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This viewgraph presentation reviews the International Space Station and the future of spaceflight. Pictures of robotics, planetary exploration, astrobiology, space tourism, and space commercialization are all shown.
Planetary Robotic and Human Spaceflight Exploration Humans are exposed to a great variety of hazards in the space environment. These include the effects of weightlessness, radiation, isolation and confinement, altered day-night cycles, and others. These inherent hazards have both physiological and behavioral consequences. The adaptive capabilities of humans in these situations is remarkable, and often exceed our expectations. However, the demanding environment and challenging operational pace can push some of these adaptive processes to their limits. The NASA Human Research Program (HRP) is tasked with mitigating the most serious of these effects on human health, safety, and performance, in long-duration space flight. This can involve the development and deployment of physiological countermeasures, better understanding of the physiological alterations and avoidance of exacerbating situations, inputs to the design of future spacecraft to minimize risks, and in some cases the awareness that some level of risk might have to be accepted based on the resulting consequences and their likelihood. HRP has identified a few areas that are of special concern due to their severity, lack of understanding of underlying causes, or potential for negative impact on health or performance. Some of these areas are visual impairment possibly due to increased intracranial pressure, behavioral and performance problems due to sleep deficits and isolation, and acute and chronic effects of radiation. These problems can, if not addressed, be expected to increase on longer and more distant missions. The evidence from spaceflight, laboratory, and analog studies that supports the selection of the most critical risks will be discussed. Current and planned research programs that address these risks, and their anticipated outcomes, will also be described.
Ultra-compact, ns-class spaceflight-compatible UV lasers are finding increasing application in laser desorption, excitation, and ionization analytical applications on planetary missions, such as the detection and characterization of potential molecular biosignatures on Mars or icy moon surfaces. A short pulsed, solid state, UV laser is under development with selectable pulse energy capabilities for optimized sample ion production at a planetary surface.
As the worlds space agencies and commercial entities continue to expand beyond Low Earth Orbit (LEO), novel approaches to carry out biomedical experiments with animals are required to address the challenge of adaptation to space flight and new planetary environments. The extended time and distance of space travel along with reduced involvement of Earth-based mission support increases the cumulative impact of the risks encountered in space. To respond to these challenges, it becomes increasingly important to develop the capability to manage an organisms self-regulatory control system, which would enable survival in extraterrestrial environments. To significantly reduce the risk to animals on future long duration space missions, we propose the use of metabolically flexible animal models as pathfinders, which are capable of tolerating the environmental extremes exhibited in spaceflight, including altered gravity, exposure to space radiation, chemically reactive planetary environments and temperature extremes.In this report we survey several of the pivotal metabolic flexibility studies and discuss the importance of utilizing animal models with metabolic flexibility with particular attention given to the ability to suppress the organism's metabolism in spaceflight experiments beyond LEO. The presented analysis demonstrates the adjuvant benefits of these factors to minimize damage caused by exposure to spaceflight and extreme planetary environments. Examples of microorganisms and animal models with dormancy capabilities suitable for space research are considered in the context of their survivability under hostile or deadly environments outside of Earth. Potential steps toward implementation of metabolic control technology in spaceflight architecture and its benefits for animal experiments and manned space exploration missions are discussed.
As the world's space agencies and commercial entities continue to expand beyond Low Earth Orbit (LEO), novel approaches to carry out biomedical experiments with animals are required to address the challenge of adaptation to space flight and new planetary environments. The extended time and distance of space travel along with reduced involvement of Earth-based mission support increases the cumulative impact of the risks encountered in space. To respond to these challenges, it becomes increasingly important to develop the capability to manage an organism's self-regulatory control system, which would enable survival in extraterrestrial environments. To significantly reduce the risk to animals on future long duration space missions, we propose the use of metabolically flexible animal models as "pathfinders," which are capable of tolerating the environmental extremes exhibited in spaceflight, including altered gravity, exposure to space radiation, chemically reactive planetary environments and temperature extremes. In this report we survey several of the pivotal metabolic flexibility studies and discuss the importance of utilizing animal models with metabolic flexibility with particular attention given to the ability to suppress the organism's metabolism in spaceflight experiments beyond LEO. The presented analysis demonstrates the adjuvant benefits of these factors to minimize damage caused by exposure to spaceflight and extreme planetary environments. Examples of microorganisms and animal models with dormancy capabilities suitable for space research are considered in the context of their survivability under hostile or deadly environments outside of Earth. Potential steps toward implementation of metabolic control technology in spaceflight architecture and its benefits for animal experiments and manned space exploration missions are discussed.
