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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 NTRS2000

Power and On-Board Propulsion System Benefit Studies at NASA GRC

This paper discusses the value of systems studies that provide unbiased 'honest broker' assessments of the quantified benefits afforded by advanced technologies for specific missions. The organization, format, and approach used by the NASA Glenn Research Center (GRC) Systems Assessment Team (SAT) to perform system studies for the GRC advanced power and on-board propulsion technology development program is described. Three levels of assessments and a sensitivity analysis are explained and example results are presented. The impact of system studies results and some of the main challenges associated with systems studies are identified. A call for collaboration is made where system studies of all types from all organizations can be reviewed, providing a forum for the widest peer review to ensure accurate and unbiased technical content, and to avoid needless duplication.

Hoffman, David J.↗
NASA NTRS2000

Support to X-33/Resusable Launch Vehicle Technology Program

The X-33 Guidance, Navigation, and Control (GN&C) Peer Review Team (PRT) was formed to assess the integrated X-33 vehicle GN&C system in order to identify any areas of disproportionate risk for initial flight. The eventual scope of the PRT assessment encompasses the GN&C algorithms, software, avionics, control effectors, applicable models, and testing. The initial (phase 1) focus of the PRT was on the GN&C algorithms and the Flight Control Actuation Subsystem (FCAS). The PRT held meetings during its phase 1 assessment at X-33 assembly facilities in Palmdale, California on May 17-18, 2000 and at Honeywell facilities in Tempe, Arizona on June 7, 2000. The purpose of these meetings was for the PRT members to get background briefings on the X-33 vehicle and for the PRT team to be briefed on the design basis and current status of the X-33 GN&C algorithms as well as the FCAS. The following material is covered in this PRT phase 1 final report. Some significant GN&C-related accomplishments by the X-33 development team are noted. Some topics are identified that were found during phase 1 to require fuller consideration when the PRT reconvenes in the future. Some new recommendations by the PRT to the X-33 program will likely result from a thorough assessment of these subjects. An initial list of recommendations from the PRT to the X-33 program is provided. These recommendations stem from topics that received adequate review by the PRT in phase 1. Significant technical observations by the PRT members as a result of the phase 1 meetings are detailed. (These are covered in an appendix.) There were many X-33 development team members who contributed to the technical information used by the PRT during the phase 1 assessment, who supported presentations to the PRT, and who helped to address the many questions posed by the PRT members at and after the phase 1 meetings. In all instances the interaction between the PRT and the X-33 development team members was cordial and very professional. The members of the PRT are grateful for the time and effort applied by all of these individuals and hope that the contents of this report will help to make the X-33 program a success.

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NASA NTRS2000

Theoretical Modeling and Computer Simulations for the Origins and Evolution of Reproducing Molecular Systems and Complex Systems with Many Interactive Parts

Our research effort has produced nine publications in peer-reviewed journals listed at the end of this report. The work reported here are in the following areas: (1) genetic network modeling; (2) autocatalytic model of pre-biotic evolution; (3) theoretical and computational studies of strongly correlated electron systems; (4) reducing thermal oscillations in atomic force microscope; (5) transcription termination mechanism in prokaryotic cells; and (6) the low glutamine usage in thennophiles obtained by studying completely sequenced genomes. We discuss the main accomplishments of these publications.

