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NASA NTRS1977

Sports and Recreation

Among a number of solar energy tests being jointly conducted by NASA's Lewis Research Center and the Energy Research and Development Administration are a sun-powered refrigerator and a back-pack mounted power supply for radios. Both use solar cells, spacecraft power sources which convert sun energy into electricity. The refrigerator, which has potential utility for outdoor campers, is in operation at a trail construction camp in Isle Royale National Park, a remote wilderness in Michigan's Lake Superior where electricity is available only at park headquarters. Trail maintenance crews working in the back country get food supplies only once weekly; with refrigeration they can enjoy a more varied and nutritious diet. Solar cells provide power to run the refrigerator and to charge its batteries for an alternate power supply when sun is not available. At the request of Znyo National Forest personnel NASA-Lewis also developed a back-pack system. The lightweight solar cell pack (on the pack strap in photo) charges batteries for portable two-way radios used by trailguards, who are on patrol for as much as two weeks at a time. Guards want continuous communication with the District Station, but battery capacity precludes such operation. With the solar cell power supply, guards can use their radios 24 hours a day.A lightweight, higher-capacity oxygen bottle-derived from rocket propellant tank technology-proved an important aid in the 1976 ascent to the summit of Mt. Everest by members of the. American Bicentennial Everest Expedition.

Source record↗

NASA NTRS2006

Meteoritic Microfossils in Eltanin Impact Deposits

We report the unique occurrence of microfossils composed largely of meteoritic ejecta particles from the late Pliocene (2.5 Ma) Eltanin impact event. These deposits are unique, recording the only known km-sized asteroid impact into a deep-ocean (5 km) basin. First discovered as in Ir anomaly in sediment cores that were collected in 1965, the deposits contain nun-sized shock-melted asteroidal material, unmelted meteorite fragments (named the Eltanin meteorite), and trace impact spherules. Two oceanographic expeditions by the FS Polarstern in 1995 and 2001 explored approximately 80,000 sq-km. of the impact region, mapping the distribution of meteoritic ejecta, disturbance of seafloor sediments by the impact, and collected 20 new cores with impact deposits in the vicinity of the Freeden Seamounts (57.3S, 90.5W). Analyses of sediment cores show that the impact disrupted sediments on the ocean floor, redepositing them as a chaotic jumble of sediment fragments overlain by a sequence of laminated sands, silts and clays deposited from the water column. Overprinted on this is a pulse of meteoritic ejecta, likely transported ballistically, then settled through the water column. At some localities, meteoritic ejecta was as much as 0.4 to 2.8 g/cm2. This is the most meteorite-rich locality known on Earth.

Kyte, Frank T.↗

NASA NTRS2004

ISS Asset Tracking Using SAW RFID Technology

A team at the NASA Johnson Space Center (JSC) is undergoing final preparations to test Surface Acoustic Wave (SAW) Radio Frequency Identification (RFID) technology to track assets aboard the International Space Station (ISS). Currently, almost 10,000 U.S. items onboard the ISS are tracked within a database maintained by both the JSC ground teams and crew onboard the ISS. This barcode-based inventory management system has successfully tracked the location of 97% of the items onboard, but its accuracy is dependant on the crew to report hardware movements, taking valuable time away from science and other activities. With the addition of future modules, the volume of inventory to be tracked is expected to increase significantly. The first test of RFID technology on ISS, which will be conducted by the Expedition 16 crew later this year, will evaluate the ability of RFID technology to track consumable items. These consumables, which include office supplies and clothing, are regularly supplied to ISS and can be tagged on the ground. Automation will eliminate line-of-sight auditing requirements, directly saving crew time. This first step in automating an inventory tracking system will pave the way for future uses of RFID for inventory tracking in space. Not only are there immediate benefits for ISS applications, it is a crucial step to ensure efficient logistics support for future vehicles and exploration missions where resupplies are not readily available. Following a successful initial test, the team plans to execute additional tests for new technology, expanded operations concepts, and increased automation.