In response to a large public demand for information, the Educational Services Branch of NASA has undertaken a series of publications designed for use by teachers, titled 'Educational Briefs for the Classroom', which has resulted in six to eight issues each year for the last three years. Typical of the topics to which the series is dedicated have been space suits, manned spaceflight mission summaries, solar cells, planetary encounter data, orbits, and rocketry. The planning committee for Educational Briefs is aided in its selection of topics by the many letters received by NASA. Following the Voyager Saturn flybys, NASA received more than 175,000 letters from both children and adults.
Space travel, planetary probes, applications satellites, manned spaceflight, the impacts of space exploration, future space activities, astronomy, exobiology, aeronautics, energy, space and the humanities, and aerospace education are covered.
A series of virtual workshops was held during June 2020 to seek ways to integrate the efforts of the astrobiology and space biology research communities under a broad umbrella of space life sciences. The overall goal was to help inspire creativity that will guide us towards new synergistic ideas complementing these existing disciplines that are of such importance to NASA. Workshop participants aspired to: (1) Exploit synergies across the biological sciences at NASA, (2) Foster research, enabling technology, and mission concepts that support commonalities in space biology, astrobiology, synthetic biology, planetary protection, and relevant human health, performance, and habitation concerns, (3) Envision the development of an “Arc of Biology in Space” to encompass this multi-faceted joint research community. The focused objective of the workshop series was to explore and demonstrate how the integration of astrobiology and space biology could be achieved, identify strengths and weaknesses in the current state of the art, and recognize where our greatest challenges lay. Specifically, we seek to: (1) Establish a scientific framework for an integrated life sciences effort, (2) Pioneer discovery by creating unique opportunities in the fundamental biological sciences, (3) Explore novel combinations of existing technologies across the relevant disciplines, (4) Invent new technologies and applications in space life sciences, and (5) Creatively increase access to spaceflight, emerging and novel technologies, Earth analogs, and simulated natural and spaceflight environments. The community aims for a broad arc of biological competence in the context of space and planetary science, spaceflight, and habitation. We will present dominant themes and innovative ideas that resulted from this interchange of relevant communities.
A series of virtual workshops was held during June 2020 to seek ways to integrate the efforts of the astrobiology and space biology research communities under a broad umbrella of space life sciences. The overall goal was to help inspire creativity that will guide us towards new synergistic ideas complementing these existing disciplines that are of such importance to NASA. Workshop participants aspired to: (1) Exploit synergies across the biological sciences at NASA, (2) Foster research, enabling technology, and mission concepts that support commonalities in space biology, astrobiology, synthetic biology, planetary protection, and relevant human health, performance, and habitation concerns, (3) Envision the development of an “Arc of Biology in Space” to encompass this multi-faceted joint research community. The focused objective of the workshop series was to explore and demonstrate how the integration of astrobiology and space biology could be achieved, identify strengths and weaknesses in the current state of the art, and recognize where our greatest challenges lay. Specifically, we seek to: (1) Establish a scientific framework for an integrated life sciences effort, (2) Pioneer discovery by creating unique opportunities in the fundamental biological sciences, (3) Explore novel combinations of existing technologies across the relevant disciplines, (4) Invent new technologies and applications in space life sciences, and (5) Creatively increase access to spaceflight, emerging and novel technologies, Earth analogs, and simulated natural and spaceflight environments. The community aims for a broad arc of biological competence in the context of space and planetary science, spaceflight, and habitation. We will present dominant themes and innovative ideas that resulted from this interchange of relevant communities.
The possibility that life exists elsewhere in the universe, even in our own planetary system, has intrigued scientists, philosophers, and theologians for centuries. The spaceflight programs of NASA have provided much new information about our planetary neighbors and have put to rest some speculations about the existence of life on those planets or their satellites. However, there are still undetermined questions about the possibility of some form of life existing in the far distant past in our planetary system. Beyond our planetary system, the astronomical quest for scientific clues about life continues, largely via the radio telescope. Thus far there is no conclusive evidence. Here, some of the recent findings about our planetary neighbors are reviewed and the question about life elsewhere in the universe is addressed.
Radioisotope Thermoelectric Generators (RTGs) have been used to power NASA missions of various types throughout the past five decades. The most recent RTG iteration, used for NASA’s Mars Science Laboratory, is the Multi-Mission RTG (MMRTG), which is currently the only spaceflight-qualified system available. The U.S. planetary science community has expressed a desire for more power system options to be available to accommodate a range of ambitious future mission concepts across the solar system. Recent advancements in thermoelectric (TE) materials technology have raised a potential for significantly increased efficiency in future RTGs, which helped spur a recent in-depth NASA study of options for future systems. A “next-generation” RTG study was conducted to develop new RTG concepts that could meet the needs of planetary science missions through the 2030s and beyond. A Next-Generation RTG would aim to extend the types of potential NASA missions able to be supported, while fulfilling requirements related to technical risk and schedule. In this study, 21 potential thermoelectric couple configurations were analyzed by considering various high-performance, high-temperature TE materials and segmentation techniques that maximize convertor efficiency and power density. System modularity was explored, and found to be a promising means to offer improved flexibility for NASA mission concepts with varying scope and power requirements. This paper presents the results of the study, demonstrating the viability of developing an updated RTG system design, and defining conceptual system approaches for a new, potentially revolutionary RTG.
