalent chromium might be present in small but potentially hazardous amounts.

The committee believes that NASA can provide filtration systems capable of minimizing the hazards of exposure to toxic elements, including hexavalent chromium, arsenic, and cadmium, that are present at concentrations of less than 150 ppm.

However, if a filtration system cannot be designed to limit the average astronaut respirable particulate inhalation exposure to 1 milligram of particulate matter per cubic meter of air (mg/m³) in the habitat, then a sample of airborne dust, taken from the Martian atmosphere, and soil must be analyzed for toxic metal concentrations. The level of analytical precision required for this measurement will be dictated by the filtration capability of the astronauts’ habitat.

It should be very clear to the reader that, in the view of the committee, the 1 mg/m³ specification is the maximum acceptable respirable particle average concentration to which astronauts should be exposed. This concentration level will protect astronauts from exposure to toxic metals, which—of all inorganic chemicals—the committee considers to pose the greatest health risk to astronauts. Filtering at or below the recommended 1 mg/m³ average with a 1.5 mg/m³ peak concentration should be readily achievable for NASA. Indeed, to minimize risks from exposure, the committee strongly believes that filtering should be implemented below 1 mg/m³, to as low a concentration as is reasonably achievable in the Martian habitat.

It is essential that NASA implement proper humidification in conjunction with the filtration system as part of habitat atmosphere conditioning to mitigate the threat of strong oxidants in Martian soil and airborne dust. The committee concluded that even if strong oxidants are present, there will be negligible risk associated with oxidation on the Martian surface if the proper humidification systems are in place and the particulate level is maintained at 1 mg/m³ or less.

However, even with the filtering systems in the habitat as discussed above, the filtration level may not be stringent enough to protect astronaut health and critical mechanical equipment from dust and soil that are extremely acidic. There are high concentrations of sulfur and chlorine in Martian soil, which implies the possibility of acidity in both the soil and airborne dust (Clark et al., 1982; Wanke et al., 2001). When inhaled by astronauts, acidic soil and dust could degrade their lung tissue and, if humidified and allowed to penetrate control units inside the habitat, could corrode sensitive critical equipment, such as control circuits.

If NASA decides not to implement the necessary engineering controls or for other science-related reasons chooses to measure the oxidation properties of Martian airborne dust and soil, then the measurement should be performed on the surface of Mars rather than via a sample return.

Certain organic compounds can be highly toxic to humans, even if those compounds are not associated with a life-form, and the threat should be evaluated in planning the first human mission to Mars. Any hazard from organic compounds would most likely come from handling subsurface samples that might contain organic compounds. The committee concludes that if organic carbon is present at a concentration of more than 150 ppm in soil to which astronauts might be exposed, a possible threat exists. Filtration systems that reduce astronaut exposure to organic carbon to concentrations less than 150 ppm would mitigate this threat. If experiments determine that organic carbon is present in concentrations greater than 150 ppm, the subsurface soil should be considered a toxic hazard until proven otherwise. The need to assess the potential threat posed by a hazardous life-form consisting of organic carbon requires a more stringent measurement of organic carbon concentration.

The Martian atmosphere, when mixed in small amounts with the habitat atmosphere, does not pose a toxic risk for astronauts, and no further characterization is required before the first human mission takes place. The primary hazardous components are easily removed by standard cabin-atmosphere conditioning systems.

The committee was charged with addressing issues of biological risks on Mars from two perspectives: (1) ensuring the safety of astronauts operating on the surface of Mars and (2) ensuring the safety of Earth’s biosphere with respect to potential back-contamination from returning human missions.

The probability that life-forms exist on the surface of Mars (that is, the area exposed to ultraviolet radiation and its photochemical products) is very small. However, as a previous NRC study (NRC, 1997) notes, there is a possibility that such life-forms exist there “in the occasional oasis,” most likely where liquid water is present, and, furthermore, that “uncertainties with regard to the possibility of extant Martian life can be reduced through a program of research and exploration.”

This charge to the committee results in a dilemma. How can NASA use human ingenuity and creativity on Mars to search for life when that life (if it exists) may pose a threat to astronaut health and safety (and therefore the success of a human mission) as well as to Earth’s biosphere?

The committee believes it is highly unlikely that infectious organisms are present on Mars. Nevertheless, once an astronaut has been directly exposed to such life, it would be very difficult, to the point of being impractical, to determine conclusively that the astronaut would not pose a contamination threat to Earth life. In such an event, NASA might be faced with requiring quarantine and surveillance of returning astronauts until it is determined that a threat no longer exists.

While the threat to Earth’s ecosystem from the release of Martian biological agents is very low, “the risk of potentially harmful effects is not zero“ and cannot be ignored (NRC, 1997). NASA should assume that if life exists on Mars, it could be hazardous to Earth’s biosphere until proven otherwise. As such, NASA should ensure proper quarantine or decontamination of equipment that may have been exposed to a Martian life-form.

To protect Earth from contamination by Martian life-forms aboard a returning human mission and astronauts while they are on the surface of Mars, the committee recommends that NASA employ the concept of zones of minimal biologic risk (ZMBRs) for astronaut exploration. These zones, operational areas on the surface of Mars, would be determined, to the maximum extent practicable, to be devoid of life or to contain only life-forms that would not be hazardous to humans or Earth’s biosphere.

The committee recognizes that the requirement to establish and operate in a ZMBR, while intrinsic to the study charter to manage risk to astronauts, may be in conflict with one of the primary goals of the exploration of Mars: to find extraterrestrial life.

To establish a ZMRB, NASA should first attempt to determine whether or not life exists (1) at the physical locations where astronauts will be operating and (2) in the Martian material to which astronauts will be exposed. The establishment of a ZMBR might initially be based on an in situ testing protocol conducted prior to the first human visit. Once a landing site is established as a ZMBR, the astronauts can land and freely operate within it.

