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13
Establishing a Life and Physical Sciences
Research Program: An Integrated
Microgravity Research Portfolio
NASA has a strong and successful track record in human spaceflight made possible by a backbone of sci -
entific and engineering research accomplishments. At this time, the United States finds itself at a stage where
future decisions regarding space exploration and activities will depend on the generation of new knowledge in
the life and physical sciences to ensure successful implementation of the human exploration options chosen. This
decadal survey identifies a number of research questions that need to be addressed to provide a sound basis for
any future crewed space program, as well as research questions that can be addressed uniquely using the space
environment. The relative urgency of resolving these questions will depend on policy decisions about the future
direction of the space exploration program. For example, conducting an extended crewed mission to the Moon
or beyond will require a focus on one set of priorities, whereas capitalizing on space assets to resolve terrestrial
scientific challenges will involve a different set of priorities. Irrespective of such policy decisions, however, the
committee concluded that a number of fundamental questions and research areas will have to be addressed as part
of an integrated approach that allows sufficient flexibility for policymakers to choose viable, cost-effective paths
for the U.S. crewed space program in the future. Some of these research areas relate to understanding the impacts
of extended exposure to microgravity conditions and how to mitigate those impacts. Other fundamental research
areas address the need for technological advances that can reduce the cost of space exploration, as well as the
challenges posed for humans by extended space travel with only very remote possibilities for logistical support
and replenishment. These questions are identified and priorities discussed in the preceding chapters, with Chapters
4 through 10 each focusing on a number of specific research disciplines in a related area.
In this chapter, the committee presents an integrated research portfolio that synthesizes the highest-priority
recommendations developed in Chapters 4 through 10 by the panels and the committee that reflects broad priorities
that cut across all the discipline areas. The committee believes that the research questions crystallized through the
individual panels and summarized in this chapter go to the core of challenges that need to be resolved to advance
future human space exploration. It is understood that as a result of scientific gains, additional questions and issues
may arise that will need novel solutions beyond the priorities and recommendations listed in this report. However,
the committee believes that a plan with sufficient flexibility with regard to an order of implementation is provided
here to serve as a blueprint, when guided by overall directions and goals identified by informed policymakers, for
NASA to expand and refine its space exploration program.
It is also the committee’s strong belief that undertaking an integrated portfolio of research will require pro -
grammatic reforms at NASA to establish a strong life and physical sciences enterprise, as discussed in Chapter 12.
379
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380 RECAPTURING A FUTURE FOR SPACE EXPLORATION
BOX 13.1
Summary of Support for NASA’s Robust Life and Physical
Sciences Research Program, 1996-2001
In fiscal year 1996 the budget for NASA’s Office of Life and Microgravity Science and Applications
covered a portfolio that mirrors much of the set of integrated recommendations presented in this report as
well as the development of a great deal of hardware for the conduct of that portfolio on the International
Space Station (ISS). By 2001, some hardware was still being developed, but hardware expenditures had
dropped off significantly, allowing the number of funded tasks to begin to increase. By 2010, however, the
breadth of the portfolio had shrunk considerably, and the number of tasks had dropped by about two-thirds.
Currently there is no single source for obtaining a full accounting of all ground- and space-based life and
microgravity science research conducted by NASA, but by any measure both the content of the funded
current portfolio and the sum of supported tasks are considerably lower than in 1996-2001.
Fiscal Number Budget
of Tasksa
Year (million $) Program Contents
1996 872 ~500 Technology and applications for space research and human support in
space, environmental health (microbiology, toxicology, barophysiology,
and radiobiology), advanced life support, space human factors, advanced
space suits, space biology research, plant biology, combustion science,
materials science, fluids, fundamental physics, and supporting orbital
operations and research
2001 1,014 ~300 Advanced human support, biomedical countermeasures, gravitational
biology and ecology, microgravity research, materials science,
environmental health, tissue engineering, telescience, human factors,
radiation research
2010 364 ~150 Research supporting human exploration and ISS life and physical sciences
research, including the Human Research Program and the small portion of
research within the Exploration Technology Demonstration Program that is
related to life and physical sciences research
NOTE: Numbers obtained from NASA task books and presentations to the Committee for the Decadal
Survey on Biological and Physical Sciences in Space.
aCorrelates closely with number of principal investigators.
Such an enterprise will serve as a necessary foundation for the agency to build a solid, robust, and transparent
research base shaped by the recommendations from this decadal survey coupled with future policy directions.
The committee points out that a large integrated portfolio of research similar to the complete set of research
recommendations contained in this study was supported by NASA in the mid-1990s through the early 2000s
(Box 13.1).
PRIORITIZING RESEARCH
In assembling the recommended integrated portfolio of research, the committee has mapped the chapters’
highest-priority recommendations against eight prioritization criteria that it believes are relevant to broadly
informing policy decisions with regard to future space program options (Box 13.2). The recommendations address
unanswered questions related to the health and welfare of humans undertaking extended space missions; to tech -
nologies needed to support such missions; and to logistical issues potentially affecting the health of space travel -
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ESTABLISHING A LIFE AND PHYSICAL SCIENCES RESEARCH PROGRAM
BOX 13.2
Criteria Used for Categorization of Research Recommendations
In its categorization of research, whether basic, applied, or translational, the committee used the
following eight prioritization criteria developed to capture the potential value of the results of research
(information, engineered systems, publications, or new concepts).
• rioritization Criterion 1: The extent to which the results of the research will reduce uncertainty
P
about both the benefits and the risks of space exploration (Positive Impact on Exploration Efforts,
Improved Access to Data or to Samples, Risk Reduction)
• rioritization Criterion 2: The extent to which the results of the research will reduce the costs of
P
space exploration (Potential to Enhance Mission Options or to Reduce Mission Costs)
• rioritization Criterion 3: The extent to which the results of the research may lead to entirely new
P
options for exploration missions (Positive Impact on Exploration Efforts, Improved Access to Data
or to Samples)
• rioritization Criterion 4: The extent to which the results of the research will provide full or partial
P
answers to grand science challenges that the space environment provides a unique means to ad-
dress (Relative Impact Within Research Field)
• rioritization Criterion 5: The extent to which the results of the research are uniquely needed by
P
NASA, as opposed to any other agencies (Needs Unique to NASA Exploration Programs)
• rioritization Criterion 6: The extent to which the results of the research can be synergistic with
P
other agencies’ needs (Research Programs That Could Be Dual-Use)
• rioritization Criterion 7: The extent to which the research must use the space environment to
P
achieve useful knowledge (Research Value of Using Reduced-Gravity Environment)
• rioritization Criterion 8: The extent to which the results of the research could lead to either faster or
P
better solutions to terrestrial problems or to terrestrial economic benefit (Ability to Translate Results
to Terrestrial Needs)
The committee did not weight these criteria, a step that would require assumptions about policy deci-
sions not yet made, or subject to change in the future. The criteria and priorities outlined in this chapter,
based on clear metrics, provide a basis for a complete, transparent, and robust research program, which
the committee believes is required to fully address NASA’s future needs for the life and physical sciences
research essential to successful space exploration.
ers, such as adequate nutrition, exposure to radiation, thermoregulation, immune function, stress, and behavioral
aspects. The eight criteria listed in Box 13.2 are also offered as a tool that will allow further down-selection to a
focused research program that can support any future policy decisions and the associated technology development
or knowledge requirements.
