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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 541 records · Page 30
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Space construction base support requirements for environmental control and life support systems

A Space Station analysis study is being performed for NASA which identifies cost-effective Space Station options that can provide a space facility capable of performing space construction, space manufacturing, cosmological research, earth services, and other functions. A space construction base concept for the construction of large structures, such as those needed to implement satellite solar power for earth usage, will be used as a basis for discussing requirements that impact the design selection, level of integration, and operation of environmental control and life support systems (ECLSS). The space construction base configuration also provides a basic Space Station facility that can accommodate biological manufacturing modules, ultrapure glasses manufacturing modules, and modules for other services in a building-block fashion. Examples of special problems that could dictate hardware required to augment the basic ECLSS for autonomous modules will be highlighted. Additionally, overall intravehicular (IVA) and extravehicular (EVA) activities and requirements that could impact the basic station ECLSS degree of closure are discussed.

Thiele, R. J.↗
NASA NTRS1985

Development of countermeasures for use in space missions

Several measures used to mitigate the inappropriate adaptive responses of space flight are investigated. Weighlessness results in a cephalic fluid shift, which causes a reduction in the circulating blood volume, and removal of weight bearing forces from musculoskeletal systems. The physiological changes that occur from one-g initiated hypovolemia and zero-g initiated fluild shifts are analyzed and compared. The role of barorecptors on the activation of the adrenergic responses that occurs as a result of hypovolemia is studied. The proper selection and administration of in-flight and post flight countermeasures, which include passive and active physical conditioning techniques, drugs, and vitamins are examined.

Nicogossian, A. E. T.↗
NASA NTRS1989

STS crew escape for steady state gliding flight

The Space Transportation System goal of return to safe flight required that the Orbiter vehicle provide the crewmembers with a means of escape during controlled gliding flight. Because of its simplicity and safety the pole escape concept was selected for use during crew escape. To show that this concept would work in the Orbiter, wind tunnel tests, flight testing, and analytical simulation of the pole concept were pursued. This paper addresses each of these activities, showing how the wind tunnel test demonstrated the feasibility of the concept, how the flight testing was used to extract crew aero and Orbiter clearance margins, and how analytical simulations were used to verify Orbiter clearance margins. The analytical assessment of the Orbiter clearance margins shows that the pole concept will provide a minimum of 7-ft dispersed clearance for the NASA astronaut corps.

Millard, S. W.↗
NASA NTRS1990

Faults and ridges - Historical development in Tempe Terra and Ulysses Patera regions of Mars

Tempe Terra and the area north of Ulysses Patera are selected to demonstrate the various stages of faulting and ridge development in local areas. This work is accomplished by using Viking photomosaics to determine crosscutting relations of structures as well as their morphology and trend orientations. Results show that from the Early Noachian through the Early Amazonian Epochs, at least eight episodes of faulting occurred at Tempe Terra and six at Ulysses Patera. Tectonic activity at Tempe Terra was expressed mainly by densely spaced faults along the northeast extension of the Tharsis rise; faulting culminated in the Middle and Late Noachian and was superseded by transverse fault systems from the Alba Patera region during the Hesperian. Ridge formation, however, was most active in the Early Hesperian. At Ulysses Patera, an early history of tectonism is recorded by complex arrays of faults in a relatively small area of Noachian rocks.

Scott, D. H.↗
NASA NTRS1992

Research and technology, 1991. Langley Research Center

The mission of the NASA Langley Research Center is to increase the knowledge and capability of the United States in a full range of aeronautics disciplines and in selected space disciplines. This mission will be accomplished by performing innovative research relevant to national needs and Agency goals, transferring technology to users in a timely manner, and providing development support to other United States Government agencies, industry, and other NASA centers. Highlights are given of the major accomplishments and applications that have been made during the past year. The highlights illustrate both the broad range of the research and technology (R&T) activities at NASA Langley Research Center and the contributions of this work toward maintaining United States leadership in aeronautics and space research.

Source record↗
NASA NTRS2000

Development of the Materials Science Research Facility (MSRF) and Experiment Apparatus for the International Space Station (ISS)

The Materials Science Research Facility (MSRF) is a modular facility designed to accommodate the current and evolving cadre of peer-reviewed materials science investigations selected to conduct research in the microgravity environment of the International Space Station (ISS). The MSRF concept consists of three Materials Science Research Racks (MSRR-1, MSRR-2, and MSRR-3) which will be developed for phased deployment into the United States Laboratory Module beginning on the third Utilization Flight (UF-3). The facility will house the materials processing apparatus and common subsystems required for operating each device, and will use the ISS Active Rack Isolation System (ARIS). Each MSRR is an autonomous rack and will be comprised of on-orbit replaceable Experiment Modules, Module Inserts, investigation unique apparatus, and/or multi-user generic processing apparatus. The MSRF will be the primary apparatus for satisfying near-term and long-range materials science discipline goals and objectives with each MSRR supporting a wide range of materials science themes in the NASA research program.

