Life support systems for extravehicular activity
Gemini life support systems for extravehicular missions
Burns, F. T.↗
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HL-20 operations and support requirements for the Personnel Launch System mission
The processing, mission planning, and support requirements were defined for the HL-20 lifting-body configuration that can serve as a Personnel Launch System. These requirements were based on the assumption of an operating environment that incorporates aircraft and airline support methods and techniques that are applicable to operations. The study covered the complete turnaround process for the HL-20, including landing through launch, and mission operations, but did not address the support requirements of the launch vehicle except for the integrated activities. Support is defined in terms of manpower, staffing levels, facilities, ground support equipment, maintenance/sparing requirements, and turnaround processing time. Support results were drawn from two contracted studies, plus an in-house analysis used to define the maintenance manpower. The results of the contracted studies were used as the basis for a stochastic simulation of the support environment to determine the sufficiency of support and the effect of variance on vehicle processing. Results indicate the levels of support defined for the HL-20 through this process to be sufficient to achieve the desired flight rate of eight flights per year.
Morris, W. D.↗
High Energy Physics Network Requirements Review: Two-Year Update
The Energy Sciences Network (ESnet) is the high-performance network user facility for the US Department of Energy (DOE) Office of Science (SC) and delivers highly reliable data transport capabilities optimized for the requirements of data-intensive science. In essence, ESnet is the circulatory system that enables the DOE science mission by connecting all its laboratories and facilities in the US and abroad. ESnet is funded and stewarded by the Advanced Scientific Computing Research (ASCR) program and managed and operated by the Scientific Networking Division at Lawrence Berkeley National Laboratory (LBNL). ESnet is widely regarded as a global leader in the research and education networking community. ESnet interconnects DOE national laboratories, user facilities, and major experiments so that scientists can use remote instruments and computing resources as well as share data with collaborators, transfer large datasets, and access distributed data repositories. ESnet is specifically built to provide a range of network services tailored to meet the unique requirements of the DOE’s data-intensive science. In July 2023, the Energy Sciences Network (ESnet) and the High Energy Physics program (HEP) of the DOE SC organized an interim ESnet requirements review of HEP-supported activities, to follow up on the work started during the 2020 HEP Network Requirements Review. Preparation for these events included checking back with the key stakeholders: program and facility management, research groups, and technology providers. Each stakeholder group was asked to prepare updates to their previously submitted case study documents, so that ESnet could update the understanding of any changes to the current, near-term, and long-term status, expectations, and processes that will support the science activities of the program.
97 MATHEMATICS AND COMPUTING↗
Advanced Software Development Workstation Project
The Advanced Software Development Workstation Project, funded by Johnson Space Center, is investigating knowledge-based techniques for software reuse in NASA software development projects. Two prototypes have been demonstrated and a third is now in development. The approach is to build a foundation that provides passive reuse support, add a layer that uses domain-independent programming knowledge, add a layer that supports the acquisition of domain-specific programming knowledge to provide active support, and enhance maintainability and modifiability through an object-oriented approach. The development of new application software would use specification-by-reformulation, based on a cognitive theory of retrieval from very long-term memory in humans, and using an Ada code library and an object base. Current tasks include enhancements to the knowledge representation of Ada packages and abstract data types, extensions to support Ada package instantiation knowledge acquisition, integration with Ada compilers and relational databases, enhancements to the graphical user interface, and demonstration of the system with a NASA contractor-developed trajectory simulation package. Future work will focus on investigating issues involving scale-up and integration.
