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5 Con,gressional Testimony 5.l Exploration of the Solar System in the Coming Decade Statement of Michael J.S. Belton, chair of the Solar System Exploration (DecadalJ Survey and President of Belton Space Exploration Initiatives, LLC, before the Subcommittee on Science, Technology, and Space, Committee on Commerce, Science, and Transportation, U.S. Senate, on July 30, 2003. Good afternoon, Mr. Chairman and members of the Committee. My name is Michael Belton, and I served as Chairman of the Solar System Exploration (Decadal) Survey for the Space Studies Board of the National Research Council. The NRC is the operating arm of the National Academy of Sciences, chartered by Congress in 1863 to advise the government on matters of science and technology. I am also an Emeritus Astronomer at the National Optical Astronomy Observatory and President of Belton Space Exploration Initiatives, LLC, in Tucson, Arizona. I have been involved in space exploration for most of my professional life and have been an investigator on several NASA flight missions including Mariner Venus-Mercury, Voyager, Galileo, Contour, and Deep Impact. The Office of Space Science of the National Aeronautics and Space Administration sponsored the SSE Survey to chart a bold strategy for general solar system and Mars exploration over the next decade. The Survey, which reported in July 2002, derived its recommendations and priorities by looking even farther into the future and is based on direct and well-considered inputs from the scientific community and interested public organizations. It has achieved a broad consensus of opinion in these communities. Its recommendations are for a strong, competi- tive, flight program based on a few key scientific questions, a sound research infrastructure including public outreach, and a forward-looking technology program that I expect will obtain the most innovative and cost-effective mission solutions. A critical element of the charge to the Survey was to formulate a "big picture" of solar exploration what it is, how it fits into other scientific endeavors, and why it is a compelling goal today. We were also tasked to develop an inventory of top-level scientific questions and provide a prioritized list of the most promising avenues for flight investigations and supporting ground-based activities for the period 2003-2013. In performing the Survey we took care to trace the relationships between basic motivational questions of interest to the public at large and the scientific objectives, integrating themes, key scientific questions, and prioritized mission list that form the core of our recommendations. Solar system exploration remains a compelling activity because 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? Mars and icy satellite explorations may soon provide an answer to the first question; exploration of comets, primitive asteroids, and Kuiper Belt objects may have much to say about the second; surveys of near-Earth objects will say something about the third. 99

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100 Space Studies Board Annual Report 2003 Although the scientific goals of NASA's Solar System Exploration program have been quite stable, in recent years the emphasis has increased in two areas the search for the existence of life, either past or extant, beyond Earth, and the development of detailed knowledge of the near-Earth environment in order to understand what potential hazards to the Earth may exist. The field of astrobiology has become an important element in solar system exploration and there is an increasing interest in learning more about objects that could collide with the Earth at some future time. The Survey developed four integrating themes to guide solar system exploration in the coming decade: The First Billion Years of Solar System History. This formative period propelled the evolution of Earth and the other planets, including the emergence of life on Earth, yet this epoch in our solar system's history is poorly known. Volatiles and Organics: The Stuff of Life. Life requires organic materials and volatiles, notably liquid water, originally condensed from the solar nebula and later delivered to the planets by organic-rich cometary and asteroidal debris. The Origin and Evolution of Habitable Worlds. Our concept of the "habitable zone" is being expanded by recent discoveries on Earth and elsewhere in the solar system. Understanding our planetary neighborhood will help to trace the evolutionary paths of the planets and the fate of our own. Processes: How Planets Work. Understanding the operation of fundamental processes is the find foundation of planetary science, providing insight to the evolution of worlds within our solar system, and planets around other stars. With these four themes agreed to, the Survey was able to prioritize among the literally hundreds of scientific questions of interest to the community. The resulting set of twelve key questions with high scientific merit should guide the selection of flight missions over the next decade. We measure the scientific merit of a question by asking whether its answer has the possibility of creating or changing a paradigm, whether the new knowledge might have a pivotal effect on the direction of future research, and to what degree the knowledge that might be gained would substantially strengthen the factual basis of our understanding. The twelve key questions, grouped within the four themes, are: The First Billion Years of Solar System History 1. What processes marked the initial stages of planet and satellite formation? 2. How long did it take the gas giant Jupiter to form, and how was the formation of the ice giants different from that of the gas giants? 3. What was the rate of decrease in the impactor flux throughout the solar system, and how did it affect the timing of the emergence of life? Volatiles and Organics: The Stuff of Life 4. What is the history of volatile material, especially water, in our solar system? 5. What is the nature and history of organic material in our solar system? 6. What planetary processes affect the evolution of volatiles on planetary bodies? The Origin and Evolution of Habitable Worlds 7. Where are the habitable zones for life in our solar system, and what are the planetary processes responsible for producing and sustaining habitable worlds? 8. Does (or did) life exist beyond the Earth? 9. Why did the terrestrial planets diverge so dramatically in their evolution? 10. What hazards do solar system objects present to Earth's biosphere? Processes: How Planets Work 11. How do the processes that shape the contemporary character of planetary bodies operate and interact? 12. What does our solar system tell us about other solar systems, and vice versa?