Schellhase, Amy↗

NASA NTRS2007

Organization and Management of the International Space Station (ISS) Multilateral Medical Operations

The goal of this work is to review the principles, design, and function of the ISS multilateral medical authority and the medical support system of the ISS Program. Multilateral boards and panels provide operational framework, direct, and supervise the ISS joint medical operational activities. The Integrated Medical Group (IMG) provides front-line medical support of the crews. Results of ongoing activities are reviewed weekly by physician managers. A broader status review is conducted monthly to project the state of crew health and medical support for the following month. All boards, panels, and groups function effectively and without interruptions. Consensus prevails as the primary nature of decisions made by all ISS medical groups, including the ISS medical certification board. The sustained efforts of all partners have resulted in favorable medical outcomes of the initial fourteen long-duration expeditions. The medical support system appears to be mature and ready for further expansion of the roles of all Partners, and for the anticipated increase in the size of ISS crews.

Duncan, J. M.↗

NASA NTRS2007

Assessing the Biohazard Potential of Putative Martian Organisms for Exploration Class Human Space Missions

Exploration Class missions to Mars will require precautions against potential contamination by any native microorganisms that may be incidentally pathogenic to humans. While the results of NASA's Viking biology experiments of 1976 have been generally interpreted as inconclusive for surface organisms, the possibility of native surface life has never been ruled out and more recent studies suggest that the case for biological interpretation of the Viking Labeled Release data may now be stronger than it was when the experiments were originally conducted. It is possible that, prior to the first human landing on Mars, robotic craft and sample return missions will provide enough data to know with certainty whether or not future human landing sites harbor extant life forms. However, if native life is confirmed, it will be problematic to determine whether any of its species may present a medical risk to astronauts. Therefore, it will become necessary to assess empirically the risk that the planet contains pathogens based on terrestrial examples of pathogenicity and to take a reasonably cautious approach to bio-hazard protection. A survey of terrestrial pathogens was conducted with special emphasis on those pathogens whose evolution has not depended on the presence of animal hosts. The history of the development and implementation of Apollo anticontamination protocol and recent recommendations of the NRC Space Studies Board regarding Mars were reviewed. Organisms can emerge in nature in the absence of indigenous animal hosts and both infectious and non-infectious human pathogens are theoretically possible on Mars. The prospect of Martian surface life, together with the existence of a diversity of routes by which pathogenicity has emerged on Earth, suggests that the possibility of human pathogens on Mars, while low, is not zero. Since the discovery and study of Martian life can have long-term benefits for humanity, the risk that Martian life might include pathogens should not be an obstacle to human exploration. As a precaution, however, it is recommended that EVA suits be decontaminated when astronauts enter surface habitats when returning from field activity and that biosafety protocol approximating laboratory BSL 2 be developed for astronauts working in laboratories on the Martian surface. Quarantine of astronauts and Martian materials arriving on Earth should also be part of a human Mars mission and this and the surface biosafety program should be integral to human expeditions from the earliest stages of the mission planning.

Warmflash, David↗

NASA NTRS2007

Human Space Exploration: The Moon, Mars, and Beyond

America is returning to the Moon in preparation for the first human footprint on Mars, guided by the U.S. Vision for Space Exploration. This presentation will discuss NASA's mission, the reasons for returning to the Moon and going to Mars, and how NASA will accomplish that mission in ways that promote leadership in space and economic expansion on the new frontier. The primary goals of the Vision for Space Exploration are to finish the International Space Station, retire the Space Shuttle, and build the new spacecraft needed, to return people to the Moon and go to Mars. The Vision commits NASA and the nation to an agenda of exploration that also includes robotic exploration and technology development, while building on lessons learned over 50 years of hard-won experience. Why the Moon? Many questions about the Moon's potential resources and how its history is linked to that of Earth were spurred by the brief Apollo explorations of the 1960s and 1970s. This new venture will carry more explorers to more diverse landing sites with more capable tools and equipment for extended expeditions. The Moon also will serve as a training ground before embarking on the longer, more difficult trip to Mars. NASA plans to build a lunar outpost at one of the lunar poles, learn to live off the land, and reduce dePendence on Earth for longer missions. America needs to extend its ability to survive in hostile environments close to our home planet before astronauts will reach Mars, a planet very much like Earth. NASA has worked with scientists to define lunar exploration goals and is addressing the opportunities for a range of scientific study on Mars. In order to reach the Moon and Mars within a lifetime and within budget, NASA is building on common hardware, shared knowledge, and unique experience derived from the Apollo Saturn, Space Shuttle and contemporary commercial launch vehicle programs. The journeys to the Moon and Mars will require a variety of vehicles, including the Ares I Crew Launch Vehicle, which transports the Orion Crew Exploration Vehicle, and the Ares V Cargo Launch Vehicle, which transports the Lunar Surface Access Module. The architecture for the lunar missions will use one launch to ferry the crew into orbit, where it will rendezvous with the Lunar Module in the Earth Departure Stage, which will then propel the combination into lunar orbit. The imperative to explore space with the combination of astronauts and robots will be the impetus for inventions such as solar power and water and waste recycling. This next chapter in NASA's history promises to write the next chapter in American history, as well. It will require this nation to provide the talent to develop tools, machines, materials, processes, technologies, and capabilities that can benefit nearly all aspects of life on Earth. Roles and responsibilities are shared between a nationwide Government and industry team. The Exploration Launch Projects Office at the Marshall Space Flight Center manages the design, development, testing, and evaluation of both vehicles and serves as lead systems integrator. A little over a year after it was chartered, the Exploration Launch Projects team is testing engine components, refining vehicle designs, performing wind tunnel tests, and building hardware for the first flight test of Ares I-l, scheduled for spring 2009. The U.S. Vision for Space Exploration lays out a roadmap for a long-term venture of discovery. This endeavor will inspire and attract the best and brightest students to power this nation successfully to the Moon, Mars, and beyond. If one equates the value proposition for space with simple dollars and cents, the potential of the new space economy is tremendous, from orbital space delivery services for the International Space Station to mining and solar energy collection on the Moon and asteroids. The Vision for Space Exploration is fundamentally about bringing the resources of the solar system within the economic sphere of humaind. Given the immense size of our solar system, the amount of available material and energy within it present an enormous economic opportunity.

