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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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NASA NTRS1990

A homogeneous sample of binary galaxies: Basic observational properties

A survey of optical characteristics for 585 binary systems, satisfying a condition of apparent isolation on the sky, is presented. Influences of various selection effects distorting the average parameters of the sample are noted. The pair components display mutual similarity over all the global properties: luminosity, diameter, morphological type, mass-to-luminosity ratio, angular momentum etc., which is not due only to selection effects. The observed correlations must be caused by common origin of pair members. Some features (nuclear activity, color index) could acquire similarity during synchronous evolution of double galaxies. Despite the observed isolation, the sample of double systems is seriously contaminated by accidental pairs, and also by members of groups and clusters. After removing false pairs estimates of orbital mass-to-luminosity ratio range from 0 to 30 f(solar), with the mean value (7.8 plus or minus 0.7) f(solar). Binary galaxies possess nearly circular orbits with a typical eccentrity e = 0.25, probably resulting from evolutionary selection driven by component mergers under dynamical friction. The double-galaxy population with space abundance 0.12 plus or minus 0.02 and characteristic merger timescale 0.2 H(exp -1) may significantly influence the rate of dynamical evolution of galaxies.

Karachentsev, I. D.↗

NASA NTRS1991

System concepts for a large UV/optical/IR telescope on the moon

To assess the systems and technological requirements for constructing lunar telescopes in conjunction with the buildup of a lunar base for scientific exploration and as a waypoint for travel to Mars, the NASA Marshall Space Flight Center conducted concept studies of a 16-m-aperture large lunar telescope (LLT) and a 4-m-aperture precursor telescope, both operating in the UV/visible/IR spectral region. The feasibility of constructing a large telescope on the lunar surface is assessed, and its systems and subsystems are analyzed. Telescope site selection, environmental effects, and launch and assembly scenarios are also evaluated. It is argued that key technical drivers for the LLT must be tested in situ by precursor telescopes to evaluate such areas as the operations and long-term reliability of active optics, radiation protection of instruments, lunar dust mitigation, and thermal shielding of the telescope systems. For a manned lunar outpost or an LLT to become a reality, a low-cost dependable transportation system must be developed.

Nein, Max E.↗

NASA NTRSDate not supplied

Evaluation of Materials and Surfaces for Lunar Regolith Adherence Characterization (RAC) Payload Samples

As the quest for long term lunar exploration and habitation comes closer to reality, widespread efforts are ongoing to effectively mitigate lunar dust surface contamination and infiltration. This dust is hazardous to humans and tends to adhere tenaciously to all exposed surfaces, causing performance issues and ultimately failure. While several active and passive technologies have been developed to address this challenge, assessing the performance of these technologies in the actual lunar environment is extremely important. The regolith adherence characterization (RAC) experiment payload provides an important opportunity for this evaluation. The RAC payload is designed by Alpha Space for the National Aeronautics and Space Administration (NASA)and scheduled to be flown to the moon in 2023 on the Firefly Aerospace Blue Ghost lander. As there were a limited number of slots available for materials to be chosen for this mission, it was critical to make an informed selection. Two polymers, a carbon fiber reinforced composite and a metal alloy were chosen to be a diverse selection of structural materials from NASA Langley Research Center. Each material was topographically modified using laser ablation patterning. This article briefly describes the selection and testing procedure and some of the results obtained for the passive dust mitigating materials and surfaces selected for this lunar surface experiment.

Lunar Dust↗

NASA NTRS2023

Exploration Habitat (X-Hab) 2013-2014 Academic Innovation Challenge

Outreach activities were coordinated with OSU’s NASA Education Office and focused around the Space Habitat Innovation Challenge. Two challenges were developed for this year: the Rapidly Prototyped Tool Challenge (RaPTC) and the Space Habitat Airlock Challenge (SHAC). RaPTC was open to eligible high school student teams while SHAC was open to eligible community college student teams. Teams involved 3-6 students from 12 states across the country and submitted videos or virtual presentations.1 Entries were judged by the OSU XHab students and were provided with feedback on feasibility and design. Three groups in each challenge were selected as finalists for a final virtual presentation and interview with students and professors in the engineering program at Oklahoma State University. Three groups total were selected to present their design to engineers and astronauts at a NASA JSC. Judges included astronauts Joe Acaba, Nicole Stott, and Dottie Metcalf-Lindenburger.

