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Electron irradiation from 20 keV to 1 MeV used to study effects on polyethylene terephthalate capacitor-type meteoroid detector
Analysis of bonding and grounding measures for minimizing hazards from electrical fault, lightning, explosion, and electromagnetic radiation atKSC - Vol. 1
For space missions of future, completely autonomous robotic machines will be required to free astronauts from routine chores of equipment maintenance, servicing of faulty systems, etc. and to extend human capabilities in hazardous environments full of cosmic and other harmful radiations. In places of high radiation and uncontrollable ambient illuminations, T.V. camera based vision systems cannot work effectively. However, a vision system utilizing directly measured range information with a time of flight laser rangefinder, can successfully operate under these environments. Such a system will be independent of proper illumination conditions and the interfering effects of intense radiation of all kinds will be eliminated by the tuned input of the laser instrument. Processing the range data according to certain decision, stochastic estimation and heuristic schemes, the laser based vision system will recognize known objects and thus provide sufficient information to the robot's control system which can develop strategies for various objectives.
The design of space-station configurations is influenced by many factors. Probably the most demanding and critical are the biomedical and external hazards requirements imposed to provide the proper environment and supporting facilities for the crew and the adequate protective measures necessary to provide a configuration'in which the crew can live and work efficiently in relative comfort and safety. The major biomedical factors, such as physiology, psychology, nutrition, personal hygiene, waste management, and recreation, all impose their own peculiar requirements. The commonality and integration of these requirements demand the utmost ingenuity and inventiveness be exercised in order to achieve effective configuration compliance. The relationship of biomedical factors for the internal space-station environment will be explored with respect to internal atmospheric constituency, atmospheric pressure levels, oxygen positive pressure, temperature, humidity, CO2 concentration, and atmospheric contamination. The range of these various parameters and the recommended levels for design use will be analyzed. Requirements and criteria for specific problem areas such as zero and artificial gravity and crew private quarters will be reviewed and the impact on the design of representative solutions will be presented. In the areas of external hazards, the impact of factors such as meteoroids, radiation, vacuum, temperature extremes, and cycling on station design will be evaluated. Considerations with respect to operational effectiveness and crew safety will be discussed. The impact of such factors on spacecraft design to achieve acceptable launch and reentry g levels, crew rotation intervals, etc., will be reviewed.
The design of space-station configurations is influenced by many factors, Probably the most demanding and critical are the biomedical and external hazards requirements imposed to provide the proper environment and supporting facilities for the crew and the adequate protective measures necessary to provide a configuration in which the crew can live and work efficiently in relative comfort and safety. The major biomedical factors, such as physiology, psychology, nutrition, personal hygiene, waste management, and recreation, all impose their own peculiar requirements. The commonality and integration of these requirements demand the utmost ingenuity and inventiveness be exercised in order to achieve effective configuration compliance. The relationship of biomedical factors for the internal space-station environment will be explored with respect to internal atmospheric constituency, atmospheric pressure levels, oxygen positive pressure, temperature, humidity, CO2 concentration, and atmospheric contamination. The range of these various parameters and the recommended levels for design use will be analyzed. Requirements and criteria for specific problem areas such as zero and artificial gravity and crew private quarters will be reviewed and the impact on the design of representative solutions will be presented. In the areas of external hazards, the impact of factors such as meteoroids, radiation, vacuum, temperature extremes, and cycling on station design will be evaluated. Considerations with respect to operational effectiveness and crew safety will be discussed. The impact of such factors on spacecraft design to achieve acceptable launch and reentry g levels, crew rotation intervals, etc., will be reviewed. Examples of configurations, subsystems, and internal a arrangement and installations to comply with such biomedical factor requirements will ber presented. The effects of solutions to certain biomedical factors on configuration weight, operational convenience, and program costs will be compared.