Although suggestions are provided below for further prioritization of recommendations already identified
as being of the highest priority for specific research areas, none of these high-priority recommendations should
be interpreted as being unnecessary. Recognizing that the relative order in which the recommendations will be
addressed is likely to depend on the future directions of NASA’s exploration and research programs, the committee
underscores that all of the recommendations individually are of high merit and collectively constitute important
components of an integrated research portfolio. Adoption of such a portfolio will serve as a foundation for the
success of future U.S. space exploration efforts, which will require integration, diverse teams, and a translational
scientific approach as discussed in Chapter 12.
In addition to the recommendations forming an integrated research portfolio, most of the discipline panels
identified a set of important priorities more extensive than what is summarized in this chapter. Although the subset
of recommendations provided here should form the core of a renewed physical and life sciences research program,
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382 RECAPTURING A FUTURE FOR SPACE EXPLORATION
rebuilding an integrated program commensurate with the scale of past microgravity work by NASA will require
that the larger set of priorities identified by the panels also be considered as priorities for implementation. Some of
the key issues to be addressed in the integrated research portfolio are the effects of the space environment on life
support components, the management of the risk of infections to humans, behavior having an impact on individual
and group functioning, risks and effects of space missions on human physiological systems, fundamental physical
challenges, applied fluid physics and fire safety, and finally, translational challenges arising at the interface bridg -
ing basic and applied research in both the life and physical sciences.
Chapters 4 through 10 identify research questions important both to successful space exploration and to
advances in fundamental physics and biology enabled by access to space. These two, very connected concepts—
the science enabled by exploration and the science that enables exploration—speak strongly to the powerful role
of science within the human spaceflight endeavor. Each recommendation listed in Table 13.1 is identified by the
committee as either enabling or enabled by exploration. (Some of the recommended research fits both categories.)
Further, the research recommendations are also dependent on and define the resources needed to accomplish identi -
fied goals. Those resources include hardware and flight opportunities together with robust ground-based programs
that place highly evolved experiments in the best position for success upon access to spaceflight.
Ultimately, the research recommended in this decadal study must be further prioritized based on future policy
developments, a task that the information summarized in Tables 13.2 and 13.3 is meant to facilitate. Examples of
how these tables can be used to develop a research portfolio for a mission-focused policy decision and a knowledge-
focused policy decision (see Boxes 13.3 and 13.4 below in this chapter) are meant to indicate a possible approach,
and not to be prescriptive.
FACILITY AND PLATFORM REQUIREMENTS
Microgravity research facilities can be divided into two classes: space-based and ground-based. The Interna -
tional Space Station (ISS), discussed in Chapters 3 and 11, is the only space-based facility providing a long-term
environment for scientists worldwide to carry out microgravity experiments. Short-term space-based facilities are
free-flyers and satellites. Ground-based facilities include parabolic flights, drop towers and sounding rockets, bed
rest facilities, accelerators, and medical clinics. A research portfolio that draws on communities of investigators
using model organisms, robust technology, and all available ground and flight platforms will greatly facilitate this
endeavor. Such an approach will allow solidifying critical new discoveries, decrease the time from selection to
flight, shorten the discovery confirmation process, and enhance the outcomes of mission-driven life and physical
sciences research.
Ground-Based Research Platforms
Ground-based research provides the basis for the design of flight-based research and can, at low cost, address
fundamental scientific questions that enable space research and applications by resolving measurement and system
feasibility issues. Ground-based fundamental physics research in heat, mass, and momentum transport, materials
physics, combustion, and granular materials supports the design of human flight systems and launch capabilities.
Space radiation in particular can be simulated well in ground-based laboratories. Accelerators at the NASA Space
Radiation Laboratory at Brookhaven National Laboratory produce both high-energy protons and the energetic
nuclei of heavier elements, allowing focused, mechanistic studies of the biological consequences for mammalian
cells and other relevant model systems (plants, microbes, etc.) of exposure to radiation. Continued availability
of space radiation facilities to NASA investigators is critical, as is broad access provided in a timely fashion to
meet agency needs.
Aircraft (parabolic zero-gravity flight) and drop towers, which provide a few seconds of microgravity condi -
tions at a time, can enable tests of technical feasibility and also serve as platforms for experiments that can be
completed during a single drop or atmospheric flight. For translational programs such as in situ resource utilization
(ISRU), analog field tests can be used to demonstrate system interactions, to evaluate repair and maintenance needs,
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ESTABLISHING A LIFE AND PHYSICAL SCIENCES RESEARCH PROGRAM
TABLE 13.1 Summary of Highest-Priority Recommendations Made in Chapters 4 Through 10
Enabled by (EB)
Recommendation and/or Enabling (E)
Identifiera Recommendation Space Exploration
Plant and Microbial Biology (Chapter 4)
P1 Establish a microbial observatory program on the ISS to conduct long-term, EB
multigenerational studies of microbial population dynamics.
P2 Establish a robust spaceflight program of research analyzing plant and microbial EB
growth and physiological responses to the multiple stimuli encountered in spaceflight
environments.
P3 Develop a research program aimed at demonstrating the roles of microbial-plant systems EB/E
in long-term life support systems.
Behavior and Mental Health (Chapter 5)
B1 Develop sensitive, meaningful, and valid measures of mission-relevant performance for E
both astronauts and mission control personnel.
B2 Conduct integrated translational research in which long-duration missions are simulated E
specifically for the purpose of studying the interrelationships among individual
functioning, cognitive performance, sleep, and group dynamics.
B3 Determine the genetic, physiological, and psychological underpinnings of individual E
differences in resilience to stressors during extended space missions, with development of
an individualized medicine approach to sustaining astronauts during such missions.