While some have suggested that non-carbon-based life might be present on Mars, this committee agrees with assumptions made by previous NRC committees that should hazardous life exist on Mars it would be carbon-based and thus would contain organic compounds (NRC, 2002a, 2002b). A search for life should therefore include a search for organic carbon. The detection of organic carbon might indicate the presence of life-forms.

If a sample of Martian soil and airborne dust is returned to fulfill this requirement, the returned sample should be considered hazardous and NASA should follow quarantine procedures as outlined in previous NRC studies (NRC, 2002b). The committee also urges NASA to set an operational value for the life detection threshold limit through a separate advisory process drawing on a broad range of relevant expertise.

There has been some concern that if a sample return is required, the planning for the first human mission to Mars may be delayed until a sample can be obtained. The committee believes that, even should a sample be required because organic carbon has been found, a baseline mission plan for a mission to Mars and even hardware development may still proceed under the assumption that a sample return will not find anything significant enough with regard to Martian biology to invalidate the baseline mission plan.

To prevent contamination of Earth by Martian material, great care must be exercised to ensure the containment of all material returned from Mars to Earth. There must be a sterile, intermediate transfer conducted in space that ensures Earth’s environment will not be exposed to any Martian material, including dust or soil deposits on the outside surface of the return vehicle. The protocols for such a sterile transfer will be complex and, if the transfer is unsuccessful, may require that the return vehicle be discarded in space and never returned to Earth. Ultimately, however, only contained materials should be transported back to Earth, unless sterilized first (NRC, 1997).

Clark, B.C., A.K. Baird, R.J. Weldon, D.M. Tsuasaki, L. Schnabel, and M.P. Candelaria. 1982. “Chemical Composition of Martian Fines.” Journal of Geophysical Research 87:10059-10067.

Greeley, R., ed. 2001. Scientific Goals, Objectives, Investigations, and Priorities, Mars Exploration Program/Payload Analysis Group (MEPAG), March 2. Also known as Jet Propulsion Laboratory (JPL) Publication 01-7 (2001). JPL, Pasadena, Calif.

National Research Council (NRC). 1997. Mars Sample Return: Issues and Recommendations. National Academy Press, Washington, D.C.

NRC. 2002a. Assessment of Mars Science and Mission Priorities. National Academy Press, Washington, D.C.

NRC. 2002b. The Quarantine and Certification of Martian Samples. National Academy Press, Washington, D.C.

Wanke H., J. Bruckner, G. Dreibus, R. Rieder, and I. Ryabchikov. 2001. “Chemical Composition of Rocks and Soils at the Pathfinder Site.” Space Studies Review 96: 317-330.

A Report of the Solar and Space Physics Survey Committee

The Sun is the source of energy for life on Earth and is the strongest modulator of the human physical environment. In fact, the Sun’s influence extends throughout the solar system, both through photons, which provide heat, light, and ionization, and through the continuous outflow of a magnetized, supersonic ionized gas known as the solar wind. The realm of the solar wind, which includes the entire solar system, is called the heliosphere. In the broadest sense, the heliosphere is a vast interconnected system of fast-moving structures, streams, and shock waves that encounter a great variety of planetary and small-body surfaces, atmospheres, and magnetic fields. Somewhere far beyond the orbit of Pluto, the solar wind is finally stopped by its interaction with the interstellar medium, which produces a termination shock wave and, finally, the outer boundary of the heliosphere. This distant region is the final frontier of solar and space physics.

During the 1990s, space physicists peered inside the Sun with Doppler imaging techniques to obtain the first glimpses of mechanisms responsible for the solar magnetic dynamo. Further, they imaged the solar atmosphere from visible to x-ray wavelengths to expose dramatically the complex interaction between the ionized gas and the magnetic field, which drives both the solar wind and energetic solar events such as flares and coronal mass ejections that strongly affect Earth. An 8-year tour of Jupiter’s magnetosphere, combined with imaging from the Hubble Space Telescope, has revealed completely new phenomena resident in a regime dominated by planetary rotation, volcanic sources of charged particles, mysteriously pulsating x-ray auroras, and even an embedded satellite magnetosphere.

The response of Earth’s magnetosphere to variations in the solar wind was clearly revealed by an international flotilla of more than a dozen spacecraft and by the first neutral-atom and extreme-ultraviolet imaging of energetic particles and cold plasma. At the same time, computer models of the global dynamics of the magnetosphere and of the local microphysics of magnetic reconnection have reached a level of sophistication high enough to enable verifiable predictions.

While the accomplishments of the past decades have answered important questions about the physics of the Sun, the interplanetary medium, and the space environments of Earth and other solar system bodies, they have also highlighted other questions, some of which are long-standing and fundamental. This report organizes these questions in terms of five challenges that are expected to be the focus of scientific investigations during the coming decade and beyond:

• Challenge 1: Understanding the structure and dynamics of the Sun’s interior, the generation of solar magnetic fields, the origin of the solar cycle, the causes of solar activity, and the structure and dynamics of the corona. Why does solar activity vary in a regular 11-year cycle? Why is the solar corona several hundred times hotter than its underlying visible surface, and how is the supersonic solar wind produced?

• Challenge 2: Understanding heliospheric structure, the distribution of magnetic fields and matter throughout the solar system, and the interaction of the solar atmosphere with the local interstellar medium. What is the nature of the interstellar medium, and how does the heliosphere interact with it? How do energetic solar events propagate through the heliosphere?

• Challenge 3: Understanding the space environments of Earth and other solar system bodies and their dynamical response to external and internal influences. How does Earth’s global space environment respond to solar variations? What are the roles of planetary ionospheres, planetary rotation, and internal plasma sources in the transfer of energy among planetary ionospheres and magnetospheres and the solar wind?

• Challenge 4: Understanding the basic physical principles manifest in processes observed in solar and space plasmas. How is magnetic field energy converted to heat and particle kinetic energy in magnetic reconnection events?