Schaefer, D. A.↗
NASA NTRS2008

Estimated Environmental Exposures for MISSE-3 and MISSE-4

Both modeling techniques and a variety of measurements and observations were used to characterize the environmental conditions experienced by the specimens flown on the MISSE-3 (Materials International Space Station Experiment) and MISSE-4 space flight experiments. On August 3, 2006, astronauts Jeff Williams and Thomas Reiter attached MISSE-3 and -4 to the Quest airlock on ISS, where these experiments were exposed to atomic oxygen (AO), ultraviolet (UV) radiation, particulate radiation, thermal cycling, meteoroid/space debris impact, and the induced environment of an active space station. They had been flown to ISS during the July 2006 STS-121 mission. The two suitcases were oriented so that one side faced the ram direction and one side remained shielded from the atomic oxygen. On August 18,2007, astronauts Clay Anderson and Dave Williams retrieved MISSE-3 and-4 and returned them to Earth at the end of the STS-118 mission. Quantitative values are provided when possible for selected environmental factors. A meteoroid/debris impact survey was performed prior to de-integration at Langley Research Center. AO fluences were calculated based on mass loss and thickness loss of thin polymeric films of known AO reactivity. Radiation was measured with thermoluminescent detectors. Visual inspections under ambient and "black-light" at NASA LaRC, together with optical measurements on selected specimens, were the basis for the initial contamination level assessment.

Pippin, Gary↗
NASA NTRSDate not supplied

A Simulated High CO 2 Spaceflight Environment Increases Plant Preference for Ammonium as a Nitrogen Source.

Future long-duration missions will require a sustainable supply of food to support human crews. The spaceflight cabin environment often contains very high concentrations of CO 2 due to release of CO 2 by astronauts that is not completely scrubbed from the cabin, and it is therefore crucial to understand plant responses to elevated CO 2 (eCO 2 ) environments. Much focus has been given to changes in plant photosynthetic and performance parameters in response to eCO 2 , but the effects of eCO 2 on nitrogen (N) uptake are poorly understood. Shoot nitrate reduction may be reduced at eCO 2 , likely due to less reductant available for nitrate reduction because of reduced photorespiration and increased carbon fixation 1. Relative growth rate can be reduced at eCO 2 when N is provided only as nitrate and can be unaffected when N is supplied as ammonium 1. However, N uptake in response to eCO 2 has, to our knowledge, not yet been studied. An increased ‘preference’ for plants to take up N as ammonium at eCO 2 could have important implications for growth in the space environment, where N is currently only supplied as nitrate. In this study, novel stable isotope approaches were used in conjunction with hydroponics and isotope ratio mass spectrometry to determine the effect of eCO 2 on N preference for ammonium or nitrate in spring barley and lettuce when both N forms are provided equally. Several varieties of spring barley displayed increased ammonium preference at eCO 2 (720 ppm) compared to ambient CO 2 (410 ppm), though this was not true for all varieties 2. In most cases, increases in ammonium preference were driven by increases in ammonium uptake at eCO 2 and not decreases in nitrate uptake. Current research is assessing whether similar responses are observed in the candidate space crop lettuce, at levels of CO 2 like those observed on ISS (3000 ppm), and these results will also be presented. This work will enable the development of optimized nutrient regimes for candidate crops in space environments and the selection of crop varieties adapted to eCO 2 environments. Plants adapted to ammonium nutrition may play a role in future plant-based bioregenerative life support systems with higher ammonium concentrations due to waste recycling 3. Moreover, this research will further our understanding of plant responses to the eCO 2 environment brought about by climate change, allowing the development of future-proof crops that will help to maintain food security. References: 1. Bloom (2015). The increasing importance of distinguishing among plant nitrogen sources. Current Opinion in Plant Biology 25, 10-16. 2. Fountain (2023). Understanding interactions of barley (Hordeum vulgare) with soil nitrogen cycling activity and links to plant nitrogen preference. Ph.D. Thesis, The University of Sheffield. 3. Schiefloe et al. (2023). From urine to food and oxygen: effects of high and low NH4+:NO3- ratio on lettuce cultivated in a gas-tight hydroponic facility. Frontiers in Plant Science 14:1229476.

nitrogen↗
NASA NTRS1985

Suprathermal O(+) and H(+) ion behavior during the March 22, 1979 (CDAW 6), substorms

The present investigation has the objective to report on the behavior of energetic (approximately 130 keV) O(+) ions in the earth's plasma sheet, taking into account observations by the ISEE 1 spacecraft during a magnetically active time interval encompassing two major substorms on March 22, 1979. Attention is also given to suprathermal H(+) and He(++) ions. ISEE 1 plasma sheet observations of the proton and alpha particle phase space densities as a function of energy per charge during the time interval 0933-1000 UT on March 22, 1979 are considered along with the proton phase space density versus energy in the energy interval approximately 10 to 70 keV for the selected time periods 0933-1000 UT (presubstorm) and 1230-1243 UT (recovery phase) during the 1055 substorm on March 22, 1979. A table listing the proton energy density for presubstorm and recovery periods is also provided.