B4 Conduct research to enhance cohesiveness, team performance, and effectiveness of EB/E
multinational crews, especially under conditions of extreme isolation and autonomy.
Animal and Human Biology (Chapter 6)
AH1 The efficacy of bisphosphonates should be tested in an adequate population of astronauts EB/E
on the ISS during a 6-month mission.
AH2 The preservation/reversibility of bone structure/strength should be evaluated when EB/E
assessing countermeasures.
AH3 Bone loss studies of genetically altered mice exposed to weightlessness are strongly EB
recommended.
AH4 New osteoporosis drugs under clinical development should be tested in animal models of EB
weightlessness.
AH5 Conduct studies to identify underlying mechanisms regulating net skeletal muscle protein EB/E
balance and protein turnover during states of unloading and recovery.
AH6 Conduct studies to develop and test new prototype exercise devices and to optimize EB/E
physical activity paradigms/prescriptions targeting multisystem countermeasures.
AH7 Determine the daily levels and pattern of recruitment of flexor and extensor muscles of EB
the neck, trunk, arms, and legs at 1 g and after being in a novel gravitational environment
for up to 6 months.
AH8 Determine the basic mechanisms, adaptations, and clinical significance of changes EB/E
in regional vascular/interstitial pressures (Starling forces) during long-duration space
missions.
AH9 Investigate the effects of prolonged periods of microgravity and partial gravity (3/8 or 1/6 EB/E
g) on the determinants of task-specific, enabling levels of work capacity.
AH10 Determine the integrative mechanisms of orthostatic intolerance after restoration of EB/E
gravitational gradients (both 1 g and 3/8 g).
continued
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384 RECAPTURING A FUTURE FOR SPACE EXPLORATION
TABLE 13.1 Continued
Enabled by (EB)
Recommendation and/or Enabling (E)
Identifiera Recommendation Space Exploration
AH11 Collaborative studies among flight medicine and cardiovascular epidemiologists are EB/E
recommended to determine the best screening strategies to avoid flying astronauts with
subclinical coronary heart disease that could become manifest during a long-duration
exploration-class mission (3 years).
AH12 Determine the amount and site of the deposition of aerosols of different sizes in the lungs EB/E
of humans and animals in microgravity.
AH13 Multiple parameters of T cell activation in cells should be obtained from astronauts before EB
and after re-entry to establish which parameters are altered during flight.
AH14 Both to address the mechanism(s) of the changes in the immune system and to develop EB/E
measures to limit the changes, data from multiple organ/system-based studies need to be
integrated.
AH15 Perform mouse studies of immunization and challenge on the ISS, using immune samples EB
acquired both prior to and immediately upon re-entry, to establish the biological relevance
of the changes observed in the immune system. Parameters examined need to be aligned
with those in humans influenced by flight.
AH16 Studies should be conducted on transmission across generations of structural and EB
functional changes induced by exposure to space during development. Ground-based
studies should be conducted to develop specialized habitats to support reproducing and
developing rodents in space.
Crosscutting Issues for Humans in the Space Environment (Chapter 7)
CC1 To ensure the safety of future commercial orbital and exploration crews, quantify post- EB/E
landing vertigo and orthostatic intolerance in a sufficiently large sample of returning ISS
crews, as part of the immediate post-flight medical exam.
CC2 Determine whether artificial gravity (AG) is needed as a multisystem countermeasure and E
whether continuous large-radius AG is needed or intermittent exercise within lower-body
negative pressure or short-radius AG is sufficient. Human studies in ground laboratories
are essential to establish dose-response relationships, and what gravity level, gradient,
rotations per minute, duration, and frequency are adequate.
CC3 Conduct studies on humans to determine whether there is an effect of gravity on E
micronucleation and/or intrapulmonary shunting or whether the unexpectedly low
prevalence of decompression sickness on the space shuttle/ISS is due to underreporting.
Conduct studies to determine operationally acceptable low suit pressure and hypobaric
hypoxia limits.
CC4 Determine optimal dietary strategies for crews and food preservation strategies that will E
maintain bioavailability for 12 or more months.
CC5 Initiate a robust food science program focused on preserving nutrient stability for 3 or E
more years.
CC6 Include food and energy intake as an outcome variable in dietary intervention trials in EB/E
humans.
CC7 Conduct longitudinal studies of astronauts for cataract incidence, quality, and pathology E
related to radiation exposures to understand both cataract risk and radiation-induced late
tissue toxicities in humans.
CC8 Expand the use of animal studies to assess space radiation risks to humans from cancer, E
cataracts, cardiovascular disease, neurologic dysfunction, degenerative diseases, and acute
toxicities such as fever, nausea, bone marrow suppression, and others.
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ESTABLISHING A LIFE AND PHYSICAL SCIENCES RESEARCH PROGRAM
TABLE 13.1 Continued
Enabled by (EB)
Recommendation and/or Enabling (E)
Identifiera Recommendation Space Exploration
CC9 Continue ground-based cellular studies to develop end points and markers for acute and E
late radiation toxicities, using radiation facilities that are able to mimic space radiation
exposures.
CC10 Expand understanding of gender differences in adaptation to the spaceflight environment EB/E
through flight- and ground-based research, particularly potential differences in bone,
muscle, and cardiovascular function and long-term radiation risks.
CC11 Investigate the biophysical principles of thermal balance to determine whether EB/E
microgravity reduces the threshold for thermal intolerance.
Fundamental Physical Sciences in Space (Chapter 8)
FP1 Research on complex fluids and soft matter. Microgravity provides a unique opportunity EB/E
to study structures and forces important to the properties of these materials without the
interference caused by Earth-strength gravity.
FP2 Understanding of the fundamental forces and symmetries of nature. High-precision EB
measurements in space can test relativistic gravity, fundamental high-energy physics, and
related symmetries in ways that are not practical on Earth. Novel effects predicted by new
theoretical approaches provide distinct signatures for precision experimental searches that
are often best carried out in space.
FP3 Research related to the physics and applications of quantum gases. The space environment EB/E
enables many investigations, not feasible on Earth, of the remarkably unusual properties
of quantum gases and degenerate Fermi gases.
FP4 Investigations of matter near a critical phase transition. Experiments that have already EB
been designed and brought to a level of flight readiness can elucidate how materials
behave in the vicinity of thermodynamically determined critical points. These
experiments, which require a microgravity environment, will provide insights into new
effects observable when such systems are driven away from equilibrium conditions.
Applied Physical Sciences in Space (Chapter 9)
AP1 Reduced-gravity multiphase flows, cryogenics and heat transfer database and modeling, EB/E
including phase separation and distribution (i.e., flow regimes), phase-change heat
transfer, pressure drop, and multiphase system stability.