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Congressional Testimony 101 To advance the subject these scientific themes and key questions must be addressed by a series of spaceflights of different sizes and complexities. Also, as resources are finite, these proposed new flight missions must be prioritized. It is important at this juncture to understand that the foundation on which the Survey's priorities rest must also be maintained and secured. The top-level programmatic priorities that are required to provide the foundation for productivity and continued excellence in solar system exploration are: Continue approved Solar System Exploration programs, such as the Cassini-Huygens mission to Saturn and Titan, those in the Mars Exploration Program, the Discovery Program of low-cost missions, and ensure a level of funding that is adequate for both the successful operations and the analysis of the data and publication of the results of these missions. Assure adequate funding for fundamental research programs, follow-on data analysis programs, and technology development programs that support these missions. Continue to support and upgrade the technical expertise and infrastructure in implementing organizations that provide vital services to enable and support solar system exploration missions. i;, i;, Continue to encourage, facilitate, and support international cooperation in its solar system exploration flight programs. Maintaining a mix of mission size is also important. For example, many aspects of the key science questions can be met through Discovery class missions (<$325 million), while other high-priority science issues will require larger, more expensive projects. Particularly critical in our strategy is the New Frontiers line of missions ($325 million to $650 million), which are principal-investigator (PI)-led, medium-class, competed missions. This line was proposed in the President's FY 2003 budget submission before the Survey was completed. The Survey strongly supported the proposal to establish a New Frontiers line of competitively procured flight missions with a total mission cost of approximately twice the Discovery cap. Experience has also shown that large missions that enable extended and scientifically multifaceted experimen- tation are an essential element of the mission mix. The Survey recommended that the development and implemen- tation of Flagship (>$650 million) missions, comparable to Viking, Voyager, Galileo, and Cassini-Huygens, be at a rate of about one per decade to provide for the comprehensive exploration of science targets of extraordinarily high priority. Within this structure the Survey recommended the following prioritized flight program of missions in general solar system exploration in the period 2003-2013. It must be emphasized that, at NASA's request, the prioritization was done within cost classes and not over the entire list. Also by NASA's request, the priorities for the Mars Exploration Program were kept separate from the priorities for the Solar System Exploration Division. Small Class 1. Discovery missions (at a frequency of approximately 1 every 18 months) 2. Cassini Extended Mission Medium Class Kuiper BeltIPluto 2. South Pole Aitkin Basin Sample Return 3. Jupiter Polar Orbiter with Probes 4. Venus In-situ Explorer 5. Comet Surface Sample Return Large Class (at afrequency of approximately I every decade) Europa Geophysical Explorer

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102 Space Studies Board Annual Report 2003 For the Mars Exploration Program the Survey recommended that in the coming decade the flight program should focus on missions that get down onto the surface of the planet with the ultimate goal of implementing Mars Sample Return missions in the period immediately following the current decade. It is believed that such samples are necessary to settle the question of the presence of life. The Survey recommended the following flight mission priorities for Mars exploration in the period 2006-2013: Small Class Mars Scout line 2. Mars Upper Atmosphere Orbiter Medium Class 1. Mars Smart Lander 2. Mars Long-lived Lander Network Large Class Mars Sample Return (Preparation for flight missions in the next decade) In addition the Survey committee counseled that NASA should seek to engage international partners at an early stage in the planning and implementation of Mars Sample Return; that the Mars Smart Lander (MSL), while addressing high-priority science goals, should take advantage of the opportunity to validate technologies required for sample return, and that the Scout program should be structured like the Discovery program, with PI leadership and competitive missions. The Survey advocated that a Scout mission should be flown at every other Mars launch opportunity. This future program for solar system exploration laid out above clearly requires a mix of medium and large- class missions to adequately challenge current scientific paradigms. It also requires that small missions whether Discovery class, Mars Scout, or mission extensions, provide focused ways of responding quickly to discoveries made or provide vehicles for entrepreneurial creativity and new scientific ideas. Our proposed Kuiper Belt-Pluto mission may well be the last great reconnaissance mission within solar system exploration and, with it completed, we can expect that the program will rapidly enter a phase of large and medium class missions operating