• Challenge 5: Developing near-real-time predictive capability for understanding and quantifying the impact on human activities of dynamical processes at the Sun, in the interplanetary medium, and in Earth’s magnetosphere and ionosphere. What is the probability that specific types of space weather phenomena will occur over periods from hours to days?

An effective response to these challenges will require a carefully crafted program of space- and ground-based observations combined with, and guided by, comprehensive theory and modeling efforts. Success in this endeavor will depend on the ability to perform high-resolution imaging and in situ measurements of critical regions of the solar system. In addition to advanced scientific instrumentation, it will be necessary to have affordable constellations of spacecraft, advanced spacecraft power and propulsion systems, and advanced computational resources and techniques.

This report summarizes the state of knowledge about the total heliospheric system, poses key scientific questions for further research, and lays out an integrated research strategy, with prioritized initiatives, for the next decade. The recommended strategy embraces both basic research programs and targeted basic research activities that will enhance knowledge and prediction of space weather effects on Earth. The report emphasizes the importance of understanding the Sun, the heliosphere, and planetary magnetospheres and ionospheres as astrophysical objects and as laboratories for the investigation of fundamental plasma physics phenomena. The recommendations presented in the main report are listed also in this Executive Summary.

The integrated research strategy proposed by the Solar and Space Physics Survey Committee is based on recommendations from four technical study panels regarding research initiatives in the following subject areas: solar and heliospheric physics, solar wind-magnetosphere interactions, atmosphere-ionosphere-magnetosphere interactions, and theory, computation, and data exploration. Because it was charged with recommending a program that will be feasible and responsible within a realistic resource envelope, the committee could not adopt all of the panels’ recommendations. The committee’s final set of recommended initiatives thus represents a prioritized selection from a larger set of initiatives recommended by the study panels. (All of the panel recommendations can be found in the second volume of this report, The Sun to the Earth—and Beyond: Panel Reports, 2003, in press.)

The committee organized the initiatives that it considered into four categories: large programs, moderate programs, small programs, and vitality programs. Moderate and small programs comprise both space missions and ground-based facilities and are defined according to cost, with moderate programs falling in the range from $250 million to $400 million and small programs costing less than $250 million. The committee considered one large (>$400 million) program, a Solar Probe mission, and gave it high priority for implementation in the decade 2003-2013. The programs in the vitality category are those that relate to the infrastructure for solar and space physics research; they are regarded by the committee as essential for the health and vigor of the field. The cost estimates used by the committee for all four categories are based either on the total mission cost or, for level-of-effort programs, on the total cost for the decade 2003-2013. FY 2002 costs are used in each case.

In arriving at a final recommended set of initiatives, the committee prioritized the selected initiatives according to two criteria—scientific importance and societal benefit. The ranked initiatives are listed and described briefly in Table ES.1. As discussed in Chapter 2, the rankings in Table ES.1, cost estimates, and judgments of technical readiness were then used to arrive at an overall program that could be conducted in the next decade while remaining within a reasonable budget. Nearly all of the recommended missions and facilities either are already planned or were recommended in previous strategic planning exercises conducted by the National Aeronautics and Space Administration (NASA) and the National Science Foundation (NSF).

The committee’s recommended phasing of NASA missions and initiatives is shown in Figures ES.1 and ES.2; its recommended phasing of NSF initiatives is shown in Figure ES.3. While the committee did not find a need to create completely new mission or facility concepts, some existing programs are recommended for revitalization and will require stepwise or ramped funding increases. These programs include NASA’s Suborbital program, its

Supporting Research and Technology (SR&T) program, and the University-Class Explorer (UNEX) Program, as well as guest investigator initiatives for national facilities in the NSF. In the vitality category, new theory and modeling initiatives, notably the Coupling Complexity initiative (discussed in the report of the Panel on Theory, Modeling, and Data Exploration) and the Virtual Sun initiative (discussed in the report of the Panel on the Sun and Heliospheric Physics), are recommended.

The committee developed its national strategy based on a systems approach to understanding the physics of the coupled solar-heliospheric environment. The existence of ongoing NSF programs and facilities in solar and space physics, of two complementary mission lines in the NASA Sun-Earth Connection program—the Solar Terrestrial Probes (STP) for basic research and Living With a Star (LWS) for targeted basic research—and of applications and operations activities in the National Oceanic and Atmospheric Administration (NOAA) and the Department of Defense (DOD) facilitates such an approach.

As a key first element of its systems-oriented strategy, the committee endorsed three approved NASA missions: Solar-B and the Solar Terrestrial Relations Observatory (STEREO), both part of STP, and the Solar Dynamics Observatory (SDO), part of LWS. Together with ongoing NSF-supported solar physics programs and facilities as well as the start of the Advanced Technology Solar Telescope (ATST), these missions constitute a synergistic approach to the study of the inner heliosphere that will involve coordinated observations of the solar interior and atmosphere and the formation, release, evolution, and propagation of coronal mass ejections toward Earth. Later in the decade covered by the survey, overlapping investigations by the SDO (LWS), the ATST, and Magnetospheric Multiscale (MMS) (part of STP), together with the start

FIGURE ES.3 Recommended phasing of major new and enhanced NSF initiatives. The budget wedge for new facilities science refers to support for guest investigator and related programs that will maximize the science return of new ground facilities to the scientific community. Funding for new facilities science is budgeted at approximately 10 percent of the aggregate cost for new NSF facilities.

of the Frequency-Agile Solar Radiotelescope (FASR), will form the intellectual basis for a comprehensive study of magnetic reconnection in the dense plasma of the solar atmosphere and the tenuous plasmas of geospace.