AP2 Interfacial flows and phenomena (including induced and spontaneous multiphase flows EB/E
with or without phase change) relevant to storage and handling systems for cryogens and
other liquids, life support systems, power generation, thermal control systems, and other
important multiphase systems.
AP3 Dynamic granular material behavior and subsurface geotechnics to improve predictions E
and site-specific models of lunar and martian soil behavior.
AP4 Development of fundamentals-based strategies and methods for dust mitigation during E
advanced human and robotic exploration of planetary bodies.
AP5 Experiments on the ISS to understand complex fluid physics in microgravity, including EB
fluid behavior of granular materials, colloids and foams, biofluids, non-Newtonian and
critical point fluids, etc.
AP6 Fire safety research to improve methods for screening materials for flammability and fire E
suppression in space environments.
AP7 Combustion processes research, including reduced-gravity experiments with longer EB/E
durations, larger scales, new fuels, and practical aerospace materials relevant to future
missions.
continued
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386 RECAPTURING A FUTURE FOR SPACE EXPLORATION
TABLE 13.1 Continued
Enabled by (EB)
Recommendation and/or Enabling (E)
Identifiera Recommendation Space Exploration
AP8 Research on numerical simulation of combustion to develop and validate detailed single E
phase and multiphase combustion models for interpreting and facilitating combustion
experiments and tests.
AP9 Reduced-gravity research on materials synthesis and processing and control of EB/E
microstructure and properties, to improve the properties of existing and new materials on
the ground.
AP10 Development of new and advanced materials that enable operations in harsh space E
environments and reduce the cost of human space exploration.
AP11 Fundamental and applied research to develop technologies that facilitate extraction, EB/E
synthesis, and processing of minerals, metals, and other materials available on
extraterrestrial surfaces.
Translation to Space Exploration Systems (Chapter 10)
TSES1 Conduct research to address issues for active two-phase flow relevant to thermal E
management. (T1)
TSES2 To support zero-boiloff propellant storage and cryogenic fluid management technologies, E
conduct research on advanced insulation materials research, active cooling, multiphase
flows, and capillary effectiveness (T2), as well as active and passive storage, fluid
transfer, gauging, pressurization, pressure control, leak detection, and mixing
destratification (T3).
TSES3 NASA should enhance surface mobility; relevant research includes suited astronaut E
computational modeling, biomechanics analysis for partial gravity, robot-human testing
of advanced spacesuit joints and full body suits, and musculoskeletal modeling and
suited range-of-motion studies (T4), plus studies of human-robot interaction (including
teleoperations) for the construction and operation of planetary surface habitats (T26).
TSES4 NASA should develop and demonstrate technologies to mitigate the effects of dust E
on extravehicular activity (EVA) systems and suits, life support systems, and surface
construction systems. Supporting research includes impact mechanics of particulates,
design of outer-layer dust garments, advanced material and design concepts for
micrometeoroid mitigation, magnetic repulsive technologies, and the quantification of
plasma electrodynamic interactions with EVA systems (T5); dynamics of electrostatic
field coupling with dust (T23); and regolith mechanics and gravity-dependent soil models
(T27).
TSES5 NASA should define requirements for thermal control, micrometeoroid and orbital debris E
impact and protection, and radiation protection for EVA systems, rovers, and habitats and
develop a plan for radiation shelters. (T19)
TSES6 NASA should conduct research for the development and demonstration of closed-loop E
life support systems and supporting technologies. Fundamental research includes heat and
mass transfer in porous media under partial gravity and microgravity conditions (T6) and
understanding the effect of variable gravity on multiphase flow systems. (T21, T22)
TSES7 NASA should develop and demonstrate technologies to support thermoregulation of E
habitats, rovers, and spacesuits on the lunar surface. (T20)
TSES8 NASA should perform critical fire safety research to develop new standards to qualify E
materials for flight and to improve fire and particle detectors. Supporting research is
necessary in materials qualification for ignition, flame spread, and generation of toxic
and/or corrosive gases (T7) and in characterizing particle sizes from smoldering and
flaming fires under reduced gravity (T8).
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ESTABLISHING A LIFE AND PHYSICAL SCIENCES RESEARCH PROGRAM
TABLE 13.1 Continued
Enabled by (EB)
Recommendation and/or Enabling (E)
Identifiera Recommendation Space Exploration
TSES9 NASA should develop a standard methodology for qualifying fire suppression systems E
in relevant atmospheres and gravity levels and would benefit from strategies for safe
post-fire recovery. Specific research is needed to characterize the effectiveness of fire
suppression agents and systems under reduced gravity (T9) and to assess the toxicity of
various fire products (T10).
TSES10 Research should be conducted to allow regenerative fuel cell technologies to be E
demonstrated in reduced-gravity environments. (T11)
TSES11 To support the development of new energy conversion technologies, research should E
be done on high-temperature energy conversion cycles, device coupling to essential
working fluids, heat rejection systems, materials, etc. (T12). Research is also required
on more efficient surface-base primary power and on the technologies to enable solar
electric propulsion as an option to transfer large masses of propellant and cargo to distant
locations (T18).
TSES12 To make fission surface power systems a viable option, research is needed on high- E
temperature, low-weight materials for power conversion and radiators and on other
supporting technologies. (T13)
TSES13 Development and demonstration of ascent and descent system technologies are needed, E
including ascent/descent propulsion technologies, inflatable aerodynamic decelerators, and
supersonic retro propulsion systems. The required research includes propellant ignition,
flame stability, and active thermal control (T14); lightweight flexible materials (T15); and
rocket plume aerothermodynamics and vehicle dynamics and control (T16).
TSES14 Research is required to support the development and demonstration of space nuclear E
propulsion systems, including liquid-metal cooling under reduced gravity, thawing under
reduced gravity, and system dynamics. (T17)
TSES15 Research is needed to identify and adapt excavation, extraction, preparation, handling, and E
processing techniques for a lunar water/oxygen extraction system. (T24)
TSES16 NASA should establish plans for surface operations, particularly ISRU capability E
development and surface habitats. Research is needed to characterize resources available
at lunar and martian surface destinations (T25) and to define surface habitability systems
design requirements (T28).
aIdentifiers correspond to the identifiers given to the highest-priority recommendations listed at the ends of Chapters 4 through 10, which
provide context and clarifying discussion.