Jamey D Jacob↗

NASA NTRSDate not supplied

Development of the Miniature Total Organic Carbon Analyzer

Monitoring the Total Organic Carbon (TOC) in spacecraft potable water will be of major importance in long-duration human space exploration. In-flight analysis of potable water produced from a regenerative water processor provides immediate feedback on the quality of reclaimed water for crew health as well as water processing system health monitoring. This paper updates the progress in development of the next generation Total Organic Carbon Analyzer (TOCA) designed for the unique requirements of an exploration-class mission. The current objective is to design, build, certify, deliver, and operate a TOCA technology demonstration on the International Space Station (ISS). The next generation analyzer system technology was previously developed and selected among a feasibility study of other options. The new system provides primary advantages of reduced mass and volume through reduced system complexity and reduced need for consumables; therefore, the flight project is named MiniTOCA. The project has recently completed design of the tech demo instrument and assembled and tested a flight-like engineering development unit. The engineering unit has undergone performance testing and environmental testing which provides confidence for the project to move forward with flight unit production and certification activities. Test results are summarized in this paper. The flight unit is targeted for delivery to ISS in late 2025.

TOC↗

NASA NTRSDate not supplied

Development of the Miniature Total Organic Carbon Analyzer

TOC↗

NASA NTRS2000

A natural basis for efficient brain-actuated control

The prospect of noninvasive brain-actuated control of computerized screen displays or locomotive devices is of interest to many and of crucial importance to a few 'locked-in' subjects who experience near total motor paralysis while retaining sensory and mental faculties. Currently several groups are attempting to achieve brain-actuated control of screen displays using operant conditioning of particular features of the spontaneous scalp electroencephalogram (EEG) including central mu-rhythms (9-12 Hz). A new EEG decomposition technique, independent component analysis (ICA), appears to be a foundation for new research in the design of systems for detection and operant control of endogenous EEG rhythms to achieve flexible EEG-based communication. ICA separates multichannel EEG data into spatially static and temporally independent components including separate components accounting for posterior alpha rhythms and central mu activities. We demonstrate using data from a visual selective attention task that ICA-derived mu-components can show much stronger spectral reactivity to motor events than activity measures for single scalp channels. ICA decompositions of spontaneous EEG would thus appear to form a natural basis for operant conditioning to achieve efficient and multidimensional brain-actuated control in motor-limited and locked-in subjects.

NASA Discipline Space Human Factors↗

NASA NTRS1974

A movable-mass attitude stabilization system for cable-connected artificial-g space stations

The development of an active, momentum-exchange system to be used for attitude stabilization of a class of cable-connected artificial-g space stations is studied. A system which employs a single movable control mass is examined for the control of a space station which has the physical appearance of two cylinders connected axially by cables. The dynamic model for the space station includes its aggregate rigid body rotation and relative torsional rotation between the bodies. A zero torsional stiffness design (one cable) and a maximum torsional stiffness design (eight cables) are examined in various stages of deployment, for selected spin velocities ranging from 4 rpm upwards. A linear, time-invariant, feed-back control system is employed, with gains calculated via a root-specification procedure. The movable mass controller provides critical wobble-damping capability for the crew quarters for all configurations and spin velocity.

Childs, D. W.↗

NASA NTRS1986

Integrated analysis tools for trade studies of spacecraft controller and sensor locations

The present investigation was conducted with the aim to evaluate the practicality and difficulties of modern control design methods for large space structure controls. The evaluation is used as a basis for the identification of useful computer-based analysis tools which would provide insight into control characteristics of a spacecraft concept. A description is presented of the wrap-rib antenna and its packaging concept. Attention is given to active control requirements, a mathematical model of structural dynamics, aspects of sensor and actuator location, the analysis approach, controllability, observability, the concept of balanced realization, transmission zeros, singular value plots, analysis results, model reduction, and an interactive computer program. It is pointed out that the application of selected control analysis tools to the wrap-rib antenna demonstrates several capabilities which can be useful during conceptual design.

Rowell, L. F.↗

NASA NTRS1995

Teacher Enhancement and Preparation Programs

These two programs provide opportunities for K-12 teachers of mathematics, science, and technology to spend two weeks at a NASA center learning about aeronautics and space. Participants are selected by peer review from a contracting agent that assists NASA in administering the program. Each teacher receives a stipend that covers the cost of travel, housing, meals, and graduate credit. NEWMAST provides for approximately 100 secondary teachers, and NEWTEST is a program designed to meet the needs of approximately 125 elementary teachers each summer. Teachers are provided with a wide variety of experiences including research laboratory observations, presentations, and 'shadowships'. Individual and team projects are used to enhance the participants knowledge of space and aeronautics and to motivate the teachers to incorporate the summer workshop activities into their classrooms.