The committee’s ranking of the Geospace Electrodynamic Connections (GEC; STP) and Geospace Network (LWS) missions acknowledges the importance of studying Earth’s ionosphere and inner magnetosphere as a coupled system. Together with a ramping up of the launch opportunities in the Suborbital Program and the implementation of both the Advanced Modular Incoherent Scatter Radar (AMISR) and the Small Instrument Distributed Ground-Based Network, these missions will provide a unique opportunity to study the local electrodynamics of the ionosphere down to altitudes where energy is transferred between the magnetosphere and the atmosphere, while simultaneously investigating the global dynamics of the ionosphere and radiation belts. The implementation of the L1 Monitor (NOAA) and of the vitality programs will be essential to the success of this systems approach to basic and targeted basic research. Later on in the committee’s recommended program, concurrent operations of a Multispacecraft Heliospheric Mission (MHM; LWS), Stereo Magnetospheric Imager (SMI; STP), and Magnetosphere Constellation (MagCon; STP) will provide opportunities for a coordinated approach to understanding the large-scale dynamics of the inner heliosphere and Earth’s magnetosphere (again with strong contributions from the ongoing and new NSF initiatives).

To understand the genesis of the heliospheric system it is necessary to determine the mechanisms by which the solar corona is heated and the solar wind is accelerated and to understand how the solar wind evolves in the innermost heliosphere. These objectives will be addressed by a Solar Probe mission. Because of the importance of these objectives for the overall understanding of the solar-heliosphere system, as well as of other stellar systems, a Solar Probe mission¹ should be implemented as soon as possible within the coming decade. The Solar Probe

measurements will be complemented by correlative observations from such initiatives as Solar Orbiter, SDO, ATST, and FASR.

Similarly, because of the importance of comparative magnetospheric studies for advancing the understanding basic magnetospheric processes, the committee has assigned high priority to a Jupiter Polar Mission (JPM), a space physics mission to study high-latitude electrodynamic coupling at Jupiter. Such a mission will provide both a means of testing and refining theoretical concepts developed largely in studies of the terrestrial magnetosphere and a means of studying in situ the electromagnetic redistribution of angular momentum in a rapidly rotating system, with results relevant to such astrophysical questions as the formation of protostars.

Technology development is required in several critical areas if a number of the future science objectives of solar and space physics are to be accomplished.

Traveling to the planets and beyond. New propulsion technologies are needed to rapidly propel spacecraft to the outer fringes of the solar system and into the local interstellar medium. Also needed are power systems to support future deep space missions.

Advanced spacecraft systems. Highly miniaturized spacecraft and advanced spacecraft subsystems will be critical for a number of high-priority future missions and programs in solar and space physics.

Advanced science instrumentation. Highly miniaturized sensors of charged and neutral particles and photons will be essential elements of instruments for new solar and space physics missions.

Gathering and assimilating data from multiple platforms. Future flight missions include multipoint measurements to resolve spatial and temporal scales that dominate the physical processes that operate in solar system plasmas.

Modeling the space environment. Primarily because of the lack of a sufficient number of measurements, it has not been necessary until quite recently for the solar and space physics community to address data assimilation

issues. However, it is anticipated that within 10 years vast arrays of data sets will be available for assimilation into models.

Observing geospace from Earth. The severe terrestrial environments of temperature, moisture, and wildly varying solar insolation have posed serious reliability problems for arrays of ground-based sensor systems that are critical for solar and space physics studies.

Observing the Sun at high resolution. Recent breakthroughs in adaptive optics have eliminated the major technical impediments to making solar observations with sufficient resolution to measure the pressure scale height, the photon mean free path, and the fundamental magnetic structure size.

The fully or partially ionized plasmas that are the central focus of solar and space physics are related on a fundamental level to laboratory plasma physics, which directly investigates basic plasma physical processes, and to astrophysics, a discipline that relies heavily on understanding the physics unique to the plasma state. Moreover, there are numerous points of contact between space physics and atmospheric science, particularly in the area of aeronomy. Knowledge of the properties of atoms and molecules is critical for understanding a number of magnetospheric, ionospheric, solar, and heliospheric processes. Understanding developed in one of these fields is thus in principle applicable to the others, and productive cross-fertilization between disciplines has occurred in a number of instances.

The space environment of the Sun-Earth system can have deleterious effects on numerous technologies that are used by modern-day society. Understanding this environment is essential for the successful design, implementation, and operation of these technologies.

National Space Weather Program. A number of activities are under way in the United States to better understand and mitigate the effects of solar activity and the space environment on important technological systems. The mid-1990s saw the creation of the National Space Weather Program (NSWP), an interagency program whose goal is “to achieve, within a ten year period, an active, synergistic, interagency system to provide timely, accurate,

and reliable space environment observations, specifications, and forecasts.”³ In 1999, NASA initiated an important complementary program, Living With a Star (LWS), which over the next decade and beyond will carry out targeted basic research on space weather. Crucial components of the national space weather effort continue to be provided by the operational programs of the Department of Defense and NOAA. Moreover, in addition to governmental activities, a number of private companies have, over the last decade, become involved in developing and providing space weather products.

Monitoring the solar-terrestrial environment. Numerous research instruments and observations are required to provide the basis for modeling interactions between the solar-terrestrial environment and technical systems and for making sound technical design decisions that take such interactions into account. Transitioning of programs and/or their acquisition platforms or instruments into operational use requires strong and effective coordination efforts among agencies. Imaging of the Sun and of geospace will play central roles in operational space forecasting in the future.

Transition from research to operations. Means must be established for transitioning new knowledge into those arenas where it is needed for design and operational purposes. Creative and cutting-edge research in modeling the solar-terrestrial environment is under way. Under the auspices of the NSWP, models that are thought to be potentially useful for space weather applications can be submitted to the Community Coordinated Modeling Center (currently located at the NASA Goddard Space Flight Center) for testing and validation. Following validation, the models can be turned over to either the U.S. Air Force or the NOAA Rapid Prototyping Center, where the models are used for the objectives of the individual agencies. In many instances, the validation of research products and models is different in the private and public sectors, with publicly funded research models and system-impact products usually being placed in an operational setting with only limited validation.