Soybeans were chosen for hmar and planetary missions due to their nutritive value and ability to produce oil and protein for further food applications. However, soybeans must be processed into foods prior to crew consumption. Wilson et al. (2003) raised questions about (1) the influence of radiation (on germination and functional properties) that the soybeans would be exposed to during bulk storage for a Mars mission, and (2) the impact of using hydroponically grown versus field grown soybeans on the yield and quality of soyfoods. The influence of radiation can be broken down into two components: (A) affect of surface pasteurization to ensure the astronauts safety from food-borne illnesses (a Hazard Analysis Critical Control Point), and (B) affect of the amount of radiation the soybeans receive during a Mars mission. Decreases in the amount of natural antioxidants and free radical formation and oxidation induced changes in the soybean (lipid, protein, etc.) will influence the nutritional value, texture, quality, and safety of soyfoods made from them. The objectives of this project are to (1) evaluate the influence of gamma and electron beam radiation on bulk soybeans (HACCP, CCP) on the microbial load, germination, ease of processing, and quality of soymilk and tofu; (2) provide scale up and mass balance data for Advanced Life Support subsystems including Biomass, Solid Waste Processing, and Water Recovery Systems; and (3) to compare Hoyt field grown to hydroponically grown Hoyt soybeans for soymilk and tofu production. The soybean cultivar Hoyt, a small standing, high protein cultivar that could grow hydroponically in the AIMS facility on Mars) was evaluated for the production of soymilk and tofu. The quality and yield of the soymilk and tofu from hydroponic Hoyt, was compared to Vinton 81 (a soyfood industry standard), field Hoyt, IA 2032LS (lipoxygenase-free), and Proto (high protein and antioxidant potential). Soymilk and tofu were produced using the Japanese method. The soymilk was coagulated with calcium sulfate dihydrate. Soybeans and tofu were evaluated using chemical, microbial, and instrumental sensory methods. The surface radiation of whole dry soybeans using electron beam or gamma rays at 10 or 30 kGy did provide microbial safety for the astronauts. However, these doses caused oxidative changes that resulted in tofu with rancid aroma, darkening of the tofu, lower tofu yields, more solid waste, and loss of the ability of the seeds to germinate. While lower doses may reduce these problems, we lose the ability to insure microbial safety (cross-contamination) of bulk soybeans for the astronauts. Counter measures could include vacuum packaging, radiating under freezing conditions. A No Effect Dose for food quality, below 10 kGy needs to be determined. Better estimates of the radiation that the food will be exposed to need to determined and shared. Appropriate shielding for the food as well as the astronauts needs to be developed. The Hoyt soybean did not provide a high yielding, high quality tofu. A new small scale system for evaluating soybeans was developed using 50 g quantities of soybeans.
A proposed wireless-communication and data-processing system would exploit recent advances in radio-frequency identification devices (RFIDs) and software to establish information lifelines between firefighters in a burning building and a fire chief at a control station near but outside the building. The system would enable identification of trails that firefighters and others could follow to escape from the building, including identification of new trails should previously established trails become blocked. The system would include a transceiver unit and a computer at the control station, portable transceiver units carried by the firefighters in the building, and RFID tags that the firefighters would place at multiple locations as they move into and through the building (see figure). Each RFID tag, having a size of the order of a few centimeters, would include at least standard RFID circuitry and possibly sensors for measuring such other relevant environmental parameters as temperature, levels of light and sound, concentration of oxygen, concentrations of hazardous chemicals in smoke, and/or levels of nuclear radiation. The RFID tags would be activated and interrogated by the firefighters and control-station transceivers. Preferably, RFID tags would be configured to communicate with each other and with the firefighters units and the control station in an ordered sequence, with built-in redundancy. In a typical scenario, as firefighters moved through a building, they would scatter many RFID tags into smoke-obscured areas by use of a compressed-air gun. Alternatively or in addition, they would mark escape trails by dropping RFID tags at such points of interest as mantraps, hot spots, and trail waypoints. The RFID tags could be of different types, operating at different frequencies to identify their functions, and possibly responding by emitting audible beeps when activated by signals transmitted by transceiver units carried by nearby firefighters.
Solar arrays in space are subjected to a daunting set of environmental hazards, including extreme temperature cycles, particulate and ultraviolet radiation in space, micrometeoroid damage, and exposure to a flux of atomic oxygen in low-Earth orbit. Over the years since the first solar cells were sent into space on Vanguard 1 in 1958, space solar array technology has advanced to develop photovoltaic materials, cells, and arrays resistant to these degradation mechanisms. This chapter highlights approaches to solar array design for near-Sun missions including thermal management at the systems level, to optimize efficiency at elevated temperature, or the use of novel device design to reduce the incident solar energy to limit operating temperature. Several of these have been successfully demonstrated to enable solar-powered spacecraft to explore the near-Sun planets such as Mercury and Venus as well as the Sun itself.