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TABLE 13.2 Highest-Priority Recommendations That Provide High Support in Meeting Each of Eight Specific Prioritization Criteria
388
(1) Positive
Impact on (3) Positive
Exploration (2) Potential to Impact on
Efforts, Improved Enhance Mission Exploration (5) Needs (6) Research (7) Research
Access to Data Options or to Efforts, Improved (4) Relative Unique to NASA Programs That Value of Using (8) Ability to
or to Samples, Reduce Mission Access to Data Impact Within Exploration Could Be Dual- Reduced-Gravity Translate Results to
Risk Reduction Costs or to Samples Research Field Programs Use Environment Terrestrial Needs
Life P2, P3, B1, B2, P3, B1, B2, B3, P3, B4, AH1, P1, P2, B3, B4, P1, P2, P3, AH1, B1, B2, B3, P1, B1, B4, B1, B2, B3, B4,
Sciences B3, B4, AH1, B4, AH6, AH9, AH2, AH3, AH5, AH9, AH10, AH2, AH3, AH4, B4, AH1, AH2, AH12, AH16 AH1, AH2, AH3,
AH2, AH3, AH5, AH10, AH11 AH6, AH7, AH8, AH11, AH16 AH5, AH6, AH7, AH3, AH4, AH5, AH4, AH5, AH6,
AH6, AH7, AH8, AH9, AH10, AH8, AH9, AH6, AH7, AH9, AH7
AH9, AH10, AH11 AH10, AH11, AH10
AH11 AH16
Translational CCH2, CCH4, CCH2, CCH4, CCH2, CCH4, CCH2, CCH6 CCH1, CCH2, CCH1, CHH2,
Life CCH7 CCH6, CCH7 CCH6, CCH7, CHH3, CCH6, CHH3, CCH7,
Sciences CCH8 CCH7, CCH8 CCH11
Physical AP1, AP4, AP6, AP1, AP2, AP10, AP1, AP2, AP3, FP1, FP2, FP3, AP1, AP2, AP3, AP7, AP8, AP9, FP1, FP2, FP3, AP1, AP2, AP7,
Sciences AP8, AP11 AP11 AP10, AP11 AP5, AP7, AP8, AP4, AP6, AP11 AP10 FP4, AP1, AP2, AP8, AP9
AP9 AP5, AP6, AP7,
AP9
Translational TSES1, TSES2, TSES1, TSES3, TSES14 TSES2, TSES3, TSES10, TSES1, TSES2, TSES10
Physical TSES3, TSES14 TSES5, TSES10 TSES4, TSES5, TSES11, TSES12 TSES3, TSES4,
Sciences TSES6, TSES7, TSES5, TSES12,
TSES12, TSES13,
TSES13, TSES14,
TSES14, TSES TSES15, TSES16
16
NOTE: Identifiers are as listed in Table 13.1 and correspond with the recommendations listed there and also presented with clarifying discussion in Chapters 4 through 10.
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TABLE 13.3 Level of Support Provided by High-Priority Recommendations for Each of Eight Prioritization Criteria
(1) Positive
Impact on (3) Positive
Recommendation Exploration Impact on
Identifiera Efforts, (2) Potential to Exploration
Within Improved Access Enhance Mission Efforts, (5) Needs (6) Research (7) Research (8) Ability to
Suggested to Data or to Options or to Improved Access (4) Relative Unique to NASA Programs That Value of Using Translate Results
Program Samples, Risk Reduce Mission to Data or to Impact Within Exploration Could Be Dual- Reduced-Gravity to Terrestrial
Elements Reduction Costs Samples Research Field Programs Use Environment Needs
Plant and Microbial Biology Research
High High High
P1 Medium Low Low Medium Medium
High High High
P2 Medium Medium Medium Medium Medium
High High High High
P3 Low Medium Medium Medium
Human Behavior and Mental Health Research
High High High High High
B1 Low Medium Low
High High High High
B2 Low Medium Low Low
High High High High High
B3 Medium Low Low
High High High High High High High
B4 Medium
Animal and Human Biological Research
High High High High High
AH1 Medium Medium Medium
High High High High High
AH2 Medium Medium Medium
High High High High High
AH3 Medium Medium Medium
High High High
AH4 Medium Medium Medium Medium Medium
High High High High High
AH5 Medium Medium Medium
High High High High High High
AH6 Medium Medium
High High High High High
AH7 Medium Medium Medium
High High High
AH8 Medium Medium Medium Medium Medium
High High High High High High
AH9 Medium Medium
High High High High High High
AH10 Medium Medium
High High High High High
AH11 Medium Medium Medium
High
AH12 Medium Medium Medium Medium Medium Low Medium
AH13 Medium Low Medium Medium Medium Medium Medium Medium
AH14 Medium Low Medium Medium Medium Medium Medium Medium
AH15 Medium/Low Low Medium Medium Medium Medium Medium Medium
High High High
AH16 Medium/Low Medium/Low Medium/Low Low Medium
389
continued
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TABLE 13.3 Continued
390
(1) Positive
Impact on (3) Positive
Recommendation Exploration Impact on
Identifiera Efforts, (2) Potential to Exploration
Within Improved Access Enhance Mission Efforts, (5) Needs (6) Research (7) Research (8) Ability to
Suggested to Data or to Options or to Improved Access (4) Relative Unique to NASA Programs That Value of Using Translate Results
Program Samples, Risk Reduce Mission to Data or to Impact Within Exploration Could Be Dual- Reduced-Gravity to Terrestrial
Elements Reduction Costs Samples Research Field Programs Use Environment Needs
Crosscutting Research for the Human System
Low High High
CC1 Medium Low Low Low Medium
High High High High High High
CC2 Low Low
High High
CC3 Medium Medium Medium Low Low Low
High High High Medium
CC4 Medium Medium Medium Medium
CC5 Medium Medium Medium Medium Medium Medium Medium Medium
High High High High
CC6 Medium Medium Low Medium
High High High High High
CC7 Low Low Low
High High
CC8 Medium Medium Low Low Low Low
CC9 Medium Low Low Low Medium Low Low Low
CC10 Medium Medium/Low Medium Low Medium Medium Low Medium
CC11 Medium Medium/Low Medium Low Medium Medium/Low High/Medium Medium
Fundamental Physical Sciences Research
High High
FP1 Low Low Medium Low Medium Medium
High High
FP2 Low Low Low Low Medium Medium
High High
FP3 Low Low Medium Low Medium Medium
Medium High
FP4 Low Low Low Low Medium Medium
Applied Physical Sciences Research
High High High High High High
AP1 Medium Low
High High High High High
AP2 Medium Medium Medium
High High
AP3 Medium Medium Low N/A Low Low
High High
AP4 Medium Medium Low N/A Medium Low
High High
AP5 Low Low Medium Low Medium Medium
High High High
AP6 Medium Low Low Low Medium
High High High High
AP7 Medium N/A N/A Medium
High High High High
AP8 Medium Low Medium N/A
High High High High
AP9 N/A N/A Low Low
High High High
AP10 Low Medium Medium Low Medium
High High High High
AP11 Low N/A Medium N/A
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Translation to Space Exploration Systems Research
High High High
TSES1 Low Low Medium Medium Low
High High High
TSES2 High Medium Low Medium Medium
High High High High High
TSES3 Low Medium Medium
High High High
TSES4 Medium Medium Low Low Low
High High
TSES5 Medium Medium Low Low Medium Low
High
TSES6 Medium Medium Medium Low Low Medium Low
High High
TSES7 Medium Medium Low Medium Medium Medium
High
TSES8 Low Low Low Low Medium Medium Medium
High
TSES9 Low Low Low Low Medium Medium Medium
High High
TSES10 Medium Low Low Medium Medium Medium
High
TSES11 Medium Medium Low Low Medium Low Medium
High High High
TSES12 Medium Medium Low Low Medium
High High
TSES13 Medium Medium Low Low Medium Medium
High High High High
TSES14 Medium Medium Medium Medium
High
TSES15 Medium Medium Low Low Medium Low Low
High High
TSES16 Medium Medium Low Low Low Low
aIdentifiers are listed in Table 13.1 and correspond with the recommendations listed there and also presented the ends of Chapters 4 through 10, which provide context and clarifying
discussion.