Data acquisition and availability. During the coming decade, gigabytes of data could be available every day for incorporation into physics-based data assimilation models of the solar-terrestrial environment and into system-impact codes for space weather forecasting and mitigation purposes. DOD generally uses data that it owns and only recently has begun to use data from other agencies and institutions, so that not many data sets are available for use by the publicly funded or commercial vendors who design products for DOD. Engineers typically are interested in

space climate, not space weather. Needed are long-term averages, the uncertainties in these averages, and values for the extremes in key space weather parameters. The engineering goal is to design systems that are as resistant as possible to the effects of space weather.

Public and private sectors in space weather applications. To date, the largest efforts to understand the solar-terrestrial environment and apply the knowledge for practical purposes have been mostly publicly funded and have involved government research organizations, universities, and some industries. Recently some private companies both large and small have been devoting their own resources to the development and sale of specialized products that address the design and operation of certain technical systems that can be affected by the solar-terrestrial environment. The private efforts often use publicly supported assets (such as spacecraft data) as well as proprietary instrumentation and models. A number of the private efforts use proprietary system knowledge to guide their choices of research directions. Policies on such matters as data rights, intellectual property rights and responsibilities, and benchmarking criteria can be quite different for private efforts and publicly supported ones, including those of universities. Thus, transitioning knowledge and models from one sector to another can be fraught with complications and requires continued attention and discussion by all interested entities.

The committee’s consideration of issues related to education and outreach was focused in two areas: ensuring a sufficient number of future scientists in solar and space physics and identifying ways in which the solar and space physics community can contribute to national initiatives in science and technology education.

Solar and space physics in colleges and universities. Because of its relatively short history, solar and space physics appears only adventitiously in formal instructional programs, and an appreciation of its importance is often lacking in current undergraduate curricula. If solar and space physics is to have a healthy presence in academia, additional faculty members would be needed to guide student research (both undergraduate and graduate), to teach SSP graduate programs, and to integrate topics in solar and space physics into basic physics and astronomy classes.

Distance education. Education in solar and space physics during the academic year could be considerably enhanced if the latest advances in information technology are exploited to provide distance learning for both graduate students and postdoctoral researchers. This approach would substantially increase the educational value of the expertise that currently resides at a limited number of institutions.

Undergraduate research opportunities and undergraduate instruction. NSF support for the Research Experiences for Undergraduates (REU) program has been valuable for encouraging undergraduates in the solar and space physics research area.

Advances in understanding in solar and space physics will require strengthening a number of the infrastructural aspects of the nation’s solar and space physics program. The committee has identified several that depend on effective program management and policy actions for their success: (1) development of a stronger research community, (2) cost-effective use of existing resources, (3) ensuring cost-effective and reliable access to space, (4) improving interagency cooperation and coordination, and (5) facilitating international partnerships.

Strengthening the solar and space physics research community. A diverse and high-quality community of research institutions has contributed to solar and space physics research over the years. The central role of the universities as research sites requires enhancement, strengthening, and stability.

Cost-effective use of existing resources. Optimal return in solar and space physics is obtained not only through the judicious funding and management of new assets, but also through the maintenance and upgrading, funding, and management of existing facilities.

Access to space. The continuing vitality of the nation’s space research program is strongly dependent on having cost-effective, reliable, and readily available access to space that meets the requirements of a broad spectrum of diverse missions. The solar and space physics research community is especially dependent on the availability of a wide range of suborbital and orbital flight capabilities to carry out cutting-edge science programs, to validate new instruments, and to train new scientists. Suborbital flight opportunities are very important for advancing many key aspects of future solar and space physics research objectives and for enabling the contributions that such opportunities make to education.

Low-cost launch vehicles with a wide spectrum of capabilities are critically important for the next generation of solar and space physics research, as delineated in this report.

• NASA should aggressively support the engineering research and development of a range of low-cost vehicles capable of launching payloads for scientific research.

• NASA should develop a memorandum of understanding with DOD that would delineate a formal procedure for identifying in advance flights of opportunity for civilian spacecraft as secondary payloads on certain Air Force missions.

• NASA should explore the feasibility of similar piggybacking on appropriate foreign scientific launches.

The comparative study of planetary ionospheres and magnetospheres is a central theme of solar and space physics research.

The principal investigator (PI) model that has been used for numerous Explorer missions has been highly successful. Strategic missions such as those under consideration for the STP and LWS programs can benefit from emulating some of the management approach and structure of the Explorer missions. The committee believes that the science objectives of the solar and space physics missions currently under consideration are best achieved through a PI mode of mission management.

Interagency cooperation and coordination. Interagency coordination over the years has yielded greater science returns than could be expected from single-agency activities. In the future, a research initiative at one agency could trigger a window of opportunity for a research initiative at another agency. Such an eventuality would leverage the resources contributed by each agency.

International partnerships. The geophysical sciences—in particular, solar and space physics—address questions of global scope and inevitably require international participation for their success. Collaborative research with other nations allows the United States to obtain data from other geographical regions that are necessary to determine the global distributions of space processes. Studies in space weather cannot be successful without strong participation from colleagues in other countries and their research capabilities and assets, in space and on the ground.

A Report of the Steering Committee on Space Applications and Commercialization

Earth science research has been significantly enhanced over the past several decades through the use of satellite remote sensing data. Advances in the spatial and spectral resolution of civil satellite data and the accumulation of these data over multiple time periods have made it possible for scientists to examine new types of research problems and environmental changes at both global and local scales. Although remote sensing data were initially obtained by scientists through satellites developed and launched by federal science agencies, the institutional landscape for the production of remote sensing data has become more diverse, with both government and the private sector actively involved in providing data for science. In addition, public-private partnerships have been established in which the government and the private sector collaborate to provide data for research; and, since the advent of operational sources of commercially produced data, remote sensing data for scientific research are also produced in the private sector itself. This diversification has been encouraged and fostered by the U.S. government through both congressional and executive branch action. Together, these forces have contributed to a changing environment for remote sensing and Earth science research.