The major health hazards of spaceflight include higher levels of damaging radiation, altered gravity, extended periods of isolation and confinement, a closed and potentially hostile living environment, and the stress associated with being a long distance from Earth. As we increase the duration of lunar stays with foreseeable communication latencies and disruptions, there will be a progressive need for crew to maintain their own health and independently respond to critical medical events. The Exploration Medical Capability element of the NASA Human Research Program is developing a set of Medical System requirements for lunar transit and surface operations. These requirements specify the capabilities, processes and procedures of a habitat Medical System needed for a range of conditions known to occur during spaceflight. Requirement text is written so as not to constrain innovative design solutions necessary for a resilient system. The requirement set includes attributes and functions the Medical System imposes on eight additional habitat systems. A key property of the Medical System is the provision of medical knowledge that will be stored, updated, analyzed, and secured within a Habitat Data System. A Task Performance Support System will aid in medical data acquisition and interpretation, crew training, medical condition prevention, diagnosis and treatment, provide interactive procedures, and track medical inventory. A Wellness System will focus on the provision of countermeasures to prevent, mitigate or treat adverse physical and behavioral health effects while the Medical System recommends adjustments to these countermeasures to maintain crew health. An Environmental Monitoring System will share out-of-bounds readings of air and water quality, acoustics, and radiation exposure levels with the Medical System to help identify issues before they affect crew health and performance. A Communications System will provide secured and private consultations between crew and the ground medical team and their loved ones on Earth. The Medical System also imposes requirements on a Research & Testbed System, fostering advanced medical science such as human research. A Waste Management System provides biohazard waste containment and waste disposal options (recycle and reuse). An Extravehicular Activity System supports crew health during lunar surface activities. And finally, a Maintenance Support System ensures that medical equipment is performing as expected. These requirements are being specifically developed for lunar surface operations but could help to identify Medical System requirements for any space habitat (e.g., I-Hab, commercial endeavors, etc.).
Europa, the smallest of Jupiter’s Galilean moons, is thought to harbor a vast liquid water ocean beneath its icy crust, making it one of the most scientifically intriguing targets for a robotic surface sampling mission in our Solar System. However, autonomously landing a spacecraft safely and precisely on Europa poses unique challenges, such as very little existing high-resolution reconnaissance imagery, a surface expected to be very rough and hazardous over a wide range of scales, an extremely intense ionizing radiation environment, and very limited lander resources for mass and volume. To address these challenges, we propose a novel Intelligent Landing System (ILS) combining four Guidance, Navigation & Control (GN&C) sensing functions – velocimetry, altimetry, map-relative localization, and hazard detection – that would together enable safe and precise landing on Europa’s surface. The ILS is a smart sensor system, combining an inertial measurement unit (IMU), a monocular, passive-optical camera, and a light detection and ranging (Li-DAR) sensor with dedicated computing resources as well as an onboard 3D terrain map. The ILS leverages more than a decade of technology development from programs such as the Lander Vision System, currently baselined on the Mars 2020 mission. This paper provides a detailed description of the proposed ILS architecture and concept of operations, as well as select preliminary simulation results to assess performance and robustness.
NASA’s Artemis program plans to have a sustainable lunar base deployed on the Moon by 2028. The base calls for a foundation surface habitat that can support a crew of four members for a minimum mission duration of 28-days. The lack of a magnetic field and significant lunar atmosphere extends the lifetime of secondary radiation emitted from metallic structures, which is a health hazard for exposed astronauts. Integration of non-metallic structural materials into surface habitat design may alleviate some of these concerns. Additionally, it is favorable for the structure to be collapsible for transportation to optimize payload volume, mass efficiency, and monetary constraints. As a result, inflatable structures are being investigated due to their improved packing efficiency at launch, optimal mass-to-volume ratio, and large surface area that can efficiently disperse structural loads and heat. Currently, only two inflatable airlocks have been deployed in space. Thus, there is a significant need to advance technologies associated with inflatable structures to provide greater options for future missions, i.e., Artemis and beyond. This study focused on the inflatable lunar habitat applications of emerging NASA Langley Research Center (LaRC) technologies and their required development steps to become space qualified. The Bowling Habitat architecture was generated from 13 of these NASA LaRC technologies, five of which were deemed critical, five determined as enhancing technologies, and three were classified as transformational technologies for the Artemis program. To address the payload constraints, the study also considered a tentative timeline that aligned with the current Artemis schedule for transporting the Bowling Habitat to the Moon. Ultimately, the Bowling Habitat mainly addressed the structural needs of an inflatable lunar habitat, meaning that major areas pertaining to the life-style aspects of the habitat must be improved. Areas include, but are not limited to, hard connection points, the monitoring of human health, and extra radiation protection for solar proton events.