Source record↗

NASA NTRS2000

Critical Path Web Site

Approximately three years ago, the Agency's lead center for the human elements of spaceflight (the Johnson Space Center), along with the National Biomedical Research Institute (NSBRI) (which has the lead role in developing countermeasures) initiated an activity to identify the most critical risks confronting extended human spaceflight. Two salient factors influenced this activity: first, what information is needed to enable a "go/no go" decision to embark on extended human spaceflight missions; and second, what knowledge and capabilities are needed to address known and potential health, safety and performance risks associated with such missions. A unique approach was used to first define and assess those risks, and then to prioritize them. This activity was called the Critical Path Roadmap (CPR) and it represents an opportunity to develop and implement a focused and evolving program of research and technology designed from a "risk reduction" perspective to prevent or minimize the risks to humans exposed to the space environment. The Critical Path Roadmap provides the foundation needed to ensure that human spaceflight, now and in the future, is as safe, productive and healthy as possible (within the constraints imposed on any particular mission) regardless of mission duration or destination. As a tool, the Critical Path Roadmap enables the decisionmaker to select from among the demonstrated or potential risks those that are to be mitigated, and the completeness of that mitigation. The primary audience for the CPR Web Site is the members of the scientific community who are interested in the research and technology efforts required for ensuring safe and productive human spaceflight. They may already be informed about the various space life sciences research programs or they may be newcomers. Providing the CPR content to potential investigators increases the probability of their delivering effective risk mitigations. Others who will use the CPR Web Site and its content include program managers and administrators who track the program and are involved in decisions regarding resource allocation and program evaluation.

Robinson, Judith L.↗

NASA NTRS2001

Use of the Aerosonde Unihabited Aerial Vehicle (UAV) in the Fourth Convection and Moisture Experiment (CAMEX 4)

The Fourth Convection and Moisture Experiment (CAMEX 4) was a scientific field experiment based in Florida in summer 2001 focused on the study of hurricanes off the east coast of the United States. Sponsored by the National Aeronautics and Space Administration's Office of Earth Science, and conducted in collaboration with the National Oceanic and Atmospheric Administration's annual hurricane research program, CAMEX 4 utilized aircraft, ground-based and satellite instrumentation to obtain unprecedented, three dimensional characterizations of these important storms. The Aerosonde UAV was selected by NASA to participate in CAMEX 4 because it provided a unique capability to obtain measurements in the atmospheric boundary layer in and around the storms, unattainable by other platforms or measurement capabilities. This talk focuses on the NASA review process that was followed to coordinate the UAV activity with the conventional aircraft operations, as well as with the other participating agencies and the FAA. We will discuss how Aerosonde addressed the issues of safety, coordination and communication and summarize the lessons learned.

Hipskind, R. Stephen↗

NASA NTRS2012

Expedition Earth and Beyond: Using Crew Earth Observation Imagery from the International Space Station to Facilitate Student-Led Authentic Research

Student-led authentic research in the classroom helps motivate students in science, technology, engineering, and mathematics (STEM) related subjects. Classrooms benefit from activities that provide rigor, relevance, and a connection to the real world. Those real world connections are enhanced when they involve meaningful connections with NASA resources and scientists. Using the unique platform of the International Space Station (ISS) and Crew Earth Observation (CEO) imagery, the Expedition Earth and Beyond (EEAB) program provides an exciting way to enable classrooms in grades 5-12 to be active participants in NASA exploration, discovery, and the process of science. EEAB was created by the Astromaterials Research and Exploration Science (ARES) Education Program, at the NASA Johnson Space Center. This Earth and planetary science education program has created a framework enabling students to conduct authentic research about Earth and/or planetary comparisons using the captivating CEO images being taken by astronauts onboard the ISS. The CEO payload has been a science payload onboard the ISS since November 2000. ISS crews are trained in scientific observation of geological, oceanographic, environmental, and meteorological phenomena. Scientists on the ground select and periodically update a series of areas to be photographed as part of the CEO science payload.

Graff, P. V.↗

NASA NTRSDate not supplied

Combinatorial Auction-Based Strategic Deconfliction of Federated UTM Airspace

Unmanned Aerial Vehicles (UAVs) have become commonly used to perform a wide range of commercial activities such as cinematography and medical supply delivery. Consequently, regulators have become interested in designing UAV Traffic Management systems (UTMs) to coordinate UAV traffic among a collection of UAV operators. One framework which has been recently proposed for a UTM system is a combinatorial auction. In this framework, airspace is modelled as a 4D grid of space-time cells. UAV operators bid on cells which collectively form paths for their UAVs. Ideally, an airspace auction should reveal information about the current price of flight paths to bidders, allowing bidders to identify and bid on a select number of paths instead of placing as many bids as possible in the hopes of stumbling on a cheap path. Revealing too much information, however, can allow bad actors to place bids which are intended not to win but to raise the price that a rival bidder must pay. We address these twin challenges with a new information revelation framework which provides bidders with wide-ranging pricing information while suppressing bad actors. We evaluate our framework on scenarios based on a Japan Aerospace Exploration Agency (JAXA) case study and find that it can scale to thousands of bids.