Sexton, Jeffrey D.↗

NASA NTRS2006

Adapting Analysis Tools to Engine Externals Analysis

Market forces are driving industry to reproduce product cycle time (the time required to conceive, design, build, test, validate and deliver a product). Application of existing tools in new areas can reduce the time required to design a new product and increase the confidence of acceptable test results later in the expensive testing and validation phase. Finite element methods, computational fluid dynamics codes and sharing of CAD datasets when applied to the design of engine externals can provide methods for product improvement and expedited delivery to the customer.

Dunkelberg, Ken↗

NASA NTRS1997

Weaving and bonding method to prevent warp and fill distortion

A method to prevent fiber distortion in textile materials employed in a modified weaving process. In a first embodiment, a tacifier in powder form is applied to the yarn and melted while on the fabric. Cool air is then supplied after the tacifier has melted to expedite the solidification of the tacifier. In a second embodiment, a solution form of a tacifier is used by dissolving the tacifier into a solvent that has a high evaporation rate. The solution is then sprayed onto the fabric or fill yarn as each fill yarn is inserted into a shed of the fabric. A third embodiment applies the tacifier in a liquid form that has not been dissolved in a solvent. That is, the tacifier is melted and is sprayed as a liquid onto the fabric or fill yarn as it is being extracted from a fill yarn spool prior to the fill yarn being inserted into the shed of the fabric. A fourth embodiment employs adhesive yarns contained as an integral part of the warp or fill yarn. Additional tacifier material is not required because a matrix is used as the tacifier. The matrix is then locally melted using heating elements on clamping bars or take-up rollers, is cooled, if necessary, and solidified.

Farley, Gary L.↗

NASA NTRS2007

Method and program product for determining a radiance field in an optical environment

A hybrid method is presented by which Monte Carlo techniques are combined with iterative relaxation techniques to solve the Radiative Transfer Equation in arbitrary one-, two- or three-dimensional optical environments. The optical environments are first divided into contiguous regions, or elements, with Monte Carlo techniques then being employed to determine the optical response function of each type of element. The elements are combined, and the iterative relaxation techniques are used to determine simultaneously the radiance field on the boundary and throughout the interior of the modeled environment. This hybrid model is capable of providing estimates of the under-water light field needed to expedite inspection of ship hulls and port facilities. It is also capable of providing estimates of the subaerial light field for structured, absorbing or non-absorbing environments such as shadows of mountain ranges within and without absorption spectral bands such as water vapor or CO.sub.2 bands.