Attention is given the hazards posed to Space Shuttle crews by energetic proton radiation from inherently unpredictable solar flares, such as that of April 10-13, 1981, which was experienced by the Space Shuttle Columbia. The most energetic protons from this flare reached the earth's atmosphere an hour after flare onset, and would have posed a potentially lethal threat to astronauts engaged in extravehicular activity in a polar or geosynchronous orbit rather than the low-latitude, low-altitude orbit of this mission. It is shown that proton-producing flares are associated with energization in shocks, many of which are driven by coronal mass ejections. Insights gained from the Solar Maximum Year programs allow reconsideration of proton shower forecasting, which will be essential in the prediction of the weather that Space Shuttle astronauts will encounter during extravehicular activities.
The LEO environment and its effects on thermal-control materials (TCMs) being evaluated for use in long-term-mission space structures such as the Space Station are characterized, summarizing the results of recent space and laboratory experiments. Factors examined include atomic oxygen (a serious problem out to 600-700 km), ionizing radiation, solar UV radiation, solid particles (manmade debris and micrometeoroids, a significant hazard out to about 1000 km), and synergistic effects. Numerical data on the expected intensity of these effects for the different Space Station components, the resistance of specific TCMs to the effects, and the effectiveness of protective coatings are compiled in extensive tables and illustrated with diagrams, graphs, and micrographs.
The Space Radiation Health Program (SRHP) is defined in terms of motivation and methodology with specific reference given to the impacts of HZE particles and solar energetic particles. The biological hazards are mentioned that can be associated with the two particle types and ionizing radiation in general. The lack of data on the impact of such radiation and effective shielding countermeasures is identified as the primary motivation for worst-case assumptions. However, the resulting shielding designs can potentially overestimate the thickness by a factor of 10 and add unnecessarily to vehicle take-off mass. A space-based validation system is proposed to complement ground-based investigations of the effects of ionizing radiation in interplanetary space. The Lifesat satellite is proposed as a part of the SRHP effort to determine the requirements for protection and future shielding specifications.
Varied mission life and complexity is growing for small spacecraft. Small missions benefit from detailed hazard definition and evaluation as done in the past. Requirements need to flow from the system down to the parts level and aid system level radiation tolerance. RHA is highlighted with increasing COTS usage.
The phenomenon of high ice water content (HIWC) occurs in mesoscale convective systems (MCSs) when a large number of small ice particles with typical sizes of a few hundred micrometers, concentrations of the order of 10 2 –10 3 L −1 , and IWC exceeding 1 g m −3 are present at high altitudes. HIWC regions in MCSs may extend vertically up to 10 km above the melting layer and horizontally up to hundreds of kilometers, filling large volumes of the convective systems. HIWC has great geophysical significance due to its effect on precipitation formation, the hydrological cycle, and the radiative properties of MCSs. It is also recognized as a hazard for commercial aviation operations since it can result in engine power loss and in the malfunctioning of aircraft data probes. This study summarizes observational and numerical simulation efforts leading to the development of a conceptual model for the production of HIWC in tropical MCSs based on the data collected during the HAIC–HIWC campaign. It is hypothesized that secondary ice production (SIP) in the vicinity of the melting layer plays a key role in the formation and sustainability of HIWC. In situ observations suggest that the major SIP mechanism in the vicinity of the melting layer is related to the fragmentation of freezing drops (FFDs). Both in situ data and numerical simulations suggest that the recirculation of drops through the melting layer led to the amplification of SIP. The proposed conceptual model and simulation results motivate further efforts to extend reproducible laboratory measurements.