Ipavich, F. M.↗
NASA NTRS1987

Long term cryogenic storage facility systems study

The Long Term Cryogenic Storage Facility Systems Study (LTCSFSS) is a Phase A study of a large capacity propellant depot for the space based, cryogenic orbital transfer vehicle. The study is being performed for Marshall Space Flight Center by General Dynamics Space Systems Division and has five principal objectives: (1) Definition of preliminary concept designs for four storage facility concepts; (2) Selection of preferred concepts through the application of trade studies to candidate propellant management system components; (3) Preparation of a conceptual design for an orbital storage facility; (4) Development of supporting research and technology requirements; and (5) Development of a test program to demonstrate facility performance. The initial study has been completed, and continuation activities are just getting under way to provide greater detail in key areas and accommodate changes in study guidelines and assumptions.

Schuster, John R.↗
NASA NTRS1994

Hydrazine-Vapor Samplers

Active sampling unit capable of detecting hydrazine and monomethyl hydrazine vapors at levels as low as 10 ppb in air developed. Includes detachable badge holder and pump which draws air through badge holder at selectable rate of 1 or 2 L/min. Coated strip in each badge designed to align with air passage in badge holder. Two types of badge holders constructed: one has open-face design for general monitoring of air in open spaces, while other has closed-face design with viewing window and intended for sampling through small openings to detect leaks.

Young, Rebecca↗
NASA NTRS1993

A prototype to automate the video subsystem routing for the video distribution subsystem of Space Station Freedom

The Video Distribution Subsystem (VDS) for Space Station Freedom provides onboard video communications. The VDS includes three major functions: external video switching; internal video switching; and sync and control generation. The Video Subsystem Routing (VSR) is a part of the VDS Manager Computer Software Configuration Item (VSM/CSCI). The VSM/CSCI is the software which controls and monitors the VDS equipment. VSR activates, terminates, and modifies video services in response to Tier-1 commands to connect video sources to video destinations. VSR selects connection paths based on availability of resources and updates the video routing lookup tables. This project involves investigating the current methodology to automate the Video Subsystem Routing and developing and testing a prototype as 'proof of concept' for designers.

Betz, Jessie M. Bethly↗
NASA NTRS1995

Ground-based grasslands data to support remote sensing and ecosystem modeling of terrestrial primary production

Estimating terrestrial net primary production (NPP) using remote-sensing tools and ecosystem models requires adequate ground-based measurements for calibration, parameterization, and validation. These data needs were strongly endorsed at a recent meeting of ecosystem modelers organized by the International Geosphere-Biosphere Program's (IGBP's) Data and Information System (DIS) and its Global Analysis, Interpretation, and Modelling (GAIM) Task Force. To meet these needs, a multinational, multiagency project is being coordinated by the IGBP DIS to compile existing NPP data from field sites and to regionalize NPP point estimates to various-sized grid cells. Progress at Oak Ridge National Laboratory (ORNL) on compiling NPP data for grasslands as part of the IGBP DIS data initiative is described. Site data and associated documentation from diverse field studies are being acquired for selected grasslands and are being reviewed for completeness, consistency, and adequacy of documentation, including a description of sampling methods. Data are being compiled in a database with spatial, temporal, and thematic characteristics relevant to remote sensing and global modeling. NPP data are available from the ORNL Distributed Active Archive Center (DAAC) for biogeochemical dynamics. The ORNL DAAC is part of the Earth Observing System Data and Information System, of the US National Aeronautics and Space Administration.