on the surfaces of planets or within their atmospheres and plasma environments. These missions will utilize technologies, yet to be practically developed, that will enable long sojourns, power advanced instrumentation, and return samples to the Earth. The inclusion of Project Prometheus and the optical communications initiative in the President's FY 2004 budget submission are two excellent examples of the type of technology development that is needed to move solar system exploration forward. The Survey recognized that a significant investment in advanced technology development is needed in order for both the recommended flight missions to succeed and to provide a basis for increased science return from future missions. The following list of future possible missions (unprioritized) with high science value was noted by the Survey and gives some idea of the technical challenges that lie ahead: Terrestrial Planet Geophysical Network Asteroid Rover/Sample Return Ganymede Observer Titan Explorer Neptune Orbiter/Triton Explorer Saturn Ring Observer Mercury Sample Return Trojan/Centaur Reconnaissance Flyby lo Observer Europa Lander Neptune Orbiter with Probes Uranus Orbiter with Probes Venus Sample Return Comet Cryogenic Sample Return

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Congressional Testimony The Survey identified the following areas in which we believe that technology development is appropriate: Power: Advanced RTGs and in-space nuclear fission reactor power source Propulsion: Nuclear electric propulsion, advanced ion engines, aerocapture Communication: Ka band, large antenna arrays, and optical communication Architecture: Autonomy, adaptability, lower mass, lower power Avionics: Advanced packaging and miniaturization, standard operating system Instrumentation: Miniaturization, environmental (temperature, pressure, radiation) tolerance Entry to Landing: Autonomous entry, hazard avoidance, precision landing In-Situ Ops: Sample gathering, handling and analysis, drilling, instrumentation Mobility: Surface, aerial, subsurface, autonomy, hard-to-reach access Contamination: Forward contamination avoidance Earth Return: Ascent vehicles, in space rendezvous, and Earth return systems 103 These technology areas were not prioritized by the Survey. Nevertheless, I note that in-flight power and nuclear electric propulsion initiatives were included in the 2003 budget request and appear again in the 2004 request as Project Prometheus. Also, there are other elements of the above list that are, I believe, being actively considered for inclusion in a future mission in NASA's New Millennium program. The road that leads to the future of any endeavor is usually well defined only at its start. And quickly, the future becomes obscured by latent uncertainties: the possibility of new discoveries, of changing paradigms, changes in national policy, blind alleys, and funding pleasures and disappointments. Solar system exploration is no exception and in the time since the Survey was completed and published I have felt great excitement and considerable pleasure as important elements of our strategic plan have been proposed to Congress and move, hopefully, towards reality. The New Horizons mission, which I believe can fulfill our goals at the Kuiper Belt and Pluto, is seeing strong support the proposed Jupiter Icy Moons Mission will more than fulfill our goal of a flagship mission to further explore the subsurface oceans on Europa while simultaneously applying the new technologies that the Survey advocates as a basis for much of the future program. The most important of these new technologies in-flight power and nuclear electric propulsion are adequately covered in the proposed Project Prometheus. The New Frontiers program is going ahead and we await details of how NASA intends to implement this program to include the flight priorities that we have advocated. Finally, the research infrastructure, which underlies the flight program, also appears to be drawing adequate support. The tragic Columbia accident will no doubt have effects on this program in ways that I cannot anticipate. Whether these effects will be positive or negative remains to be seen. However, I note the old proverb "much good can often come out of adversity." Since the end of the Apollo Program, the human spaceflight program has served to enable a number of robotic missions (the Shuttle has been needed to launch important spacecraft such as the Ulysses, Magellan, and Galileo probes, and the Hubble Space Telescope), but has not played a direct role in the exploration of other solar system bodies. In the distant future I expect that this may change in some elements of the program. Human exploration of Mars is a long spoken of goal but faces major technical challenges. A second area is the protection of the Earth from a potentially hazardous near-Earth object on a collision course The role of . humans, if any, in such an endeavor has not yet been satisfactorily worked out and, in my opinion, deserves attention. In conclusion, the future of solar system exploration appears to be very bright. NASA is taking the technological and programmatic steps necessary to support future missions that will explore our solar system in astounding detail. Supported by the strategy laid out in the Survey, future solar system exploration will enable us to answer three fundamental human questions: Are we alone? Where did we come from? What is our destiny?