391
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392 RECAPTURING A FUTURE FOR SPACE EXPLORATION
and to demonstrate long-lived operations. Terrestrial analog field tests are essential to demonstrate the long-term
reliability of candidate systems and to develop operational protocols.
Ground-based research is also important for the development of exercise countermeasures, including bed
rest studies. Findings from animal models have generated fundamental knowledge concerning the effects of
microgravity on muscle and bone physiology. Further, new avenues of animal research can unfold in the areas of
epigenetics of gene expression and protein turnover in response to unloading stimuli. Such ground-based studies
will benefit from shared specimens and data from space experiments using new technological approaches such
as transcript profiling.
Analog Environments
Analog environments (e.g., the ISS as an analog for remote and low-gravity planetary surfaces; polar and
undersea research facilities) and rigorously designed experimental simulations (e.g., long-duration chamber studies)
that faithfully mirror actual mission parameters (e.g., isolation, confinement, workload, long and uncertain time
duration, communication delays, disruption of diurnal sleep-wake cycles) can help to support a balanced research
portfolio. Analog opportunities offered through the ISS are discussed in Chapter 11.
Flight Platforms
Uncrewed flight opportunities on free-flyers provide a venue to conduct short-duration experiments, ideally
with an animal centrifuge available to provide proper 1-g controls for animal specimens and to address the impact
of microgravity on biological systems. Free-flyers are well suited for experiments involving virulent organisms or
toxic, radioactive, or otherwise dangerous materials that pose a risk to humans. Suborbital platforms and parabolic
flights are key in providing a short-duration microgravity environment for biological and physical sciences studies
of phenomena and behaviors that may show significant effects during the transitions between 1 g and microgravity
that will occur in planetary arrivals and departures.
Free-flying spacecraft can also be used for fundamental physics experiments that require an extremely low-
noise and low-stray-acceleration environment or a specific orbit. Future possibilities include a rotating free-flyer
(with or without a tether), perhaps with an emptied cargo vessel for long-duration experiments. Before ISS cargo
vessels are destroyed, they can potentially be used for relatively large-scale microgravity experiments, such as
fire safety tests. The absence of g-jitter also makes them an ideal platform for crystal growth experiments that are
particularly sensitive to vibrations.
Planetary or Lunar Surfaces as Platforms
Many biological processes are compromised in microgravity, and the gravity threshold for restoring proper
function is unknown. Availability of lunar bases for carrying out biological experimentation and for testing bio -
regenerative life support systems would allow assessment of whether biological functions will be normal (similar
to those in 1 g) in partial gravity. Lunar or martian bases would also be useful for conducting planetary research
described in other studies,1,2 such as fundamental seismographic studies, yielding insight into planets’ interiors and
their geological history, as well as allowing studies of their regolith compositions, magnetic fields, and atmospheric
phenomena (in the case of Mars) that are relevant to human exploration. In the longer term, such bases might also
be used as platforms for large telescopes and provide a stable, long-term laboratory setting for reduced-gravity
experimentation. Robotic exploration of the Moon could verify conditions near the lunar poles, develop resource
maps, and demonstrate ISRU system end-to-end operations in the lunar environment. Robotic missions may be
of particular importance for near-term exploration paths not directly focused on lunar exploration that could use
landers or compact rovers. Lunar assets, such as thermal wadis comprising regolith-derived thermal mass materials,
could serve as platforms that enable rovers and other exploration hardware to survive periods of cold and darkness.
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393
ESTABLISHING A LIFE AND PHYSICAL SCIENCES RESEARCH PROGRAM
Space Platforms for Research Beyond 2020
Although most of the recommendations in this report address the current decade, the committee recognizes
the long time constant inherent in the implementation of some of the recommendations and thus the importance
of planning for the period 2020-2029. The efforts for that decade include extension of research findings from the
2010-2019 decade and completion of remaining gaps. Although specific gaps are challenging to predict, it can
be expected that some projects started in the 2010-2019 decade will not reach maturity in that period. Likely to
be available in 2020-2029, for example, are new transport vehicles capable of carrying astronauts well beyond
low Earth orbit—emphasizing the need for research leading to compact low-power yet highly effective devices
that will provide countermeasures for changes in multiple human systems during long voyages in microgravity.
Further, the role of partial gravity in preventing deterioration in important physiological systems will have to be
clearly understood and countermeasures developed, if necessary, to mitigate those effects. NASA should therefore
consider a flexible infrastructure of experimental facilities that could be upgraded to novel exploration systems.
A lunar outpost established as a key national scientific resource could prove to be an important research plat -
form for ongoing studies in partial gravity, providing, among other benefits, sustainable research laboratories for
biological research on model systems addressing key scientific areas related to microgravity.