Reinersman, Phillip N.↗

NASA NTRS2008

International Space Station Medical Operations

NASA is currently the leader, in conjunction with our Russian counterpart co-leads, of the Multilateral Medical Policy Board (MMPB), the Multilateral Medical Operations Panel (MMOP), which coordinates medical system support for International Space Station (ISS) crews, and the Multilateral Space Medicine Board (MSMB), which medically certifies all crewmembers for space flight on-board the ISS. These three organizations have representatives from NASA, RSA-IMBP (Russian Space Agency- Institute for Biomedical Problems), GCTC (Gagarin Cosmonaut Training Center), ESA (European Space Agency), JAXA (Japanese Space Agency), and CSA (Canadian Space Agency). The policy and strategic coordination of ISS medical operations occurs at this level, and includes interactions with MMOP working groups in Radiation Health, Countermeasures, Extra Vehicular Activity (EVA), Informatics, Environmental Health, Behavioral Health and Performance, Nutrition, Clinical Medicine, Standards, Post-flight Activities and Rehabilitation, and Training. Each ISS Expedition has a lead Crew Surgeon from NASA and a Russian Crew Surgeon from GCTC assigned to the mission. Day-to-day issues are worked real-time by the flight surgeons and biomedical engineers (also called the Integrated Medical Group) on consoles at the MCC (Mission Control Center) in Houston and the TsUP (Center for Flight Control) in Moscow/Korolev. In the future, this may also include mission control centers in Europe and Japan, when their modules are added onto the ISS. Private medical conferences (PMCs) are conducted regularly and upon crew request with the ISS crew via private audio and video communication links from the biomedical MPSR (multipurpose support room) at MCC Houston. When issues arise in the day-to-day medical support of ISS crews, they are discussed and resolved at the SMOT (space medical operations team) meetings, which occur weekly among the International Partners. Any medical or life science issue that is not resolved at the SMOT can be taken to the Mission Management Team meeting, which occurs biweekly from MCC-Houston. This meeting includes the other International Partners and all flight support and console position representatives via teleconference. ISS Crew Surgeons have handled many medical conditions on orbit; including skin rashes, dental abscesses, lacerations, and STT segment EKG changes. Fortunately to date, there have not been any forced medical evacuations from the ISS. This speaks well for the implementation of the primary, secondary and even tertiary prevention strategies invoked by the Integrated Medical Group, as there were several medical evacuations during the previous Russian space stations.

Jones, Jeffrey A.↗

NASA NTRS2008

The Interaction of the Space Shuttle Launch and Entry Suits and Sustained Weightless on Astronaut Egress Locomotion

The purpose of this study was to determine the consequences of extended periods of weightlessness during space missions on astronauts f ability to perform a simulated contingency egress while wearing either of the Launch and Entry suits immediately after space flight. In our previous lab-based study of simulated contingency egress, we found only 4 of 12 non-astronauts wearing the Launch and Entry Suit (LES) successfully completed the simulated egress. However, 4 of 4 of the previous failures (when tested wearing the LES), were then successful in completing the test wearing the Advanced Crew Escape Suit (ACES). Therefore, this study tested 21 Astronaut Volunteers wearing either the LES or ACES while performing a simulated egress on a treadmill (TM) onboard the Crew Transportation Vehicle immediately after space flight at either the Kennedy Space Center or Edwards AFB. Astronauts walked for 400 meters at 1.6m/sec with g-suit inflation level set to preflight testing levels, visor down, breathing from the suit emergency O2 supply. Metabolic, heartrate, and perceived exertion data were collected during these post-flight tests. Exactly the same preflight simulated egress tests on a TM were performed in the lab at NASA/JSC by each crewmember at L-60. Preflight testing found 2 of the 21 crewmembers were unable to complete the simulated contingency egress. Postflight, 9 crew (8 ACES, 1 LES) completed the simulated contingency egress of 400 meters at 1.6m/sec. and 12 failed to meet that standard (7 ACES, 5 LES). Preflight physiological response tests failed to identify crew capable of performing the egress vs. those who failed. However, 18 of the 21 crew did make at least 2.67 minutes into the postflight egress testing. At that point in time, heartrate was higher (P <=.20) for the failures compared to the finishers. These findings indicate that NASA fs switch to the ACES for space flight crews should be expedited.