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104 Space Studies Board Annual Report 2003 5.2 Solar and Space Physics Research: The Coming Decade Statement of Louis J. Lanzerotti, Chair of the Solar and Space Physics Survey Committee and Consultant, Lucent Technologies, before the Subcommittee on Science, Technology and Space, Committee on Commerce, Science, and Transportation, U.S. Senate, on July 30, 2003. Good afternoon, Mr. Chairman and members of the committee. My name is Louis Lanzerotti, and I served as chairperson of the Solar and Space Physics Decadal Survey for the Space Studies Board of the National Research Council. The NRC is the operating arm of the National Academies, initially chartered by Congress in 1863 to advise the government on matters of science and technology. I am also Distinguished Research Professor at the New Jersey Institute of Technology and a consulting physicist at Bell Laboratories, Lucent Technologies. I am here today to provide an overview of the future of solar and space physics during the coming decade. I would like to begin by giving you some context for this area of science. The Sun is a variable, magnetic star. Solar and space physics research focuses on understanding the activity of our Sun and its effects on the Earth and the other planets. It also seeks to understand the physical processes that take place in the area in space around planets, including Earth. These planetary space environments are regions of ionized gas (or plasma) whose motions are subject to the influence of magnetic and electric fields. Solar and space physics seeks finally to explore and understand the interaction of the Sun with our galactic environment; that is, with the gas and dust between our solar system and nearby stars. Within this interstellar cloud, the solar wind, a continuous supersonic outflow of magnetized plasma from the Sun, not only interacts with the Earth and planets, but also inflates an enormous bubble, the heliosphere, whose boundaries lie far beyond the orbit of Pluto and have yet to be explored. It is the entire heliosphere that is the domain of solar and space physics. The knowledge that space physicists gain through their study of the Sun and solar system plasmas are very often applicable to the study of distant stars and galaxies and are related to laboratory plasma research. And, very importantly, in the particular case of the interactions of solar emissions with the Earth, this research has consider- able practical importance for technological systems and for humans in space. The explosive release of energy from the Sun solar storms produces a variety of disturbances in the Earth's space environment. These disturbances, known as 'Space weather," can adversely affect critical space-based and ground-based technologies and pose potential health hazards to astronauts and to the crews and passengers of aircraft flying polar routes. Understanding solar activity and its effect on the Earth's space environment is key to developing the means of understanding and ultimately mitigating the adverse effects of space weather. Recognition of the importance of achieving this understanding led to the establishment during the past decade of NASA's Living With a Star Program and the NSF-led interagency National Space Weather Program. Another area in which solar and space physics makes important contributions of practical value is the study of global climate change. Knowledge of both long- and short-term variations in the Sun's activity and output is critical to distinguish between natural variability in the Earth's climate and changes that result from human activity. That, in brief, is the scope and content of the field of solar and space physics. Since the space age began over 40 years ago, we have learned much about the workings of the Sun and the space environments of Earth and the other planets. But there are many questions still to be answered. In late 2000 the National Aeronautics and Space Administration (NASA), the National Science Foundation (NSF), the National Oceanic and Atmospheric Adminis- tration (NOAA), the Office of Naval Research, and the Air Force Office of Scientific Research asked the NRC to conduct a comprehensive study of the current status and future directions of U.S. ground- and space-based solar and space physics research programs. To carry out this task, a Survey Committee and five specialized study panels were established. The findings of the study panels were presented to the Survey Committee, which prepared a summary report based on the recommendations of the panels as well as on its own deliberations. Throughout the study process, the study panels and Survey Committee actively sought a broad community consensus with input from the wider solar and space physics community. The Survey Committee's report, The Sun to the Earth and Beyond: A Decadal Research Strategy in Solarand Space Physics, identifies five broad scientific challenges that define the focus and thrust of solar and space physics research in the decade 2003 through 2013. Further, the report develops specific program priorities that will be needed for the four sponsoring federal agencies, NASA, NSF, NOAA, and DOD, to meet these challenges. The Sun to the Earth and Beyond also identifies key technologies that must be developed to meet the immediate and projected requirements of solar and space physics research and presents policy recommendations designed to