Design-Build-Test approaches for spaceflight hardware are time and cost intensive, which can result in suboptimal mechanism designs. Optimization-based approaches that utilize high-fidelity models and physics simulation could overcome these limitations while simultaneously speeding up the mechanical design process and reducing cost. In this work, we present a toolchain that enables the multi-objective optimization of rigid rover wheels for planetary surface mobility applications. The toolchain uses Chrono’s Continuous Representation Model (CRM) functionality to simulate granular soil and performs multi-objective parametric optimization on candidate rover wheels to meet a desired performance criterion. The resulting wheel design is then evaluated experimentally using a single-wheel testbed. We end with a discussion of how the toolchain can be extended to simultaneously co-optimize other system parameters, such as system power consumption and feedback control gains.
Given the accelerated declines in bone mineral density reported in US astronauts serving on the International Space Station, there is a possibility that a prolonged exposure to spaceflight could put astronauts at increased fracture risk during subsequent planetary explorations or after return to Earth. To date, there have been no fractures in astronauts during spaceflight. Recently-reported data from a flight study suggested that intake of the bisphosphonate alendronate combined with resistive exercise (on the Advanced Resistive Exercise Device – ARED) preserved more astronauts at their preflight skeletal status after a ~6-mos spaceflight than with ARED exercise alone. However, there is low acceptance of alendronate, or the recommended zoledronic acid, to suppress in-flight bone loss largely due to concern for unintended medication side effects and a perceived absence of astronaut fractures that can be directly attributable to spaceflight exposure. Hence, a recent survey of all astronaut fractures was analyzed to assess whether the rate of postflight fractures could be associated with extended spaceflight exposures. The fracture survey was of 262 astronauts across 8433.6 person-years (PY) and grouped according to previous exposure to a “Long Duration (LD)” spaceflight (3 mos or greater, but typically 6-mos). The number of fractures was modeled using count regression adjusting for i) the repeated measures within individuals across the groups, ii) the differing length of surveillance for each individual and iii) age at start of surveillance for each of the groups. Astronaut Group by Spaceflight Exposure #Individuals PY Covered No Exposure to Spaceflight 262 1882.7 No Exposure to LD spaceflight “Non-LD” 232 6121.3 Exposure to LD spaceflight 42 429.6 Analysis revealed an increased rate of hip and spine fractures for surveillance periods compared between LD Exposure and Non-LD Exposure: Hip – Relative Rate: 3.4 (95%CI: 1.0, 12.0); Spine– Relative Rate: 3.4 (95%CI: 1.0, 11.6). For all other skeletal sites, rates of fracture were similar for LD and Non-LD exposures. Data comparisons were conducted between groups of astronauts to preclude the interpretation of greater physical activity in astronauts as a contributing factor to fracture rates. This analysis of fracture data is the first report associating postflight hip and spine fractures in astronauts with exposure to extended duration spaceflights. Further analyses integrating co-morbidities for bone loss are planned.
BACKGROUND As NASA’s mission programs begin to shift from Low Earth Orbit (LEO) to planetary mission profiles, the importance of understanding the phenomena a human experience when returning from spaceflight is of increased importance. The purpose of this study was to assess trends across individuals in the symptoms experienced during the landing process of long duration ISS missions. METHODS Data for this study is an aggregation of mission level data from forms used by crew surgeons at R+0, electronic medical records, notes from weekly Space Medicine Operation Team meetings, records in the Shuttle Mission Data Archive, and data collected by research teams in the Human Research Program (HRP). Aggregated data was used in descriptive analysis of the trends in medical events and countermeasure use. The data was also used to identify high value targets for emphasis in on going surveillance efforts. RESULTS Completeness of reporting varied greatly over time and across missions dependent on information sources available for data extraction. Landing forms provided the most complete data but still missed or left unconfirmed, several, common symptoms, and countermeasures. Data aggregation did show to cover gaps within individual data sources. Commonly reported symptoms included nystagmus, vertigo, and nausea. Common protocols for fluid loading and meclizine are reflected within the data set. DISCUSSION The data set generated in this project provides a foundation that show how symptoms of astronauts as they return to Earth varies across the long duration ISS missions. While there is an abundance of information provided within the data set, there are still inconsistencies in reporting especially in the absence of the landing day form. Further data collection practices should be standardized to ease the burden on crew surgeons during R+0 exams and better collect high value variables.