HIGHEST-PRIORITY RESEARCH AREAS AND OBJECTIVES
Table 13.1 summarizes, by discipline, the research elements selected by the panels, in close coordination with
the committee, as having the highest priority, and which this survey recommends for inclusion in NASA’s new
portfolio of biological and physical sciences research. The committee concluded that the elements listed in Table
13.1 are important in the creation of a compelling program of life and physical sciences research that can address
both fundamental scientific goals and exploration technology needs. These research elements are not described
in detail here; instead, unique identifiers listed in Table 13.1 allow locating related full descriptions in Chapters
4 through 10 (where each identifier is listed after a recommendation selected as having highest priority). These
identifiers are also shown in Tables 13.2 and 13.3, which map the research elements to the eight prioritization
criteria used by the committee. The committee believes that these recommended research areas are the most critical
to advancing the national space research program, and that these elements collectively constitute the core of an
integrated research portfolio in microgravity. It should be kept in mind that this list of recommendations represents
the distillation of priorities from an exceptionally large number of disciplines that have in the past typically been
treated in separate, more narrowly focused studies. Most of the panel chapters contain additional recommended
research—important to a program in that discipline—that was not selected for the integrated portfolio.
RESEARCH PORTFOLIO SELECTION OPTIONS
In Table 13.2, the committee maps the highest-priority recommendations (each indicated by the unique identi -
fier listed in Table 13.1) from Chapters 4 through 10 to the eight prioritization criteria defined in Box 13.2. The
research areas listed under a given criterion in Table 13.2 are those categorized in Table 13.3 as providing “high”
support for that particular criterion. This mapping is intended to help provide a basis for policy-related ordering
of an integrated research portfolio, depending on future policy decisions.
As examples of how the information in Table 13.2 might be used, consider two bounding policy options that
could drive a research portfolio. The first is a decision to send humans to Mars (Box 13.3). Clearly Prioritization
Criteria 1 and 2 would be the most important for prioritizing the research to support this policy, and supporting
the associated recommended research areas in an integrated program with clear translational end points would be
essential. These translational end points must enable realization of specific design goals that would be unachiev -
able without successful research. In this first example Prioritization Criteria 3 and 5 would also have to be taken
into consideration when selecting the science necessary to achieve this policy goal.
The second sample policy option is a decision to hold off on advanced human missions until a new base of
capability is developed and to focus instead in the near term on advancing leading-edge science (Box 13.4) and
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394 RECAPTURING A FUTURE FOR SPACE EXPLORATION
BOX 13.3
Sample Bounding Policy Option One
Goal: Send Humans to Mars
Prioritization Criteria 1 and 2 will be the most important functions
in prioritizing research to support the goal of sending humans to
Mars, and a way must be found to support the recommendations
associated with these priorities in an integrated program with clear
translational end points. Prioritization Criteria 3 and 5 will also have
to be taken into consideration to achieve the science necessary to
achieve this policy goal.
Criterion 1. The extent to which the results of the research will
The efficacy of
reduce uncertainty about both the benefits and the risks of
bisphosphonates should
space exploration (Positive Impact on Exploration Efforts, be tested in an adequate
Improved Access to Data or to Samples, Risk Reduction) population of astronauts
on the ISS during a 6-
month mission.
Relevant research recommendations
Life sciences: P2, P3, B1, B2, B3, B4, AH1, AH2, AH3, AH5, AH6, AH7, AH8, AH9, AH10, AH11
Life sciences translational: CCH2, CCH4, CCH7
Physical sciences: AP1, AP4, AP6, AP8
Physical sciences translational: TSES1, TSES2, TSES3, TSES14
Criterion 2. The extent to which the results of the research will Research should be conducted in
support of zero-boiloff propellant
reduce the costs of space exploration (Potential to Enhance
storage and cryogenic fluid
Mission Options or to Reduce Mission Costs) management. Physical sciences
research includes studies of advanced
insulation materials, active cooling,
Relevant research recommendations multiphase flows, and capillary
effectiveness (T2), as well as active
and passive storage, fluid transfer,
gauging, pressurization, pressure
control, leak detection, and mixing
Criterion 3. The extent to which the results of the research may destratification (T3).
lead to entirely new options for exploration missions (Positive
Impact on Exploration Efforts, Improved Access to Data or to
Samples)
Relevant research recommendations
Criterion 5. The extent to which the results of research are
uniquely needed by NASA, as opposed to any other agencies
(Needs Unique to NASA Exploration Programs)
Relevant research recommendations
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395
ESTABLISHING A LIFE AND PHYSICAL SCIENCES RESEARCH PROGRAM
BOX 13.4
Sample Bounding Policy Option Two
Goal: Develop New Capabilities by Advancing Leading‐Edge Science
The goal of developing new capabilities by advancing leading-
edge science represents a decision to postpone an advanced
human mission until a new base of capability is developed with
which to plan. The focus in the near term will be on advancing
leading-edge science and the value of space assets to terrestrial
needs. In this case, Prioritization Criteria 4, 5, and 8 will have
primary importance, and Prioritization Criteria 6 and 7 may also
be of importance in building the integrated research portfolio that
best supports this policy goal.
Criterion 4. The extent to which the results of the research will
fully or partially answer grand science challenges that the space
Establish a “microbial
environment provides a unique means to address (Relative
observatory” program on the ISS
Impact Within Research Field) to conduct long-term multi-
generational studies of microbial
population dynamics.
Relevant research recommendations
Life sciences: P1, P2, B3, B4, AH9, AH10, AH11, AH16
Life sciences translational: CCH2, CCH6
Microgravity provides a unique
Physical sciences: FP1, FP2, FP3, AP5, AP7, AP8, AP9 opportunity to study long time
dynamics of colloids, polymer
Physical sciences translational: None and colloidal gels, foams,
emulsions, and soap solutions
free from gravitational
Criterion 5. The extent to which the results of the research are interference.
uniquely needed by NASA, as opposed to any other agencies
(Needs Unique to NASA Exploration Programs)
Relevant research recommendations
Criterion 8. The extent to which the results of the research
could lead to either faster or better solutions to terrestrial
problems or to terrestrial economic benefit (Ability to Translate
Results to Terrestrial Needs)
Relevant research recommendations
Criterion 6. The extent to which the results of Criterion 7. The extent to which the research
the research can be synergistic with other must use the space environment to achieve
agencies’ needs (Research Programs That Could useful knowledge (Research Value of Using
Be Dual‐Use) Reduced‐Gravity Environment)
Relevant research recommendations
Relevant research recommendations
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396 RECAPTURING A FUTURE FOR SPACE EXPLORATION
the value of our space assets to terrestrial needs. In this case, Prioritization Criteria 4, 5, and 8 would have primary
importance, and Prioritization Criteria 6 and 7 might also be of importance in building the integrated research
portfolio that best supports this policy goal.