Lee, Daniel↗
Hints of Habitable Environments on Mars Challenge Our Studies of Mars-Analog Sites on Earth
Life as we know it requires water with a chemical activity (alpha) >or approx.0.6 and sources of nutrients and useful energy. Some biota can survive even if favorable conditions occur only intermittently, but the minimum required frequency of occurrences is poorly understood. Recent discoveries have vindicated the Mars exploration strategy to follow the water. Mars Global Surveyor s Thermal Emission Spectrometer (TES) found coarse-grained hematite at Meridiani Planum. Opportunity rover confirmed this and also found evidence of ancient sulfate-rich playa lakes and near-surface groundwater. Elsewhere, TES found evidence of evaporitic halides in topographic depressions. But alpha might not have approached 0.6 in these evaporitic sulfate- and halide-bearing waters. Mars Express (MEX) and Mars Reconnaissance Orbiter (MRO) found extensive sulfate evaporites in Meridiani and Valles Marineris. MEX found phyllosilicates at several sites, most notably Mawrth Valles and Nili Fossae. MRO's CRISM near-IR mapper extended the known diversity and geographic distribution of phyllosilicates to include numerous Noachian craters. Phyllosilicates typically occur at the base of exposed ancient rock sections or in sediments in early Hesperian craters. It is uncertain whether the phyllosilicates developed in surface or subsurface aqueous environments and how long aqueous conditions persisted. Spirit rover found remarkably pure ferric sulfate, indicating oxidation and transport of Fe and S, perhaps in fumaroles or hot springs. Spirit also found opaline silica, consistent with hydrothermal activity. CRISM mapped extensive silica deposits in the Valles Marineris region, consistent with aqueous weathering and deposition. CRISM also found ultramafic rocks and magnesite at Nili Fossae, consistent with serpentinization, a process that can sustain habitable environments on Earth. The report of atmospheric methane implies subsurface aqueous conditions. A working hypothesis is that aqueous environments persisted in the near-subsurface for hundreds of millions of years and might exist even today. Studies of Mars-analog environments must better understand subsurface nonphotosynthetic ecosystems and their biosignatures in mafic and ultramafic terranes. Studies must determine minimum needs for water activity and energy and also establish survival limits when conditions that support active metabolism and propagation become progressively less frequent over time.
desMarais, David J↗
Latent transforming growth factor beta1 activation in situ: quantitative and functional evidence after low-dose gamma-irradiation
The biological activity of transforming growth factor beta1 (TGF-beta) is controlled by its secretion as a latent complex in which it is noncovalently associated with latency-associated peptide (LAP). Activation is the extracellular process in which TGF-beta is released from LAP, and is considered to be a primary regulatory control. We recently reported rapid and persistent changes in TGF-beta immunoreactivity in conjunction with extracellular matrix remodeling in gamma-irradiated mouse mammary gland. Our hypothesis is that these specific changes in immunoreactivity are indicative of latent TGF-beta activation. In the present study, we determined the radiation dose response and tested whether a functional relationship exists between radiation-induced TGF-beta and collagen type III remodeling. After radiation exposures as low as 0.1 Gy, we detected increased TGF-beta immunoreactivity in the mammary epithelium concomitant with decreased LAP immunostaining, which are events consistent with activation. Quantitative image analysis demonstrated a significant (P=0.0005) response at 0.1 Gy without an apparent threshold and a linear dose response to 5 Gy. However, in the adipose stroma, loss of LAP demonstrated a qualitative threshold at 0.5 Gy. Loss of LAP paralleled induction of collagen III immunoreactivity in this tissue compartment. We tested whether TGF-beta mediates collagen III expression by treating animals with TGF-beta panspecific monoclonal antibody, 1D11.16, administered i.p. shortly before irradiation. Radiation-induced collagen III staining in the adipose stroma was blocked in an antibody dose-dependent manner, which persisted through 7 days postirradiation. RNase protection assay revealed that radiation-induced elevation of total gland collagen III mRNA was also blocked by neutralizing antibody treatment. These data provide functional confirmation of the hypothesis that radiation exposure leads to latent TGF-beta activation, support our interpretation of the reciprocal shift in immunoreactivity as evidence of activation, and implicate TGF-beta as a mediator of tissue response to ionizing radiation. The sensitivity of activation to low radiation doses points to a potential role for TGF-beta in orchestrating tissue response to oxidative stress. As such, radiation may be useful as a probe to delineate the consequences of latent TGF-beta activation in situ.