Liang, Shoudan↗
NASA NTRS2001

Long-Term Space Astrophysics Program

This is the final report for our Long-Term Space Astrophysics Program (NRA 94-OSS-12) grant NAG 5-3225. The proposal is entitled 'Spectral and Temporal Properties of Black Hole Candidates', and began funding in May 1995, and ran through 31 Aug 2000. The project summary from the original proposal was as follows: 'We will study the spectral and temporal properties of black hole candidates (BHC) by using data from archival sources (e.g., EXOSAT, Ginga, ROSAT) and proposed follow-up observations with modern instruments (e.g., ASCA, XTE). Our spectral studies will focus on identifying the basic characteristics and luminosities of the emission components in the various 'states' of BHC. We hope to understand and quantify the global energetics of these states. Our temporal studies will focus on expanding and classifying our knowledge of BHC variability properties in each state. We will explore the nature of quasi-periodic oscillations in BHC. We will combine our spectral and temporal studies by analyzing time lags and variability coherence between energy channels. In addition, we will investigate ways of correlating observed variability behavior with specific emission components.' We have accomplished many of these goals laid out within the original proposal. As originally proposed, we have utilized both archival and proprietary satellite data. In terms of archival data, we have utilized data from the Advanced Satellite for Cosmology and Astrophysics (ASCA), ROSAT, and the Rossi X-ray Timing Explorer (RXTE). We also obtained proprietary data from ASCA, RXTE, and the Extreme Ultraviolet Explorer (EUVE). In terms of sources, we have examined a wide variety of both galactic black hole candidates and extra-galactic black holes. For the galactic black holes we have observed and analyzed both the low/hard state and the high/soft state. We have performed both spectral and timing analyses on all of these objects. In addition, we have also examined a number of neutron stars or potential neutron stars. All of our research on the above mentioned objects has resulted in one or more publications in peer-reviewed journals. Attached is a list of refereed publications of research results which have been funded by this grant over approximately the past five and a half years. In addition, we have included a list of conference proceedings and other similar reports that have been associated with this grant.

Nowark, Michael A.↗
NASA NTRS2001

Giant Star Clusters Near Galactic Core

A video sequence of still images goes deep into the Milky Way galaxy to the Arches Cluster. Hubble, penetrating through dust and clouds, peers into the core where two giant clusters shine more brightly than any other clusters in the galaxy. Footage shows the following still images: (1) wide view of Sagittarius constellation; (2) the Palomar Observatory's 2 micron all-sky survey; and (3) an image of the Arches Cluster taken with the Hubble Space Telescope NICMOS instrument. Dr. Don Figer of the Space Telescope Science Institute discusses the significance of the observations and relates his first reaction to the images.

Source record↗
NASA NTRS2001

Beginning Research with the 1.8-meter Spacewatch Telescope

The purpose of this grant was to bring the Spacewatch 1.8-m telescope to operational status for research on asteroids and comets. This objective was achieved; first light with the telescope was in May 2000 and since then several tests and demonstrations of the facility's capability to observe Earth-approaching Asteroids (EAs) have been made, including the first observations to be incorporated into a peer-reviewed publication. The Spacewatch 1.8-m telescope will be the largest in the world dedicated full time to finding and doing astrometry of asteroids and comets. It will be used to search for asteroids and comets anywhere from the space near Earth to regions beyond the orbit of Neptune, and to do astrometry and lightcurves on the fainter of such objects that are already known. Its comparatively large aperture will permit faster discovery of the very small asteroids in Earthlike orbits, such as 1998 KY(sub 26), that are coveted for their accessibility as material resources in space, as well as recovery of EAs on their return apparitions when they tend to be more distant and fainter than they were at the times of their discoveries. It will also tend to find EAs when they do not happen to be close to Earth. Discoveries made under those circumstances allow the objects to be followed for longer intervals, providing better determinations of their orbits during their discovery apparitions. In addition to its size, the 1.8-m Spacewatch telescope will have the unique capability of long strip scanning in any direction, for example along the ecliptic (the plane of the solar system), and along the line of variation of EAs with uncertain orbits that are being targeted for recovery.

Gehrels, Tom↗
NASA NTRS2000

Materials Science Research Hardware for Application on the International Space Station: an Overview of Typical Hardware Requirements and Features

NASA's Marshall Space Flight Center (MSFC) is the lead center for Materials Science Microgravity Research. The Materials Science Research Facility (MSRF) is a key development effort underway at MSFC. The MSRF will be the primary facility for microgravity materials science research on board the International Space Station (ISS) and will implement the NASA Materials Science Microgravity Research Program. It will operate in the U.S. Laboratory Module and support U. S. Microgravity Materials Science Investigations. This facility is being designed to maintain the momentum of the U.S. role in microgravity materials science and support NASA's Human Exploration and Development of Space (HEDS) Enterprise goals and objectives for Materials Science. The MSRF as currently envisioned will consist of three Materials Science Research Racks (MSRR), which will be deployed to the International Space Station (ISS) in phases, Each rack is being designed to accommodate various Experiment Modules, which comprise processing facilities for peer selected Materials Science experiments. Phased deployment will enable early opportunities for the U.S. and International Partners, and support the timely incorporation of technology updates to the Experiment Modules and sensor devices.