In addition to providing a basis for prioritization, Table 13.2 also illustrates the interdependence among the
different individual research recommendations, none of which, as pointed out above, should be seen in isolation.
Although an exact order of dependency among the individual recommendations is not specified, their grouping
clearly indicates their interdependence and underscores the importance of an integrated approach.
TIMELINE FOR THE CONDUCT OF RESEARCH
The committee was tasked with developing a timeline for the conduct of its recommended research, and except
where indicated otherwise the panel chapters contain rough estimates—based on assumptions of robust program -
matic support and reasonable access to flight opportunities—of time frames for the individual research areas. The
committee identified priority areas and questions that need to be addressed during the present decade (2010-2020),
as well as more overarching areas going beyond 2020. It refrained from suggesting a detailed timeline for the
overall research portfolio, because this will depend to a major extent on future policy and funding decisions. It is
the committee’s belief and hope that the high-priority recommended research and its categorization according to
eight prioritization criteria will serve to inform policymakers about knowledge needed irrespective of decisions
that might favor long-term human space exploration, planetary surface habitation and presence, or more basic and
fundamental research. In the committee’s view, all of these endeavors will require a science portfolio integrated
so as to enable NASA to derive optimal benefits and science return from its investments in research, as well as
from support provided by other government agencies and/or commercial sources.
An integrated research portfolio can also enable the identification and execution of radical new options to
reduce cost and risk for the U.S. space program. Specifically, new options that offer significant reductions in cost
and/or risk can best be conceived and developed in the context of integrated solutions to science and engineering
challenges and inclusion of translational end points.
Many of the thematic chapters include information on the current status of research and what would be rea -
sonable expectations with regard to accomplishments for the decade 2010-2019 versus 2020 and beyond. Much
of this estimation is based on the time required to conduct experiments and on the near-term expected availability
of platforms for conducting research. For a detailed summary of the rationale for and the respective targets of
research for the decades 2010-2019 and 2020-2029, the reader is referred to each of the thematic chapters (4
through 10). In addition, the mapping of research areas to prioritization criteria presented in Table 13.2 offers an
approach to considering timelines for research, as does Table 13.3, in which the disciplinary panels have further
classified each high-priority recommendation as being of high, medium, or low applicability with respect to each
of the eight prioritization criteria.
The committee chose this tabular presentation to avoid redundancy and to provide a ready means for NASA
to identify specific components of an integrated research portfolio judged most likely to contribute to capability
and flexibility for achieving space exploration program goals, as represented by the eight prioritization criteria
shown. Thus, for example, in considering a martian exploration mission (see Box 13.3), each recommendation can
be seen in Table 13.2 as ranked at a finer granularity with regard to its importance in addressing that specific goal.
If NASA were to decide to increase synergism with other agencies in building its research program, the recom -
mendations most relevant to addressing this priority would be found under Prioritization Criteria 6 in Table 13.2,
and the relative importance of all identified high-priority recommendations for this specific action item would be
as indicated in Table 13.3.
The committee anticipates that the categorization offered in Table 13.3 will guide NASA’s decision making
on timeline and urgency issues. The committee realizes that a careful assessment of timeline goals will require a
comprehensive and broad overview of space-relevant research and will require a strong life and physical sciences
research organization in the agency. Hence, the programmatic focus and recommendations summarized in Chapter
12 will be a key mechanism to ensure that specific, thematic committee recommendations can be adapted to a
flexible timeline responsive to NASA’s overarching goals.
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ESTABLISHING A LIFE AND PHYSICAL SCIENCES RESEARCH PROGRAM
IMPACT OF SCIENCE ON DEFINING U.S. SPACE EXPLORATION POLICY
Implicit in this report are integrative visions of the science advances necessary to underpin and enable major
new components, revolutionary systems, and bold exploration architectures for human space exploration. Essential
to achieving affordable, safe, and productive space exploration systems, such advances are central to the U.S.
space exploration policy and agenda. Their system-level aspects are fully addressed in the technical literature cited
in Chapters 4 through 10. The panels drew on their collective knowledge of science and technology and both
the references and their associated issues to define the scientific barriers, unit-processes, and physical challenges
worthy of inclusion in the recommendations in this report.
Impediments to revitalizing the U.S. space exploration agenda include costs, past inability to accurately pre -
dict costs and schedule, and uncertainties about mission and crew risk. The technical communities recognize their
obligations to deal with those impediments. Indeed, typical flow-downs from science as discussed in this report
include improvements in function and efficiency, subsequent reductions in mass, and direct or implied reductions
in cost. The starting point for much of the life sciences research is reducing mission and crew risk, an undertak -
ing for which new understanding is required to make safe human passage possible to, for example, Mars. Better
scientific understanding will also greatly improve the fidelity of overall cost and schedule predictions associated
with development of new systems.
A few examples from preceding chapters of this report illustrate these points. One revolutionary and mis -
sion architecture-changing system involves on-orbit depots for cryogenic rocket fuels. The scientific foundations
required to make this Apollo-era notion a reality are specified in the report. For some lunar missions, such a depot
could produce the major cost savings of an Ares 1 launch system replacing the Ares 5. The highly publicized col -
lection or production of large amounts of water from the Moon or Mars will require scientific understanding of
how to retrieve and refine water-bearing materials from the extremely cold, rugged regions on those bodies. Once
produced, that water could be transported to surface bases or to orbiting facilities for conversion into liquid oxygen
and hydrogen by innovative solar-powered cryogenic processing systems and then stored in the on-orbit depots.
All of these hardware and systems implementations require or will be enhanced by new scientific understanding.
Such advances point the way to a new era in defining space exploration.
Part of gaining support for crewed Mars missions is being able to address with confidence the questions of
protecting the health, safety, and job performance capabilities of crew members during the months-long transits to
and from Mars. The life sciences research portfolio recommended in this report constitutes an integrated complex
of scientific pursuits pertaining to multiple different biological systems and aimed at reducing to a minimum the
health hazards of space explorers, thereby providing quantitative answers to the questions associated with visiting
Mars. In other words, sustained research successes are required before humans can safely go to Mars and return.
Thus, this report is much more than a catalog of research recommendations; it identifies the scientific resources
and provides tools to help in defining and developing with greater confidence the future of U.S. space exploration
and scientific discovery.
REFERENCES
1. National Research Council. 2003. New Frontiers in the Solar System: An Integrated Exploration Strategy. The National
Academies Press, Washington, D.C.
2. National Research Council. 2007. The Scientific Context for Exploration of the Moon. The National Academies Press,
Washington, D.C.
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