The Steering Committee on Space Applications and Commercialization convened a workshop in March 2001 to explore the implications of the changing environment and the new relationships among researchers, government, and private sector remote sensing data providers. Its purpose was to examine such issues as scientific requirements for data obtained from the private sector, the distribution of scientific data obtained from private sector sources, continuity and permanent archiving of scientific data, data cost and access, and intellectual property considerations in the use of data obtained from the private sector (see Chapter 4). The steering committee oriented the workshop, entitled “Remote Sensing and Basic Research: The Changing Environment,“ to issues related to public and private sector relationships and interactions involving commercially provided remote-sensing data for scientific research. Attended by scientists, officials of federal science agencies, and representatives of the private sector, the workshop focused on the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and the National Aeronautics and Space Administration’s (NASA’s) Science Data Buy (SDB),¹ public-private sector interactions that have been functioning for several years in the United States.

This report draws heavily on information from a workshop planning meeting with agency sponsors, on information presented by workshop speakers and by participants in breakout group discussions, and on the expertise and viewpoints of the members of the Steering Committee on Space Applications and Commercialization. It addresses domestic and civil issues related to public-private sector partnerships for remote sensing data. The recommendations are the consensus of the steering committee and are not necessarily those of the workshop participants.

The primary focus of this report is on public-private sector relationships and interactions for the production and delivery of satellite remote sensing data for scientific research. Such relationships could include public-private partnerships; redistributor-end user relationships; and “anchor tenant” relationships, in which the public sector guarantees that it will be a customer of commercial remote sensing enterprises. The steering committee uses the generic term “public-private partnerships” to describe all of these relationships.

Government and the private sector have come together on several previous occasions to produce remote sensing data. The relationship between Radarsat 1 and Radarsat International in Canada is that of a joint public-private venture, as is the relationship between Système pour l’Observation de la Terre (SPOT) satellite and Spot Image company in France; and in the United States, the federal government privatized the Landsat remote sensing program through a commercial operator, Earth Observation Satellite Company (EOSAT), during the mid-1980s and

early 1990s. These arrangements were devised to make it possible to market the data commercially, and the more recent SeaWiFS and SDB programs provide remote sensing data to scientists.

The steering committee found significant differences in the operating practices and goals of the three groups— government, the private sector, and the scientific community—involved in public-private partnerships. Because the government is publicly accountable for all its actions, it must operate in a complex regulatory environment. Government agencies are also subject to the policy and fiscal priorities of both the White House and the U.S. Congress. (Although both of the public-private partnerships examined at the workshop were conducted by NASA, this report speaks of the government sector as a whole, since other government agencies may become involved in public-private partnerships for data in the future.) Private sector firms engaged in the development of satellites must recover their investment costs and make a profit, and, as a consequence, they must perceive a new public-private partnership to be financially viable before they will take part in it.

Government acquisition of scientific data for research through an agreement with the private sector involves more than a simple commercial transaction. The partnership of entities with such dissimilar modes of operating inevitably raises complex issues related to how the new organization should function. Differences between the government and the private sector complicate negotiations on intellectual property and licensing agreements related to the use of privately owned remote sensing data, on data management and data continuity, on the development of measures of performance for public-private partnerships, and on realistic cost accounting in these partnerships (see the section below, “General Conclusions and Priority Issues“). These complications are heightened when the partnership is created to serve the needs of a third group—in this case, scientists who have their own requirements. According to scientists at the workshop, having access to the high-resolution and other commercially produced remote sensing data available through public-private partnerships is extremely valuable and makes new types of research possible. However, scientists also value the free and open exchange of scientific data; the capacity to validate scientific results through reanalysis of the data; the calibration, validation, and verification of satellite data to ensure accuracy; long-term stewardship of data for future research; and continuity of the data over multiple points in time. The intersection of scientific and commercial interests in public-private partnerships can pose challenges to meeting these requirements.

It is not yet clear whether public-private partnerships will become the model for future institutions or are merely a temporary arrangement for obtaining data for research. It is clear, however, that existing public-private partnerships are valuable mechanisms for acquiring data that may not otherwise have been available to scientific researchers, that such partnerships have many advantages, and that they can be improved. Despite differences among the partners, clear benefits can be gained through their collaboration. The two public-private partnerships discussed at the workshop were instructive in terms of identifying both ways to meet the needs of commercial, government, and scientific participants in future partnerships and ways of improving how such partnerships function.

Finding. Full and open access² to data and the opportunity both to replicate research findings and to conduct further research using the same data are critical to scientific research. Because private sector firms view their data as intellectual property, there may be additional costs or intellectual property problems in reusing the data for scientific research. The steering committee found that the Science Data Buy was, in fact, a “science data license.” Rather than purchasing the data, the government obtained licenses or data property rights from those commercial companies that specified terms for use of the data. This raises intellectual property issues related to the subsequent redistribution and archiving of the data according to standard scientific practices.

Finding. Two public-private partnership programs for science data—Sea-viewing Wide Field-of-view Sensor and Science Data Buy—have been in operation for several years, and the initial phase of one of them, the SDB, has been completed. Formal program evaluation will help the government assess existing operations and understand how best to structure future programs.

Finding. All scientists at U.S. academic institutions should be able to compete for data from NASA’s Science Data Buy. Participation in the SDB is limited to current NASA grantees, but other academic scientists could usefully participate in the program.

Finding. Continuity of remote sensing observations over long periods of time is essential for Earth system science and global change research, and it requires that scientists have access to repeated observations obtained over periods of many years. Data obtained through public-private partnerships could continue to be useful as historical or “heritage” data. As scientists expand their use of data from both public and private sources, problems may arise in combining remote sensing data from multiple sensors with different capabilities and characteristics. Research on sensor intercomparisons is necessary to ensure that data from multiple sources can be exploited for future, time-series research. This approach is preferable to that of maintaining older technologies to assure continuity.