Schaefer, D. A.↗
NASA NTRS1995

Application of Atmospherically Corrected Reflectance Spectra From HIRIS to the Identification and Mapping of Aeolian Components in Soils

This final report encompasses all efforts funded under NASA including the HIRIS team leader activities. The results of the HIRIS team efforts as a group is summarized in the HIRIS Science Requirements Document. The rest of the research effort is codified in a number of published papers in peer-reviewed journals and proceedings of scientific meetings. This report is organized into a series of topic headings where a short summary is given and the appropriate references cited. Copies of all the relevant papers are collected in the appendix.

Goetz, Alexander F. H.↗
NASA NTRS2001

Simultaneous Spectral and Timing Observations of Accreting Neuron Stars

The goal of this proposal was to perform simultaneous x-ray spectral and millisecond timing observations of accreting neutron stars to further our understanding of their accretion dynamics and in the hope of using these systems as probes of the physics of strong gravitational fields. Observations of the neutron star binaries 4U0614+091, 4U1728-34, 4U1820-30, and Cyg X-2 were carried out with RXTE and BeppoSAX, ASCA, and Chandra (not all simultaneously). In addition, archival data were analyzed for 4U0614+091 and 4U1820-30. This investigation led to publication of three papers in peer-reviewed journals. These are listed below. In addition, the results were presented at several meetings including the two poster presentations listed below. Dr. Santina Piraino visited SAO for 4 months during 2000 to collaborate on analysis of the data from NAG5-8408 and NAG5-9104.

Kaaret, P.↗
NASA NTRS2000

Minority University Research and Education Division (MURED) Update

Program priorities include: (1) Expand and advance NASA's scientific and technological base by building on prior year's efforts in research and academic infrastructure; (2) Increase exposure to NASA's unique mission and facilities by developing closer relationships with NASA Strategic Enterprises; (3) Increase involvement in competitive peer review and merit selection processes; (4) Contribute significantly to the Agency's strategic goals and objectives; (5) Create systemic and sustainable change through partnerships and programs that enhance research and education programs; (6) Prepare faculty and students at HBCU's for NASA-related fields and increase number of students that enter and successfully complete degrees in NASA-related fields; (7) Establish measurable program goals and objectives; and (8) Improve financial management performance.

Malone, John↗
NASA NTRS2001

Bio-Optical Measurement and Modeling of the California Current and Polar Oceans

The principal goals of our research are to validate standard or experimental products through detailed bio-optical and biogeochemical measurements, and to combine ocean optical observations with advanced radiative transfer modeling to contribute to satellite vicarious radiometric calibration and advanced algorithm development. To achieve our goals requires continued efforts to execute complex field programs globally, as well as development of advanced ocean optical measurement protocols. We completed a comprehensive set of ocean optical observations in the California Current, Southern Ocean, Indian Ocean requiring a large commitment to instrument calibration, measurement protocols, data processing and data merger. We augmented separately funded projects of our own, as well as others, to acquire ill situ data sets we have collected on various global cruises supported by separate grants or contracts. In collaboration with major oceanographic ship-based observation programs funded by various agencies (CalCOFI, US JGOFS, NOAA AMLR, INDOEX and Japan/East Sea) our SIMBIOS effort has resulted in data from diverse bio-optical provinces. For these global deployments we generate a high-quality, methodologically consistent, data set encompassing a wide-range of oceanic conditions. Global data collected in recent years have been integrated with our on-going CalCOFI database and have been used to evaluate SeaWiFS algorithms and to carry out validation studies. The combined database we have assembled now comprises more than 700 stations and includes observations for the clearest oligotrophic waters, highly eutrophic blooms, red-tides and coastal case 2 conditions. The data has been used to validate water-leaving radiance estimated with SeaWiFS as well as bio-optical algorithms for chlorophyll pigments. The comprehensive data is utilized for development of experimental algorithms (e.g. high-low latitude pigment transition, phytoplankton absorption, and cDOM). During this period we completed 9 peer-reviewed publications in high quality journals, and presented aspects of our work at more than 10 scientific conferences.