NASA Discipline Radiation Health↗
Athena in 2013 and Beyond
TRISA, the U.S. Army TRADOC G2 Intelligence Support Activity, received Athena 1 in 2009. They first used Athena 3 to support studies in 2011. This paper describes Athena 4, which they started using in October 2012. A final section discusses issues that are being considered for incorporation into Athena 5 and later. Athena's objective is to help skilled intelligence analysts anticipate the likely consequences of complex courses of action that use our country's entire power base, not just our military capabilities, for operations in troubled regions of the world. Measures of effectiveness emphasize who is in control and the effects of our actions on the attitudes and well-being of civilians. The planning horizon encompasses not weeks or months, but years. Athena is a scalable, laptop-based simulation with weekly resolution. Up to three months of simulated time can pass between game turns that require user interaction. Athena's geographic scope is nominally a country, but can be a region within a county. Geographic resolution is "neighborhoods", which are defined by the user and may be actual neighborhoods, provinces, or anything in between. Models encompass phenomena whose effects are expected to be relevant over a medium-term planning horizon-three months to three years. The scope and intrinsic complexity of the problem dictate a spiral development process. That is, the model is used during development and lessons learned are used to improve the model. Even more important is that while every version must consider the "big picture" at some level of detail, development priority is given to those issues that are most relevant to currently anticipated studies. For example, models of the delivery and effectiveness of information operations messaging were among the additions in Athena 4.
Chamberlain, Robert G.↗
Athena in 2013 and Beyond
TRISA, the U.S. Army TRADOC G2 Intelligence Support Activity, received Athena 1 in 2009. They first used Athena 3 to support studies in 2011. This paper describes Athena 4, which they started using in October 2012. A final section discusses issues that are being considered for incorporation into Athena 5 and later. Athena's objective is to help skilled intelligence analysts anticipate the likely consequences of complex courses of action that use our country's entire power base, not just our military capabilities, for operations in troubled regions of the world. Measures of effectiveness emphasize who is in control and the effects of our actions on the attitudes and well being of civilians. The planning horizon encompasses not weeks or months, but years.Athena is a scalable, laptop-based simulation with weekly resolution. Up to three months of simulated time can pass between game turns that require user interaction. Athena's geographic scope is nominally a country, but can be a region within a county. Geographic resolution is "neighborhoods", which are defined by the user and may be actual neighborhoods, provinces, or anything in between. Models encompass phenomena whose effects are expected to be relevant over a medium-term planning horizon--three months to three years.The scope and intrinsic complexity of the problem dictate a spiral development process. That is, the model is used during development and lessons learned are used to improve the model. Even more important is that while every version must consider the "big picture" at some level of detail, development priority is given to those issues that are most relevant to currently anticipated studies. For example, models of the delivery and effectiveness of information operations messaging were among the additions in Athena 4.
Diplomatic, Informational, Military, Economic (DIM↗
ESGF project plan for ramping down development activities and transition the project and data to a new team
This document summarizes the current software development activities carried by the ESGF team with planned delivery dates before the transition of the project to a new team. The work we started on the publishing, search and retrieval, and the backend for indexing and data management that can be deployed using Kubernetes are planned to be delivered within the next three months; however, this assumes that the current team members will continue to work on the project. The activities are listed in Table 1 by priority and in case we lose team members, development of lower priority tasks can be paused and passed to the new team with its current status. Team members can be re-assigned based on their availability and transition work needed. Table 2 below describe activities necessary to help project transition to the new team. Deadlines for these activities are before October 1 st of 2022 or the completion of a successful transition. Support during the transition period assumes that we will have 3 key ESGF members and the ESGF PI supported at the 50% level or less for the duration of the transition. The level of support is an estimate, and it depends on several factors that cannot be decided at this time. The total cost of the proposed work and support activities for fiscal year 2021 is $1,270K with $230K carry over to fiscal year 2022. The cost for the support work listed in Table 2 is the sum of the two rows “HW support” and “project support, maintenance, and transition efforts”, colored blue, in Table1 which adds up to $720K. This cost is included in the $1,270K cost in table 1.
97 MATHEMATICS AND COMPUTING↗
Knowledge-based simulation
An architecture for a knowledge-based simulator is described. The task of scheduling represents an area in which such a tool might be applied. More specifically, scheduling for crew and ground support activities for the shuttle and space station would benefit from the application of knowledge-based simulation. The knowledge-based simulator would allow the crew and support personnel to schedule and reschedule activities in a timely and flexible manner in order to examine and test possible plans.