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Congressional Testimony 105 strengthen the solar and space physics research enterprise. Throughout its deliberations, the Survey Committee paid particular attention to the applied aspects of solar and space physics to the important role that these fields play in a society whose increasing dependence on space-based technologies renders it ever more vulnerable to space weather. To address the five scientific challenges set forth in The Sun to the Earth and Beyond, the Survey Committee devised an integrated and prioritized set of research initiatives to be implemented in the 2003-2013 time frame. Nearly all of these initiatives are either planned or have been recommended in previous NASA and NSF planning efforts. The recommended initiatives fall within four categories: small programs (<$250 million); moderate programs ($250 million to $400 million); one large program costing (>$400 million); and "vitality" programs that focus on the infrastructure for solar and space physics research. To arrive at the final recommended set of initiatives, the Committee relied on two criteria scientific importance and societal benefit. Based on these criteria, the Committee assigned priorities to the recommended initiatives. A complete listing of the Survey Committee's prioritized recommendations, along with a thumbnail description of each program, is given in Table ES. 1 of the Executive Summary of the report. Instead of going through the entire list with you, it would be more instructive, I think, for me to outline the five science challenges identified by the Committee and to indicate the role that the four or five highest-priority initiatives will play in addressing those challenges during the coming decade. Challenge 1: Understanding the structure and dynamics of the Sun. During the past decade, thanks to several space missions and new ground-based observations, we have achieved notable advances in our knowledge and understanding of the structure and workings of the Sun's interior and the structure and dynamics of the million- degree solar atmosphere, the corona. However, answers to certain fundamental questions continue to elude us. Why, for example, is the Sun's corona several hundred times hotter than the Sun's surface? How is the solar wind, which expands from the corona, accelerated to the supersonic velocity that is measured in the solar system? How is the very intense magnetic energy that is stored in the Sun released both gradually and explosively? What is origin of the variability ("turbulence") observed in the solar wind and that affects Earth? To answer these questions, the Survey Committee strongly recommends implementation of a NASA Solar Probe mission to undertake the first exploration of the regions very near the Sun, which is the birthplace of the heliosphere itself. Measurements made close to the Sun by a Solar Probe will revolutionize our basic understanding of the solar wind. In addition, the Committee gave strong endorsement to the development of an advanced ground-based radio telescope (funded by NSF), the Frequency-Agile Solar Radiotelescope, that will provide a revolutionary new tool to study explosive energy release, three-dimensional structure, and magnetic fields in the corona. Challenge 2: Understanding heliospheric structure and the interaction of the solar wind with the local interstellar medium. We have acquired a great deal of new knowledge during the last ten years about the inner heliosphere (within the distance of Jupiter's orbit) and its changes over the course of a solar cycle most of our data have come from the joint NASA/European Space Agency Ulysses mission, which has provided single-point measurements over the poles of the Sun, i.e., out of the plane of the planets. The Survey Committee now recommends the implementation of a Multispacecraft Heliospheric Mission that would place four or more spacecraft in orbit about the Sun at different distances and solar longitudes to monitor changes across its entire globe. This mission will provide insight into the connections between solar activity, heliospheric disturbances, and the effects of the solar wind on Earth. This mission will thus represent an important addition to our national space weather effort. As I noted earlier in my statement, the solar wind inflates a giant bubble known as the heliosphere within the local interstellar medium. The outer reaches of the heliosphere and its boundary with the interstellar medium are among the last unexplored regions of the solar system. An Interstellar Probe that could directly sample these regions and move beyond the heliosphere to measure the material in the Sun's galactic environment has long been a dream of the space science community and would be one of the grand scientific enterprises of the early 21st century. Implementing such a mission exceeds our present technological capacity, however, particularly with respect to propulsion and power. The development of nuclear power capabilities in the next decade, as is presently planned by NASA, or the development of solar sails, would greatly facilitate an interstellar probe mission in the future. Challenge 3: U/zderstandi/zg the behavior of the space enviro/zme/zts of Earth and other solar system bodies. Earth's space environment draws energy from its interaction with the supersonic solar wind. This interaction drives the flow of plasma within the magnetosphere the volume of space controlled by Earth's magnetic field and leads to the storage and subsequent explosive release of magnetic energy in disturbances known as geomagnetic storms.