Christopher J C Leet↗

NASA NTRS1981

Combustion experimentation aboard the space transportation system

A description is presented of the preliminary concept, specifications, and general requirements of a proposed Combustion Facility (CF) for the Spacelab payload of the Space Transportation System. The CF will permit an experimenter to use suitably contained liquid, gas, or solid fuels. He can specify and establish the composition and pressure level of the atmosphere in which the combustion will take place. It will be possible to characterize the experiment with common types of instrumentation as well as selected specialized equipment, to study the combustion process visually by direct observation and by motion picture coverage, and to obtain time histories of pertinent experimental parameters. During an experimental period, the CF will depend on Spacelab resources for power, heat rejection, and vacuum. Activating the CF and preparing it for the various experiments, performing the experiments, and shutting down the facility will be largely manual operations performed by flight personnel.

Dewitt, R. L.↗

NASA NTRS1986

Second generation spectrograph for the Hubble Space Telescope

The preliminary design for the Space Telescope Imaging Spectrograph (STIS), which has been selected by NASA for definition study for future flight as a second-generation instrument on the Hubble Space Telescope (HST), is presented. STIS is a two-dimensional spectrograph that will operate from 1050 A to 11,000 A at the limiting HST resolution of 0.05 arcsec FWHM, with spectral resolutions of 100, 1200, 20,000, and 100,000 and a maximum field-of-view of 50 x 50 arcsec. Its basic operating modes include echelle model, long slit mode, slitless spectrograph mode, coronographic spectroscopy, photon time-tagging, and direct imaging. Research objectives are active galactic nuclei, the intergalactic medium, global properties of galaxies, the origin of stellar systems, stelalr spectral variability, and spectrographic mapping of solar system processes.

Woodgate, B. E.↗

NASA NTRS1987

Investigation into the development of computer aided design software for space based sensors

The described effort is phase one of the development of a Computer Aided Design (CAD) software to be used to perform radiometric sensor design. The software package will be referred to as SCAD and is directed toward the preliminary phase of the design of space based sensor system. The approach being followed is to develop a modern, graphic intensive, user friendly software package using existing software as building blocks. The emphasis will be directed toward the development of a shell containing menus, smart defaults, and interfaces, which can accommodate a wide variety of existing application software packages. The shell will offer expected utilities such as graphics, tailored menus, and a variety of drivers for I/O devices. Following the development of the shell, the development of SCAD is planned as chiefly selection and integration of appropriate building blocks. The phase one development activities have included: the selection of hardware which will be used with SCAD; the determination of the scope of SCAD; the preliminary evaluation of a number of software packages for applicability to SCAD; determination of a method for achieving required capabilities where voids exist; and then establishing a strategy for binding the software modules into an easy to use tool kit.

Pender, C. W.↗

NASA NTRS2000

Critical Path Web Site

Approximately three years ago, the Agency's lead center for the human elements of spaceflight (the Johnson Space Center), along with the National Biomedical Research Institute (NSBRI) (which has the lead role in developing countermeasures) initiated an activity to identify the most critical risks confronting extended human spaceflight. Two salient factors influenced this activity: first, what information is needed to enable a "go/no go" decision to embark on extended human spaceflight missions; and second, what knowledge and capabilities are needed to address known and potential health, safety and performance risks associated with such missions. A unique approach was used to first define and assess those risks, and then to prioritize them. This activity was called the Critical Path Roadmap (CPR) and it represents an opportunity to develop and implement a focused and evolving program of research and technology designed from a "risk reduction" perspective to prevent or minimize the risks to humans exposed to the space environment. The Critical Path Roadmap provides the foundation needed to ensure that human spaceflight, now and in the future, is as safe, productive and healthy as possible (within the constraints imposed on any particular mission) regardless of mission duration or destination. As a tool, the Critical Path Roadmap enables the decision maker to select from among the demonstrated or potential risks those that are to be mitigated, and the completeness of that mitigation. The primary audience for the CPR Web Site is the members of the scientific community who are interested in the research and technology efforts required for ensuring safe and productive human spaceflight. They may already be informed about the various space life sciences research programs or they may be newcomers. Providing the CPR content to potential investigators increases the probability of their delivering effective risk mitigations. Others who will use the CPR Web Site and its content include program managers and administrators who track the program and are involved in decisions regarding resource allocation and program evaluation.

Robinson, Judith L.↗