Finding. Scientific data obtained through public-private partnerships must be available for future use through data centers and permanent archives. Since the government obtains a license for scientists to use data under existing public-private partnerships rather than purchasing the data, there are intellectual property issues related to depositing these data in open scientific archives. Archives and data centers should include data and relevant metadata that are amenable to reprocessing after algorithms have been improved.

Finding. Scientists require instrument characterization and data calibration to physical units with quantified uncertainty. Access to calibrated data is an essential precondition for many scientific uses of remote sensing data, to ensure the quality of the data and to ensure that data sets differing in spatial, temporal, or spectral coverage, or acquired by different instruments, are comparable. In public-private partnerships, the government has often assumed responsibility for calibration, validation, and verification. The steering committee commends the govern

Finding. Consistent approaches to documentation and preparation of data for long-term archiving are key to effective data stewardship in public-private partnerships.

Finding. Communication among government data providers, commercial data providers, and scientists is vital to effective partnerships. The interests and needs of the scientific community can be best incorporated into a public-private sector relationship during the early planning stages of the partnership. More opportunities for formal and informal communication are needed at all stages, especially between scientists and private sector representatives.

Finding. Public-private partnerships benefit from ongoing assessment, not just from retrospective evaluation. Performance measures should be tailored to the goals of the parties—that is, return on investment for industry, good science output for researchers, and cost-effective performance by government agencies.

Finding. Obtaining scientific data through a public-private partnership can involve significant nontransaction costs, such as support for data dissemination and for validation and verification on the government side and the expense of contract changes and delays on the private sector side. These buried costs may serve as a disincentive to future public-private partnerships.

The steering committee found that several issues must be addressed in creating future public-private partnerships that produce remote sensing data for scientific research. Many of these issues are referred to in the findings and recommendations outlined above (licensing, data continuity, performance measures, and realistic cost accounting), while others such as the impact of government processes on public-private partnerships (e.g., contracting

arrangements), intellectual property rights, and data management are discussed in the body of the report (see Chapter 4).

The steering committee prioritized these issues according to their significance for public-private partnerships and the degree of complexity and difficulty expected to be involved in resolving them (see Table ES.1).

The most significant and complex issues to be addressed for public-private partnerships are those related to intellectual property and licensing and to government processes. Little convergence exists between the public and private sectors on these topics, and yet future actions will have significant impact on the use of commercial remote sensing data for scientific research. Data management (e.g., data archiving and processing) and data continuity are rated by the steering committee as highly significant but of lesser complexity, because they can be addressed readily if financial resources are available. Measures of performance (metrics) for public-private partnerships were deemed highly complex, owing to the difficulty in determining performance measures, but of lesser significance than other issues involved in establishing successful public-private partnerships for providing remote sensing data for scientific research. The steering committee considered realistic cost accounting critical for creating future, successful partnerships, but of lower significance and complexity than other issues it analyzes in the report.

A Report of the Steering Committee on Space Applications and Commercialization

The past decade has seen significant improvement in the spatial and spectral resolution of the civil remote sensing data available to state, local, and regional governments. With the development of advanced airborne remote sensing technologies like lidar (light detection and ranging) and the launch of high-resolution, commercial remote sensing satellites, state and local jurisdictions now have the opportunity to obtain digital data at resolutions approaching those of aerial photography. State and local users of remote sensing data can also access data from the Landsat series for comparisons and detection of change over decades.

As important as these improvements in the quality and availability of remote sensing data is the growing number of geospatial data management and analysis tools available for use by state and local governments. With geographic information systems (GIS), digital remote sensing data can now be integrated with other types of digital data currently managed by state and local governments. Such technological advances can foster the development of remote sensing applications in the nonfederal public sector.

However, the use of remote sensing data and applications involves more than the underlying technical capacity. From the perspective of the remote sensing applications end user in state, local, or regional government, what is important is the information that remote sensing applications can make available, not the raw data per se. Equally important, the ability of a state or local government agency or jurisdiction to take advantage of recent technological advances depends on institutional, leadership, budgetary, procedural, and even personnel factors.

To examine the full range of factors that have led to the development of successful applications of remote sensing data in state and local governments and to identify common problems encountered in this process, the Space Studies Board’s Steering Committee on Space Applications and Commercialization organized the workshop “Facilitating Public Sector Uses of Remote Sensing Data.“ Presentations at the workshop included case studies of the adoption and use of remote sensing applications in local government (Baltimore, Maryland; Richland County, South Carolina; and Boulder County, Colorado), state government (Missouri, Washington, and North Carolina), and regional government (the Portland metropolitan area in Oregon and the communities of the Red River Valley along the North Dakota–Minnesota boundary); information on remote sensing applications in specific sectors and on patterns of adoption; and technical material on sensors. The workshop was attended by representatives of state, local, and regional governments, the federal government, the private sector, and universities.

The case studies illustrate some, not all, of the uses of remote sensing data in state and local government. The issues they raise are not specific to any single type of data or application. At the same time, certain uses of remote sensing data, especially in operational applications, may involve challenges and issues that are not directly addressed in this report.

This report draws on the information presented in the workshop, the workshop planning meeting with agency sponsors, and the expertise and viewpoints of the steering committee. For this reason, technical information is kept to a minimum. The report and its recommendations are the consensus of the steering committee and not necessarily of the workshop participants. The report is directed to those in state, local, and regional governments who make crucial decisions about both the commitment of resources to developing remote sensing capabilities and the use of remote sensing information in the public sector. The steering committee envisions that the report will also be useful to geospatial professionals in state, local, and regional government who work with those managers and decision makers; to remote sensing data providers in the federal government and the private sector; and to federal officials who interact with the nonfederal public sector on issues that require geospatial data.