This brief abstract reviews the development of the current day approach to human system risk management for space flight and the development of the critical components of this process over the past few years. The human system risk management process now provides a comprehensive assessment of each human system risk by design reference mission (DRM) and is evaluated not only for mission success but also for long‐term health impacts for the astronauts. The discipline of bioastronautics is the study of the biological and medical effects of space flight on humans. In 1997, the Space Life Sciences Directorate (SLSD) initiated the Bioastronautics Roadmap (Roadmap) as the "Critical Path Roadmap", and in 1998 participation in the roadmap was expanded to include the National Space Biomedical Research Institute (NSBRI) and the external community. A total of 55 risks and 250 questions were identified and prioritized and in 2000, the Roadmap was base-lined and put under configuration control. The Roadmap took into account several major advisory committee reviews including the Institute of Medicine (IOM) "Safe Passage: Astronaut care for Exploration Missions", 2001. Subsequently, three collaborating organizations at NASA HQ (Chief Health and Medical Officer, Office of Space Flight and Office of Biological & Physical Research), published the Bioastronautics Strategy in 2003, that identified the human as a "critical subsystem of space flight" and noted that "tolerance limits and safe operating bands must be established" to enable human space flight. These offices also requested a review by the IOM of the Roadmap and that review was published in October 2005 as "A Risk Reduction Strategy for Human Exploration of Space: A Review of NASA's Bioastronautics Roadmap", that noted several strengths and weaknesses of the Roadmap and made several recommendations. In parallel with the development of the Roadmap, the Office of the Chief Health and Medical Officer (OCHMO) began a process in 2004 of evaluating the tolerance limits and safe operating bands called for in the Bioastronautics Strategy. Over the next several years, the concept of the "operating bands" were turned into Space Flight Human System Standards (SFHSS), developed by the technical resources of the SLSD at the NASA Johnson Space Center (JSC). These standards were developed and reviewed at the SLSD and then presented to the OCHMO for acceptance. The first set of standards was published in 2007 as the NASA‐STD‐3001, Volume 1, Crew Health that elaborated standards for several physiological areas such as cardiovascular, musculoskeletal, radiation exposure and nutrition. Volume 2, Human Factors, Habitability and Human Health was published in 2011, along with development guidance in the Human Integration Design Handbook (HIDH). Taken together, the SFHSS Volumes 1 and 2, and the HIDH replaced the NASA‐STD‐3000 with new standards and revisions of the older document. Three other changes were also taking place that facilitated the development of the human system risk management approach. In 2005, the life sciences research and development portfolio underwent a comprehensive review through the Exploration Systems Architecture Study (ESAS) that resulted in the reformulation of the Bioastronautics Program into Human Research Program (HRP) that was focused on appropriate mitigation results for high priority human health risks. The baseline HRP budget was established in August 2005. In addition, the OCHMO formulated the Health and Medical Technical Authority (HMTA) in 2006 that established the position of the Chief Medical Officer (CMO) at the NASA JSC along with other key technical disciplines, and the OCHMO became the responsible office for the SFHSS as noted above. The final change was the establishment in 2008 of the Human System Risk Board (HSRB), chaired by the CMO with representation from the HRP, SLSD management and technical experts. The HSRB then began to review all human system risks, established a comprehensive risk management and configuration management plan and data sharing policy. These major developments of standards, the HRP, the HMTA and a forum for review of human system risks (HSRB) facilitated the integration of human research, medical operations, systems engineering and many other disciplines in the comprehensive review of human system risks. The HSRB began a comprehensive review of all potential inflight medical conditions and events and over the course of several reviews consolidated the number of human system risks to 30 where the greatest emphasis is placed for investing program dollars for risk mitigation. The HSRB considers all available evidence from human research, medical operations and occupational surveillance in assessing the risks for appropriate mitigation and future work. All applicable DRMs (low earth orbit 6 and 12 months, deep space sortie for 30 days and 1 year, a one year lunar mission, and a planetary mission for 3 years) are considered as human system risks are modified by the hazards associated with space flight such as microgravity, exposure to radiation, distance from the earth, isolation and a closed environment. Each risk has a summary assessment representing the state of knowledge/evidence base for that risk, the available risk mitigations, traceability to the SFHSS and program requirements, and future work required. These data then can drive coordinated budgets across the HRP, the International Space Station, Crew Health and Safety and Advanced Exploration System budgets. These risk assessments were completed for 6 DRMs in December of 2014 and serve as the baseline for which subsequent research and technology development and crew health care portfolios can be assessed. The HSRB will review each risk at least annually and especially when new information is available that must be considered for effective risk mitigation. The current status of each risk can be reported to program management for operations, budget reviews and general oversight of the human system risk management program.
The importance of long-range planning for space flight emergency systems is pointed out. Factors in emergency systems planning are considered, giving attention to some of the mission classes which have to be taken into account. Examples of the hazards in space flight include fire, decompression, mechanical structure failures, radiation, collision, and meteoroid penetration. The criteria for rescue vehicles are examined together with aspects regarding the conduction of rescue missions. Future space flight programs are discussed, taking into consideration low earth orbit space stations, geosynchronous orbit space stations, lunar operations, manned planetary missions, future space flight vehicles, the space shuttle, special purpose space vehicles, and a reusable nuclear shuttle.