Background: The National Aeronautics and Space Administration’s (NASA) Exploration Atmospheres study (EA) was done to evaluate alternative cabin atmospheres for future spacecraft designs and planetary surface exploration of the Moon, Mars and beyond. Deep space exploration involves creating habitats and environments safe for human occupancy and means to explore the outside environment (extravehicular activities, EVA). In order to validate alternative atmospheres and pre-spacewalk procedures, the EA study was conducted to evaluate factors such as hypoxia risks, denitrogenation protocols, food limitations, medications, and the impact of other factors on human performance. Overview: Space travel is constrained by mass, volume, power and the cost of vehicle development, which creates tradeoffs in various capabilities, including breathing gasses. Higher atmospheric pressure in a vehicle means more gas, and a stronger containment vessel/habitat; while lower pressure requires higher oxygen partial pressure, which may increase fire risk. NASA’s EA study evaluated a proposed alternative cabin environment (8.2 psia, 34% Oxygen), for future spacecraft habitat, and planetary EVAs. EA included both a 3-day and a 11-day trial. These trials included a depressurization and saturation to 8.2psi at 34% O2 with additional depresses to 4.3 psia at 85% O2 for simulated EVAs, (1 EVA during the 3-day and 5 during the 11-day trials). Discussion: Planning for and executing the medical monitoring and response plan for a trial of this scope was a huge undertaking with no prior practice to fall back on. Food obstacles, sleeping issues, medications, joint injury, equipment limitations, medical privacy, multiple cases of decompression sickness, and even a COVID outbreak among the support team proved challenging. Conclusion: Testing of this nature is an essential part NASA’s preparation for the upcoming Lunar Artemis missions. As spaceflight transitions beyond low earth orbit, to planetary, even more trials of this nature will be required to learn what are the optimal atmospheric and associated operational constraints to maintain the optimal health of the crew and achieve mission objectives.
NASA’s Planetary Systems Laboratory (PSL) at the Goddard Spaceflight Center in Greenbelt, Maryland is tasked with the study of solar system objects. This work is frequently based on analysis of imagery from visiting spacecraft, orbiting telescopes, and ground-based sensors. A consequence of this mission is the need to characterize features on the spherical surface of planets and moons, such characterization including the overall area of the feature, its center, its moments of inertia, its perimeter, its compactness, its major axis, its bounding box, its aspect ratio and its North-South orientation. Accurate assessment of these measures from a “flat” two-dimensional image is a challenge, since the scale of distance observed at the center of a spherical object distorts in any direction towards the horizon. PSL has developed a technique to guarantee accurate and automated measurement at any point on the visible surface, by overlaying an imaginary grid of equal-area cells onto the two-dimensional image of the sphere. The technique is named Grid-Oriented Normalization for Analysis of Spherical Areas (GONASA). This paper discusses the construction of the normalization grid and describes specific algorithms for feature parameterization. The algorithms are implemented in an accompanying Excel spreadsheet, both for clarity and ease of adoption, and to emphasize their aptness for automation. Finally, a concrete use case is offered where the GONASA grid and algorithms are used to characterize methane clouds on the Saturnian moon Titan.
An improved methodology for quantitatively evaluating failure risk for a spaceflight system in order to assess flight readiness is presented. This methodology is of particular value when information relevant to failure prediction, including test experience and knowledge of parameters used in engineering analyses of failure phenomena, is limited. In this approach, engineering analysis models that characterize specific failure modes based on the physics and mechanics of the failure phenomena are used in a prescribed probabilistic structure to generate a failure probability distribution that is modified by test and flight experience in a Bayesian statistical procedure. The probabilistic structure and statistical methodology are generally applicable to any failure mode for which quantitative engineering analysis can be employed to characterize the failure phenomenon and are particularly well suited for use under the constraints on information availability that are typical of such spaceflight systems as the Space Shuttle and planetary spacecraft.
Susceptibility of healthy astronauts to orthostatic hypotension and presyncope is exacerbated upon return from spaceflight. The effect of altered gravity during space flight and planetary transition on human cardiovascular function is of critical importance to maintenance of astronaut health and safety. Hypovolemia, reduced plasma volume, is suspected to play an important role in cardiovascular deconditioning following exposure to spaceflight, which may lead to increased peripheral resistance, attenuated arterial baroreflex, and changes in cardiac function. A promising countermeasure for post-flight orthostatic intolerance is fluid loading used to restore lost plasma volume by giving crew salt tablets and water prior to re-entry. The main purpose of the proposed study is to define the temporal profile of cardiac responses to simulated 0-G conditions before and following a fluid loading countermeasure. 8 men and 8 women will be tested during 4 hour exposures at 6o head down tilt (HDT). Each subject will be given two exposures to HDT on separate days, one with and one without fluid loading (one liter of 0.9% saline solution). Stand tests (orthostatic stress) will be done before and after each HDT. Cardiac measures will be obtained with both impedance cardiography and echo ultrasound