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106 Space Studies Board Annual Report 2003 (The northern and southern auroras are dramatic manifestations of this convulsive energy release.) The transfer of energy from the solar wind to the magnetosphere results from enisc~dic merging calf Earth's ~ec~ma~netic field with the portion of the Sun's magnetic field that is swept along with the solar wind. This process is known as magnetic reconnection. While the general role of this energy transfer in affecting the Earth's space environment has long been recognized, there are numerous unanswered fundamental questions. Therefore the Survey Committee endorsed as its highest priority in the moderate program category the NASA Magnetospheric Multiscale (MMS) mission, a four-spacecraft Solar Terrestrial Probe mission that is designed to study magnetic reconnection inside the magnetosphere and at its boundaries. Some of the energy extracted from the solar wind is deposited in Earth's high-latitude upper atmosphere, thus creating the aurora. To study the effects of magnetosphere disturbances on the structure and dynamics of the upper atmosphere, the Committee has assigned high priority in the small program category to the NSF's Advanced Modular Incoherent Scatter Radar (AMISR). AMISR's ground-based observations at high latitudes will provide essential contextual information for in situ, orbital "snapshot" measurements by spacecraft missions such as the NASA Geospace Electrodynamics Connections (GEC) mission, a Solar Terrestrial Probe mission also recom- mended by the Committee. The Committee also emphasizes the scientific importance of investigating the complex space environments of other planets. Such investigations serve as rigorous tests of the ideas developed from the study of Earth's own environment while extending our knowledge base to other solar-system bodies. Therefore the Committee strongly recommends a NASA Jupiter Polar Mission (JPM), which will study energy transfer in a magnetosphere that, unlike Earth's, is powered principally by planetary rotation instead of by the solar wind. All previous missions to Jupiter have flown in or near the equatorial plane, leaving the energetically important polar regions unexplored. Challenge 4: Understanding the basic physical principles Or solar and space plasma physics. The heliosphere is a natural laboratory for the study of plasma physics, and a number of the initiatives proposed by the Committee will lead to advances in understanding fundamental plasma physical processes. For examples as noted ~ _ ~ _ - --- - r -- - --- - --- - - `~---~7 - - ~ - ~-- - <::7 - - ---~~~;~-- - ~- - -- - - -~ - -~-- ~ . above, MMS is specifically designed to study magnetic reconnection, a physical process of fundamental importance in all astrophysical systems, from the Earth to the solar system to our galaxy and beyond. To complement the observational study of such fundamental processes in naturally occurring solar system plasmas, the Survey Committee recommends vigorous support of existing NASA and NSF theory and modeling programs as well as support for new initiatives such as the Coupling Complexity Research Initiative, a joint NASA/NSF theory and modeling program. Challenge 5: Developing a near-real-time predictive capability for the impact of space weather on human activities. Most technologies that fly in space and some that are on Earth's surface are affected severely by the geomagnetic storms whose origins can be traced to the Sun. These events produce subsidiary space weather phenomena, such as the blackouts of high frequency communications and disturbances of satellite transmissions, including those from spacecraft such as the Global Positioning System. The high-energy solar particles can severely disrupt spacecraft operations and present serious radiation hazards to astronauts and to the crews and passengers of aircraft flying on polar routes. In addition to interfering with communications and navigation systems, strong geomagnetic storms often disturb spacecraft orbits because of increased drag in the high-altitude atmosphere, and they even have caused electric utility blackouts over wide areas. Both our understanding of the basic physics of space weather and our appreciation of its importance for human activity have increased considerably during recent years. Much remains to be learned, however, about processes- such as changes in the Earth's radiation that affect the environment in which many satellites operate; about the variations in the properties of the highest regions of the atmosphere that can adversely affect GPS navigation systems and high-frequency radio propagation; and, finally, about the changes that occur on the Sun that ultimately cause the detrimental effects of space weather. The Survey Committee has therefore ranked as its second highest priority in the moderate-program category the Geospace Missions of NASA's Living With a Star program. These missions consist of two pairs of spacecraft that will be instrumented to study, respectively, changes in the upper atmosphere and the behavior of the Earth's radiation belts during geomagnetic storms. Of critical importance both for our efforts to understand and predict space weather and for basic solar and space physics research is information about solar wind conditions prior to their reaching Earth. Such information is currently being provided by the NASA Advanced Composition Explorer (ACE) spacecraft and the NASA Wind satellite. However, both spacecraft are now operating beyond their design lifetimes. The Survey Committee considers it of paramount importance to ensure uninterrupted monitoring of the solar wind and therefore assigned