Greenisen, M. C.↗

NASA NTRS2008

Lunar Outpost Life Support Trade Studies

Engineering trade-off studies of life support system architecture and technology options were conducted for potential lunar surface mission scenarios within NASA's Constellation Program. The scenarios investigated are based largely on results of the NASA Lunar Architecture Team (LAT) Phase II study. In particular, the possibility of Hosted Sortie missions, the high cost of power during eclipse periods, and the potential to reduce life support consumables through scavenging, in-situ resources, and alternative EVA technologies were all examined. These trade studies were performed within the Systems Integration, Modeling and Analysis (SIMA) element of NASA's Exploration Life Support (ELS) technology development project. The tools and methodology used in the study are described briefly, followed by a discussion of mission scenarios, life support technology options and results presented in terms of equivalent system mass for various regenerative life support technologies and architectures. Three classes of repeated or extended lunar surface missions were investigated in this study along with several life support resource scenarios for each mission class. Individual mission durations of 14 days, 90 days and 180 days were considered with 10 missions assumed for each at a rate of 2 missions per year. The 14-day missions represent a class of Hosted Sortie missions where a pre-deployed and potentially mobile habitat provides life support for multiple crews at one or more locations. The 90-day and 180-day missions represent lunar outpost expeditions with a larger fixed habitat. The 180-day missions assume continuous human presence and must provide life support through eclipse periods of up to 122 hours while the 90-day missions are planned for best-case periods of nearly continuous sunlight. This paper investigates system optimization within the assumptions of each scenario and addresses how the scenario selected drives the life support system to different designs. Subsequently, these analysis results can be used to determine which technologies may be good choices throughout a broad range of architectures.

Lange, Kevin E.↗

NASA NTRS2008

An EXPRESS Rack Overview and Support for Microgravity Research on the International Space Station (ISS)

The EXpedite the PRocessing of Experiments to Space Station or EXPRESS Rack System has provided accommodations and facilitated operations for microgravity-based research payloads for over 6 years on the International Space Station (ISS). The EXPRESS Rack accepts Space Shuttle middeck type lockers and International Subrack Interface Standard (ISIS) drawers, providing a modular-type interface on the ISS. The EXPRESS Rack provides 28Vdc power, Ethernet and RS-422 data interfaces, thermal conditioning, vacuum exhaust, and Nitrogen supply for payload use. The EXPRESS Rack system also includes payload checkout capability with a flight rack or flight rack emulator prior to launch, providing a high degree of confidence in successful operations once an-orbit. In addition, EXPRESS trainer racks are provided to support crew training of both rack systems and subrack operations. Standard hardware and software interfaces provided by the EXPRESS Rack simplify the integration processes for ISS payload development. The EXPRESS Rack is designed to accommodate multidiscipline research, allowing for the independent operation of each subrack payload within a single rack. On-orbit operations began for the EXPRESS Rack Project on April 24, 2001, with one rack operating continuously to support high-priority payloads. The other on-orbit EXPRESS Racks operate based on payload need and resource availability. Over 50 multi-discipline payloads have now been supported on-orbit by the EXPRESS Rack Program. Sustaining engineering, logistics, and maintenance functions are in place to maintain hardware, operations and provide software upgrades. Additional EXPRESS Racks are planned for launch prior to ISS completion in support of long-term operations and the planned transition of the U.S. Segment to a National Laboratory.

Pelfrey, Joseph J.↗

NASA NTRS2004

Mars Express: The Exploration of Phobos

The origin, structure and composition of Phobos are essentially still unresolved issue, with major outcomes for understanding the origin and evolution of the Solar system, and of the Mars system. Several missions have been designed with this unique body the only target. Is Phobos a captured small body (and in this case, can we identify the degree of differentiation such a small object has undergone ?), or is there any co-generic process with Mars involved ? Are there still volatile species trapped, and if so where, and in what form ? What are the reciprocal contributions of Mars and Phobos material accreted in the other body? The number of key clues for deciphering the early solar system processes, the Mars-Phobos binary evolution, and the role Phobos could play in the future of Mars exploration (including human expeditions), are numerous, and exciting for a large community. Part of the answers are in the high resolution coverage of this object (optical and IR, for composition variation), and in its full spectral analysis, from UV to thermal IR : Mars Express is the unique mission to provide this opportunity, and orbit 756, August 22, a totally unique opportunity to approach Phobos so closely. OMEGA should provide all across Stickney, the deepest accessible material, and over more than 20 km along, a spatial resolution less than 200 m, and assess the composition (and possibly their variations) wrt silicates (mafic materials), oxides, and eventually hydrated minerals and organics. By no means we should miss this opportunity: no one would understand the rationale not to turn the instruments ON while so close, and pointing them towards the Phobos surface.