Newman, P. A.↗
NASA Environmental Control and Life Support Technology Development for Exploration: 2021 to 2022 Overview
Over the past year, significant progress has occurred in technology development, ground testing, and ISS technology demonstrations within the NASA Environmental Control and Life Support (ECLSS) community. This paper provides a technology development update in the following capability areas: life support, environmental monitoring, fire safety, and logistics. Technologies for exploration missions must be reliable in their operation which support crewed mission phases. However, they also need to be put into a reduced use or dormant states to support uncrewed mission phases and then successfully and reliably returned to a nominal state to support crew. Multi-year demonstration of systems operation across this range of conditions are essential to mission success. Project overviews will include how the current activity supports the goal of multi-year demonstrations, planned follow-on activities, and what type of exploration mission elements are targeted for infusion. Technologies must be demonstrated and validated early enough to inform early exploration element milestone reviews (mission concept reviews, systems requirement reviews and no later than preliminary design reviews) so that supporting vehicle systems can also be matured. Consequently, for low technology readiness activities, it is important to also identify which mission elements they might infuse into and how they may offer potential operational, dormancy, or mass benefits. While low TRL technology timelines may not support initial mission needs, early infusion is still reasonable with sufficient testing to validate performance and reliability.
Life Support↗
National and Regional Initiatives to Promote Energy Efficiency and Renewable Energy Through State Energy Offices
The National Association of State Energy Officials (NASEO) worked with the U.S. Department of Energy’s (DOE) Office of Energy Efficiency and Renewable Energy (EERE), Weatherization and Intergovernmental Programs Office (WIP) over a ten year period to provide technical assistance, research and analyses, and enhanced coordination between DOE and the State and Territory Energy Offices. Over the life of the agreement, NASEO worked with WIP and the states to provide statewide strategic energy plan analyses and recommendations, including customized technical assistance to the states; peer to peer financing assistance via NASEO’s Financing Committee and supporting activities; training on core energy policies and programs, including dialogues and resources to support energy-air coordination, a training for new State Energy Office Directors, peer to peer exchange via a rural energy taskforce, and support to states to enhance buildings efficiency, home energy labeling, and technology deployment opportunities; support for State Energy Program metrics; and regional coordination via regional coordinators and peer exchange opportunities both in-person and online. Over the life of the project, the position and role of State Energy Offices within state government has changed, with now 80 percent of State Energy Office Directors serving as their Governor’s energy advisor, or reporting directly to their Governor’s energy advisor. This shift in stature has made it ever more crucial for State Energy Offices to receive timely and relevant technical assistance across a range of energy issue areas. NASEO, in collaboration with WIP, was able to deliver this technical assistance, and energy efficiency and renewable energy deployment has accelerated across the country. The State Energy Office Directors and their staff continue to engage in NASEO’s Committees – many of which were supported through this agreement – and have provided formal and informal feedback on the value of the programs supported through this award (e.g., reporting via survey increased understanding of their roles and technical assistance offerings provided by WIP and NASEO following the New Director Trainings). Moreover, resources developed through this award (e.g., Comprehensive State Energy Planning Guidelines, State Energy Loan Fund Database, Rural Data Resources for State Energy Planning and Programs, The Value of Adding home Energy Score to Low-Income Energy Efficiency Programs, etc.) have been cited by states as instrumental to their understanding of specific energy issue areas and in many cases led directly to enhanced program design within a state (e.g. Iowa citing their review of NASEO’s Comprehensive State Energy Planning Guidelines as a necessary first step in their planning process, later following may of the steps outlined in the guidelines). The priorities of the states and federal government have evolved over the last decade, with an increasing focus on climate mitigation and adaptation, equity impacts and considerations, energy security and resilience, and enhanced energy efficiency and renewable energy technology deployment, but the roots of these new priorities are based in the state and federal policies and programs, and research and analyses, that were supported in part through this award and other complementary initiatives. NASEO looks forward to continuing to support the states, and collaborate and coordinate with DOE, as we build on this important foundation in the years ahead.