Olson, R. J.↗
NASA NTRSDate not supplied

Digital Lunar Exploration Sites (DLES)

It has been almost 50 years since humans last set foot on the Moon. With NASA’s Artemis program, the United States and its international and commercial partners are embarking on a new endeavor to explore the lunar surface. Before we return, we will have simulated every aspect of these future missions. Many of these models and simulations (M&S) will rely on well-known and commonly-used technologies, some of which trace their origins back to the Apollo program. However, M&S has advanced significantly, as have the underlying computational capabilities. As a result, we are able to model many more aspects of the Artemis vehicles and support systems with significantly improved detail and confidence. Accurately and efficiently modeling the lunar environment will be critical to simulating the Artemis elements and mission activities. This includes characterizing and modeling lunar topography, smaller craters, exposed surface rocks, lunar regolith, surface lighting, and ambient thermal environment. These are all necessary for understanding fundamental behaviors and performance of vehicles and support systems in the lunar environment and are often determining factors in the selection of exploration sites and defining mission profiles. The Astromaterials Research and Exploration Sciences (ARES) team in the Exploration Integration and Science Directorate at NASA’s Johnson Space Center (JSC) and the NASA Exploration Systems Simulations (NExSyS) team in the Simulation and Graphics Branch at JSC are developing and maintaining the Digital Lunar Exploration Sites (DLES) data, documentation, and software packages. This data is being fed directly into a diverse collection of graphics and simulation environments, where it is used to construct the closest known truth for numerous potential Lunar South Pole landing sites. DLES is available to projects across NASA and particularly the Artemis program to support coordinated digital representations of the lunar environment. This paper describes the fundamental need for DLES, the science data sets that are going into DLES, some of the processes used to integrate this data into DLES products, the basic products that constitute DLES, and some examples of DLES in use.

Lunar↗
NASA NTRS1979

An active thermal control surfaces experiment

An active flight experiment is described that has the objectives to determine the effects of the low earth natural environment and the Shuttle induced environment on selected thermal control and optical surfaces. The optical and thermal properties of test samples will be measured in-situ using an integrating sphere reflectrometer and using calorimetric methods. This experiment has been selected for the Long Duration Exposure Facility (LDEF) flight which will be carried to orbit by the NASA Space Shuttle. The LDEF will remain in orbit to be picked up by a later Shuttle mission and returned for postflight evaluation.

Wilkes, D. R.↗
NASA NTRS1987

Long term orbital storage of cryogenic propellants for advanced space transportation missions

A comprehensive study has developed the major features of a large capacity orbital propellant depot for the space-based, cryogenic OTV. The study has treated both the Dual-Keel Space Station and co-orbiting platforms as the accommodations base for the propellant storage facilities, and trades have examined both tethered and hard-docked options. Five tank set concepts were developed for storing the propellants, and along with layout options for the station and platform, were evaluated from the standpoints of servicing, propellant delivery, boiloff, micrometeoroid/debris shielding, development requirements, and cost. These trades led to the recommendation that an all-passive storage concept be considered for the platform and an actively refrigerated concept providing for reliquefaction of all boiloff be considered for the Space Station. The tank sets are modular, each storing up to 45,400 kg of LO2/LH2, and employ many advanced features to provide for microgravity fluid management and to limit boiloff. The features include such technologies as zero-gravity mass gauging, total communication capillary liquid acquisition devices, autogenous pressurization, thermodynamic vent systems, thick multilayer insulation, vapor-cooled shields, solar-selective coatings, advanced micrometeoroid/debris protection systems, and long-lived cryogenic refrigeration systems.

Schuster, John R.↗
NASA NTRS1991

Closed-form solutions for linear regulator-design of mechanical systems including optimal weighting matrix selection

This paper addresses the restriction of Linear Quadratic Regulator (LQR) solutions to the algebraic Riccati Equation to design spaces which can be implemented as passive structural members and/or dampers. A general closed-form solution to the optimal free-decay control problem is presented which is tailored for structural-mechanical systems. The solution includes, as subsets, special cases such as the Rayleigh Dissipation Function and total energy. Weighting matrix selection is a constrained choice among several parameters to obtain desired physical relationships. The closed-form solution is also applicable to active control design for systems where perfect, collocated actuator-sensor pairs exist. Some examples of simple spring mass systems are shown to illustrate key points.

Hanks, Brantley R.↗
NASA NTRS1991

Optical phase measuring sensors for automated rendezvous and capture

A technique is described for sensing relative spatial orientations of approach and target vehicles, using optical phase mensuration (in the interferometric sense, as opposed to LIDAR), in place of the more conventional intensity, image, or transit time measurements. This approach permits the parameters to be measured with great accuracy with relatively simple, small sensors having no moving components. A suite of sensors operating on this principle can produce all desired data using either active detection on the target or passive retroreflection to the detectors on the approach vehicle. These optical phase measurements can be applied to determine bearing angle (location of the target vehicle in the approach vehicle coordinates), range, and attitude (orientation of the target vehicle with respect to the line-of-sight). The first two quantities require the approach vehicle to project a modulated interference pattern into space. The bearing angle is determined for a selected point on the target by measuring the phase of the interference pattern at that point using either a detector on the target or a retroreflector on the target and a detector at the transmitter. The range is found by measuring differential bearing angles to predetermined relative instrumentation sites. Two interferometers, a coarse and a fine ranger are required to resolve the 2pi ambiguity.

Metheny, Wayne↗