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Congressional Testimony 107 high priority to the implementation of an Upstream Solar Wind Monitor as a replacement for ACE and Wind. Given the operational importance of the measurements that such a monitor would provide, the Committee recommends that responsibility for its implementation be transferred from NASA to NOAA. The importance of space weather and of this challenge to national needs is also reflected in the high prioritization that the Committee assigned to the multi-agency National Space Weather Program. In addition to specific research initiatives to address the five science challenges, the Survey Committee gave careful consideration to the "infrastructural" requirements for a robust solar and space physics research program during the coming decade. The Sun to the Earth and Beyond thus offers a number of recommendations in the following areas: technology development, solar and space physics education, and space research policy and program management, including space weather policy. All of the recommendations in these areas are given in the Executive Summary attached to my statement, so I will summarize only a few of the key ones here. High-priority areas of technology development identified by the Survey Committee include advanced propulsion and power, highly miniaturized spacecraft, advanced spacecraft subsystems, and highly miniaturized sensors of charged and neutral particles and photons. A number of initiatives in these areas are already under way within NASA such as the New Millennium Program, the Sun-Earth Connection and Living With a Star instrument development programs, and the In-Space Propulsion program, and the Committee strongly endorses these initiatives. The Survey Committee's consideration of issues related to education was driven by two main concems: how to provide a sufficient number of trained scientists to carry out the research program set forth in The Sun to the Earth and Beyond and how solar and space physics can contribute to the development of a scientifically and technologi- cally literate public. Here I will mention only one of the Survey Committee's recommendations namely, that NSF and NASA jointly establish a program to provide partial salary, start-up funding, and research support for four new faculty members a year for five years in the field of solar and space physics. I was pleased to learn recently that the NSF has already taken significant steps in this direction. Such a program will augment the number of university faculty in solar and space physics and is essential for a strong national solar and space physics research program during the coming decade. As I noted earlier, in my comments on the space weather challenge, the Survey Committee strongly recom- mends that NOAA assume responsibility for the implementation of an upstream solar wind monitor. Other Survey Committee recommendations regarding space weather policy address measures to facilitate the transition from research to operations, the acquisition and availability of data on solar activity and the geospace environment, and the roles of the public and private sectors in space weather applications. NOAA and the DOD as the two operational agencies, are primarily responsible for implementing most of the Survey Committee's recommenda- tions in this area. Finally, the Survey Committee developed a number of policy recommendations for strengthening the national solar and space physics research program. For example, a vital space research program depends on cost-effective, reliable, and readily available access to space that meets the requirements of a broad spectrum of missions. The Survey Committee therefore recommends revitalization of NASA's Suborbital Program, the development by NASA of a range of low-cost launch vehicles, and the establishment of procedures of "ride shares" on DOD (and possibly foreign) launch vehicles. The Committee also addressed the impact of export controls on solar and space physics research, which inevitably involves international collaboration, and recommended that the relevant federal agencies implement procedures to expedite international collaborations involving exchanges of scientific data or information on instrument characteristics. Let me now conclude my comments with a quote from Marcel Proust: "The real voyage of discovery consists not in seeking new landscapes, but in having new eyes." The solar and space physics research program envisioned by the Survey Committee for the coming decade offers both: visits to new solar system landscapes the unexplored near-Sun region, Jupiter's polar magnetosphere and the "new eyes" of observational initiatives such as MMS FASR, and AMISR and of advanced theoretical and computational initiatives such as the Coupling Complexity Research Initiative, which will enable us to "see" the fundamental connections underlying the complex phenomena captured in our observational data.