29 ENERGY PLANNING, POLICY, AND ECONOMY↗
Life Sciences Activities Associated with Project Mercury
Fifteen years of speculation and study concerning the problems of placing man into space flight produced a mass of reports which contemplated the hurdles and suggested solutions needed to permit safe flight. The accumulation of problems occurred in all disciplines. This could have been expected because the area of study was in the unknown, and speculation and calculation were the only methods of attack until flight data could be obtained. The Life Sciences community was as prolific in the identification of potential problem areas as the other scientific disciplines. The arrival of the era of manned space flight offers the opportunity to assess the problems directly and to define what is speculation and what is problem. This paper will discuss two areas of life sciences activities during the Project Mercury program. The first area will review the life-support activities associated with the spacecraft development and the provisions for the astronaut. The second area will present a summarization of the data concerning man's ability to live and work in this new environment and will attempt to present an analysis of the significance of the findings in light of future flights.
Physiological response↗
Support of an Active Science Project by a Large Information System: Lessons for the EOS Era
The ability of large information systems to support the changing data requirements of active science projects is being tested in a NASA collaborative study. This paper briefly profiles both the active science project and the large information system involved in this effort and offers some observations about the effectiveness of the project support. This is followed by lessons that are important for those participating in large information systems that need to support active science projects or that make available the valuable data produced by these projects. We learned in this work that it is difficult for a large information system focused on long term data management to satisfy the requirements of an on-going science project. For example, in order to provide the best service, it is important for all information system staff to keep focused on the needs and constraints of the scientists in the development of appropriate services. If the lessons learned in this and other science support experiences are not applied by those involved with large information systems of the EOS (Earth Observing System) era, then the final data products produced by future science projects may not be robust or of high quality, thereby making the conduct of the project science less efficacious and reducing the value of these unique suites of data for future research.
Angelici, Gary L.↗
A general-purpose development environment for intelligent computer-aided training systems
Space station training will be a major task, requiring the creation of large numbers of simulation-based training systems for crew, flight controllers, and ground-based support personnel. Given the long duration of space station missions and the large number of activities supported by the space station, the extension of space shuttle training methods to space station training may prove to be impractical. The application of artificial intelligence technology to simulation training can provide the ability to deliver individualized training to large numbers of personnel in a distributed workstation environment. The principal objective of this project is the creation of a software development environment which can be used to build intelligent training systems for procedural tasks associated with the operation of the space station. Current NASA Johnson Space Center projects and joint projects with other NASA operational centers will result in specific training systems for existing space shuttle crew, ground support personnel, and flight controller tasks. Concurrently with the creation of these systems, a general-purpose development environment for intelligent computer-aided training systems will be built. Such an environment would permit the rapid production, delivery, and evolution of training systems for space station crew, flight controllers, and other support personnel. The widespread use of such systems will serve to preserve task and training expertise, support the training of many personnel in a distributed manner, and ensure the uniformity and verifiability of training experiences. As a result, significant reductions in training costs can be realized while safety and the probability of mission success can be enhanced.
Savely, Robert T.↗
The International Space Station: New Capabilities for Disaster Response and Humanitarian Aid
The International Space Station (ISS) has been acquiring Earth imagery since 2000, primarily in the form of astronaut photography using hand-held film and digital cameras. Recent additions of more sophisticated multispectral and hyperspectral sensor systems have expanded both the capabilities and relevance of the ISS to basic research, applied Earth science, and development of new sensor technologies. Funding opportunities established within NASA, the US National Laboratories and the international partner organizations have generated instrument proposals that will further enhance these capabilities. With both internal and external sensor location options, and the availability of both automated and human-tended operational environments, the ISS is a unique platform within the constellation of Earth-observing satellites currently in orbit. Current progress and challenges associated with development of ISS terrestrial remote sensing capabilities in the area of disaster response and support of relief efforts will be presented. The ISS orbit allows for imaging of the Earth's surface at varying times of day and night, providing opportunities for data collection over approximately 95% of the populated regions. These opportunities are distinct from--yet augment--the data collection windows for the majority of sensors on polar-orbiting satellites. In addition to this potential for "being in the right place at the right time" to collect critical information on an evolving disaster, the presence of a human crew also allows for immediate recognition of an event from orbit, notification of relevant organizations on the ground, and re-tasking of available remote sensing resources to support humanitarian response and relief efforts. Challenges to establishing an integrated response capability are both technical (coordination of sensor targeting and data collection, rapid downlink and posting of data to a central accessible hub, timely generation and distribution of relevant data products) and operational (notification and engagement of sensor support teams, international partner agency sanction of astronaut support activities). To better collaborate on common issues and strengthen applications, including using the data to support disaster response, we established an ISS Program Science Forum Working Group for Earth Observations comprised of representatives from the international partner agencies. This international forum welcomes input and support from relevant United Nations task groups regarding our disaster response and humanitarian aid to enable development of the ISS capabilities in this area for greatest value to the international community.