The steering committee found that the context for the use of remote sensing applications in state, local, and regional governments differs significantly from that for other applications. Responsible primarily for providing public services and governance, state and local governments are supported by tax revenues that can vary considerably from year to year, and political considerations can also influence decision making. Many workshop participants spoke of budget shortfalls and stringencies they were experiencing or expected to experience in the next several years that could negatively influence the adoption and use of remote sensing data and information.

From the perspective of a commercial firm seeking to supply remote sensing data or services, the scale of the public sector can pose serious problems. The sheer number of state, local, and regional governments increases the costs of providing them with remote sensing data. There are 50 states and more than 3,100 counties in the United States; the New York City metropolitan area alone contains 31 counties and over 1,600 jurisdictions. In addition, nonfederal government decision making about new technologies is complicated and often requires buy-in from multiple parts of the government. Even if there were some timely way to determine which jurisdictions were prepared to buy remote sensing data or services, negotiating separate small contracts might not be cost-effective for large, commercial remote sensing firms.

From the perspective of state and local governments, moreover, there are benefits of working with local firms and universities rather than with data or other service providers from outside the immediate region. Proximity has always been a factor for governments working with small aerial photography firms, for example, and local firms establish long-term relationships with local government agencies.

The steering committee found that adoption of remote sensing data and information products in the nonfederal public sector has been affected by several aspects of policy and operations. These include (1) financial and budgetary constraints; (2) institutional, organizational, and political issues; (3) the geospatial experience, skills, and training available in the jurisdiction; (4) the capacity to make the transition from photographic to digital data; and (5) licensing and data management. The steering committee also found that the adoption of remote sensing data and applications is often related to having a strong advocate for the new technology who can persuade technical personnel, managers, decision makers, and even the public about the utility of the data and information.

It is advantageous for public sector jurisdictions considering the use of new remote sensing technologies to learn from the organizational practices of governments that have already used remote sensing applications successfully.

Finding: Some state and local governments have taken an ad hoc, decentralized approach to using remote sensing data. Individual departments or offices took it upon themselves to obtain the remote sensing data they needed for a specific application or project. Where there was no city- or statewide inventory of data, the independent purchases of data resulted in multiple acquisitions of the same remote sensing images and inefficient management and use of geospatial data resources. Certain municipal governments, however, took a more centralized approach, locating remote sensing resources within geospatial data or information offices under the direction of technical staff proficient in the use of geospatial data.

Budgetary and staffing limitations, coupled with the increased convergence of digital technologies, including geospatial data from GIS, satellite, and airborne remote sensing and even global positioning systems, suggest that an approach in which a single administrative entity manages geospatial data is more cost-effective than a decentralized approach and facilitates use of the data by state and local governments.

Finding: The cost of obtaining and managing remote sensing data can be prohibitive for state, local, and regional government departments or agencies, particularly during a period of budgetary shortfalls. The steering committee found that some governments in the nonfederal public sector have successfully joined together to form local or regional cooperatives or consortia that purchase remote sensing data for all members of the group. Data cooperatives can also help small jurisdictions to manage remote sensing and other digital data.

Finding: Public sector procurement processes for the purchase of remote sensing data can be lengthy and time-consuming, making it difficult for a jurisdiction to obtain timely authorization for purchasing such data. In addition, public sector accounting processes are most effective in dealing with marginal changes in budgets that are relatively constant from year to year. Remote sensing data may constitute a major purchase needed on an irregular basis, which can be difficult to accommodate in normal public sector accounting practices.

An independent body such as the Government Accounting Standards Board—a private, nonprofit institution that develops accounting reporting standards for state, local, county, and other nonfederal government entities—or another independent accounting organization could be consulted for input on how to account more effectively for expenditures on remote sensing data.

A large and active public sector market for remote sensing data and information will provide economies of scale for governments seeking cost-effective remote sensing applications and for the public, private, and international vendors that supply data and services to state and local governments (see “Working with the Private Sector,” in Chapter 4). The steering committee learned several ways in which a more active and effective market for state and local applications of remote sensing data and information can be created.

Finding: The increasing use of digital remote sensing data rather than photographic data by state and local governments means that new standards are needed for digital spatial data and information. The advantages of commonly accepted digital spatial data standards include reduced cost, improved ability to use the data for multiple purposes, standardization of technical training, and quality assurance. The adoption of digital data standards would require that procurement regulations for many state and local government entities be revised. Common standards for digital data could be developed by a coordinating body funded by the federal government that includes representatives of both data users and data providers. The federal agencies involved in the effort could determine which agency should take the lead.

Finding: Although commercial providers of remote sensing data recognize the potential economic significance of the nonfederal public sector market for remote sensing data, they often do not do enough to stimulate its development and growth.

Finding: The licensing provisions of commercial satellite data companies seem restrictive, offering little flexibility to state and local governments. Strictly followed, commercial licensing provisions can add to the cost of data in the nonfederal public sector and can result in redundant purchases of the same data within a single jurisdiction, creating a disincentive for state, local, and regional governments to purchase data from the private sector. Although representatives of private remote sensing firms suggested that it is possible to negotiate new licensing agreements based on specific needs, officials in the nonfederal public sector reported that they had not been made aware of this flexibility.

Finding: There is no single source of information on prospective remote sensing data needs of state, local, and regional governments. This limits the market to local firms or those that have personal contacts with a jurisdiction seeking bids for data or services. The failure to notify a larger potential contractor community may stifle competition and result in higher costs.

Finding: The steering committee found widespread cooperation between federal agencies and state, local, and regional governments in initiating remote sensing applications programs. Much of this cooperation, however, took place within federal programs that support state and local government use of remote sensing data for specific programmatic objectives. Some state and local government representatives are seeking general infrastructure, support, or guidance on how they might take advantage of remote sensing data or applications programs supported by the federal government. There appears to be an unfulfilled need for a point of contact at federal agencies to help state and local users obtain information and facilitate collaboration between state and local users and federal agencies.