Phobos↗

NASA NTRS2006

Hubble Space Telescope 2004 Battery Update

Battery cell wear out mechanisms and signatures are examined and compared to orbital data from the six on-orbit Hubble Space Telescope (HST) batteries, and the Flight Spare Battery (FSB) Test Bed at Marshall Space Flight Center (MSFC), which is instrumented with individual cell voltage monitoring. The on-orbit HST batteries were manufactured on an expedited basis after the Challenger Shuttle Disaster in 1986. The original design called for the HST to be powered by six 50 Ah Nickel Cadmium batteries, which would have required a shuttle mission every 5 years for battery replacement. The decision to use NiH2 instead has resulted in a longer life battery set which was launched with HST in April 1990, with a design life of 7 years that has now exceeded 14+ years of orbital cycling. This chart details the specifics of the original HST NiH2 cell design. The HST replacement batteries for Service Mission 4, originally scheduled for Spring 2005, are currently in cold storage at NASA Goddard Space Flight Center (GSFC). The SM4 battery cells utilize slurry process electrodes having 80% porosity.

Hollandsworth, Roger↗

NASA NTRS2008

International Space Station Human Behavior and Performance Competency Model: Volume II

This document further defines the behavioral markers identified in the document "Human Behavior and Performance Competency Model" Vol. I. The Human Behavior and Performance (HBP) competencies were recommended as requirements to participate in international long duration missions, and form the basis for determining the HBP training curriculum for long duration crewmembers. This document provides details, examples, knowledge areas, and affective skills to support the use of the HBP competencies in training and evaluation. This document lists examples and details specific to HBP competencies required of astronauts/cosmonauts who participate in ISS expedition and other international long-duration missions. Please note that this model does not encompass all competencies required. While technical competencies are critical for crewmembers, they are beyond the scope of this document. Additionally, the competencies in this model (and subsequent objectives) are not intended to limit the internal activities or training programs of any international partner.

Schmidt, Lacey↗

NASA NTRS2008

International Space Station Human Behavior and Performance Competency Model: Volume I

This document defines Human Behavior and Performance (HBP) competencies that are recommended to be included as requirements to participate in international long duration missions. They were developed in response to the Multilateral Crew Operations Panel (MMOP) request to develop HBP training requirements for the International Space Station (ISS). The competency model presented here was developed by the ITCB HBPT WG and forms the basis for determining the HBP training curriculum for long duration crewmembers. This document lists specific HBP competencies and behaviors required of astronauts/cosmonauts who participate in ISS expedition and other international longduration missions. Please note that this model does not encompass all competencies required. For example, outside the scope of this document are cognitive skills and abilities, including but not limited to concentration, memorization, perception, imagination, and thinking. It is assumed that these skills, which are crucial in terms of human behavior and performance, are considered during selection phase since such professionally significant qualities of the operator should be taken into consideration in order to ensure sufficient baseline levels that can be further improved during general astronaut training. Also, technical competencies, even though critical for crewmembers, are beyond the scope of this document. It should also be noted that the competencies in this model (and subsequent objectives) are not intended to limit the internal activities or training programs of any international partner.

Schmidt, Lacey↗

NASA NTRS2006

Current ISS Exercise Countermeasures: Where are we now?

Current International Space Station (ISS) crew schedules include 1.5 h/d for completion of resistive exercise and 1 h/d of aerobic exercise , 6 d/wk. While ISS post flight decrements in muscle strength, bone m ineral density, and aerobic capacity improved in some crewmembers, de conditioning was still evident even with this volume of exercise. Res ults from early ISS expeditions show maximum loss in bone mineral density of the lumbar spine and pelvis in excess of 1.5% per month, with all crewmembers demonstrating significant bone loss in one or more re gions. Similarly, post flight muscle strength losses in the hamstring and quadriceps muscle groups exceeded 30% in the immediate post miss ion period in some crewmembers. Measures of aerobic capacity early in the mission show average decrements of 15%, but with onboard aerobic exercise capability, the crew has been able to "train up" over the co urse of the mission. These findings are highly variable among crewmem bers and appear to be correlated with availability and reliability of the inflight resistive exercise device (RED), cycle ergometer, and t readmill. This suite of hardware was installed on ISS with limited op erational evaluation in groundbased test beds. As a result, onorbit hardware constraints have resulted in inadequate physical stimulus, d econditioning, and increased risk for compromised performance during intra and extravehicular activities. These issues indicate that the c urrent ISS Countermeasures System reliability or validity are not ade quate for extendedduration exploration missions. Learning Objective: A better understanding of the status of ISS exercise countermeasures , their ability to protect physiologic systems, and recommendations for exploration exercise countermeasures.

Hayes, J. C.↗