Stefanov, William↗
Spectroscopic characterization of Mn 2+ and Cd 2+ coordination to phosphorothioates in the conserved A9 metal site of the hammerhead ribozyme
Phosphorothioate modifications have widespread use in the field of nucleic acids. As substitution of sulfur for oxygen can alter metal coordination preferences, the phosphorothioate metal-rescue experiment is a powerful method for identifying metal coordination sites that influence specific properties in a large RNAs. The A9/G10.1 metal binding site of the hammerhead ribozyme (HHRz) has previously been shown to be functionally important through phosphorothioate rescue experiments. While an A9-S Rp substitution is inhibitory in Mg 2+ , thiophilic Cd 2+ rescues HHRz activity. Mn 2+ is also often used in phosphorothioate metal-rescue studies but does not support activity for the A9-S Rp HHRz. Here, we use EPR, electron spin-echo envelope modulation (ESEEM), and X-ray absorption spectroscopic methods to directly probe the structural consequences of Mn 2+ and Cd 2+ coordination to R p and S p phosphorothioate modifications at the A9/G10.1 site in the truncated hammerhead ribozyme (tHHRz). The results demonstrate that while Cd 2+ does indeed bind to S in the thio-substituted ligand, Mn 2+ coordinates to the non–sulfur oxo group of this phosphorothioate, regardless of isomer. Computational models demonstrate the energetic preference of Mn—O over Mn—S coordination in metal-dimethylthiophosphate models. In the case of the tHHRz, the resulting Mn 2+ coordination preference of oxygen in either R p or S p A9 phosphorothioates differentially tunes catalytic activity, with Mn—O coordination in the A9-S Rp phosphorothioate enzyme being inhibitory.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Material Control & Accountancy for Molten Salt Reactors (FY2021 Report)
There is significant domestic and international interest, investment, and research and development momentum to pursue advanced nuclear reactor technologies. Molten salt reactor (MSR) concepts display the largest variability in fuel type and design features among the current advanced concepts. MSRs have been proposed with various core designs, sizes (power), and fuel cycles. Salt-fueled molten salt systems represent the only advanced reactor type with fuel that is not in a solid form during operation. These “liquid-fueled” MSRs are unique from perspectives of fuel fabrication, spent irradiated fuel and waste components, licensing, and material control and accountability (MC&A) including the potential of fissile material holdup. The liquid fuel salt is the defining distinction in comparison to other advanced reactors that propose TRI-structural ISOtropic particle fuel pebbles, various coolant options (e.g., molten salts or metals, high temperature gas), or small modular alternatives using solid fuel variants including both light water reactors and non-light water reactors. MSRs are appealing to the nuclear energy industry because of the diverse reactor characteristics they can support including various neutron energy spectra, fueling requirements, fuel cycles, and/or fuel utilization. However, because of the significant deviation and diversity of a salt-fueled system compared to traditional solid fuel light water-cooled reactors (LWRs), the history, regulatory licensing framework, modeling capabilities, and supporting engineering technology are either lacking or, in some cases, nonexistent. Therefore, the research community is actively supporting advanced MSR development on many of these fronts in particular to assist MSR vendors with licensing requirements. ORNL is leading the research and development of respective MC&A approaches for salt-fueled MSRs. This report summarizes the research performed at Oak Ridge National Laboratory (ORNL) under the US Department of Energy, Office of Nuclear Energy, Advanced Reactor Safeguards (ARS) program to investigate safeguards and security by design concepts, licensing and regulatory considerations, and dynamic system-level modeling to understand radioisotope concentrations for salt-fueled MSRs. The report builds upon the previous research and literature, identifies the MC&A challenges inherent to a salt-fueled MSR, reviews current regulatory frameworks for LWRs and their applicability towards salt-fueled MSRs, summarizes the status and progress of an MSR dynamic modeling tool, and discusses a prospective MC&A approach based on the Molten Salt Demonstration Reactor (MSDR) model.
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