Mitchell, B. Greg↗
NASA NTRS1994

The Next Generation Airborne Observatory: SOFIA

NASA, DARA, and the astronomical community have planned SOFIA (Stratospheric Observatory for Infrared Astronomy) to extend and expand the capabilities of airborne astronomy. Just as the Kuiper Airborne Observatory telescope has three times the aperture of its Learjet predecessor, SOFIA's aperture (2.5 m) will be three times that of the KAO. Thus SOFIA will surpass the angular resolution of the KAO by a factor of three and its per-pixel sensitivity by a factor approximately 10 at wavelengths beyond 10 micrometers. Following the tradition of the KAO and Learjet programs, the user community will provide most of the SOFIA focal plane instruments. Scientists will fly their new instruments as soon as they become operational, assuring immediate application of state-of-the-art technology throughout the anticipated 20 year observatory lifetime. Annual peer review of submitted proposals guarantees a vigorous observing program. Armed by 15-20 different instrument teams, reinforced by an additional approximately 50 guest investigator groups, and flying 160 8-hour sorties per year, SOFIA will be used to attack a very broad range of astronomical problems. To name just a few, observations made from SOFIA will: greatly extend our understanding of the star-formation process, including collapse, accretion, and outflow phenomena; penetrate the obscuring dust of the Milky way to reveal gas motions, the luminosity distribution, and possibly the powerful excitation mechanism at the center of our Galaxy; and probe km-scale structure of planetary atmospheres and ring systems. The Astronomy and Astrophysics Survey (Bahcall) committee ranked SOFIA as the highest priority moderate cost new mission for NASA in the 1990s. SOFIA has been thoroughly studied and is ready to start development. If funding is available in 1996 as currently planned by NASA and DARA Astrophysics Offices, SOFIA could be flying by the end of the decade.

Erickson, E. F.↗
NASA NTRS2001

Membership and Coronal Activity in the NGC 2232 and Cr 140 Open Clusters

This is the second annual performance report for our grant "Membership and Coronal Activity in the NGC 2232 and Cr 140 Open Clusters." We propose to identify X-ray sources and extract net source counts in 8 archival ROSAT HRI images in the regions of the NGC 2232 and Cr 140 open clusters. These X-ray data will be combined with ground-based photometry and spectroscopy in order to identify G, K, and early-M type cluster members. At present, no members later than approximately F5 are currently known for either cluster. With ages of approximately 25 Myr and at a distance of just 320 - 360 pc, the combined late-type membership of the NGC 2232 and Cr 140 clusters will yield an almost unique sample of solar-type stars in the post-T Tauri/pre-main sequence phase of evolution. These stars will be used to assess the level and dispersion in coronal activity levels, as part of a probe of the importance of magnetic braking and the level of magnetic dynamo activity, for solar-type stars just before they reach the ZAMS. Over the past year we have successfully acquired all of the ground-based data necessary to support the analysis of the archival ROSAT X-ray data in the regions around both of these clusters. By the end of 2001 we expect to have completed the reduction and analysis of the ground-based photometry and spectroscopy and will begin the integration of these data with the ROSAT X-ray data. A certain amount of pressure to complete the work on NGC 2232 is coming from the SIRTF project, as this cluster may be a key component to a circumstellar disk evolution GTO program. We are only too happy to try to help and have worked to speed the analysis as much as possible. The primary activity to be undertaken in the next few months is the integration of the groundbased photometry and spectroscopy with the archival ROSAT X-ray data and then writing the paper summarizing our results. The most time consuming portion of this next phase is, of course, seeing the paper through publication in a peer-reviewed journal. Therefore, we have requested a no-cost extension to the grant to allow us to bring this project to a conclusion.

Patten, Brian M.↗
NASA NTRS1994

Tuning CAS Application using AIMS: An Automated Instrumentation and Monitoring System

To bring together NASA's scientists and engineers and their counterparts in industry, other government agencies, and academia working in the Computational AeroSciences (CAS) field. This workshop is part of the technology transfer plan of the High Performance Computing and Communications Program (HPCCP). Specific objectives of this Workshop are to: (1) communicate the goals and objectives of HPCCP in the area of CAS; (2) promote and disseminate CAS technology within the appropriate technical communities, including NASA, industry, academia, and other government labs; (3) help promote synergy among CAS scientists; and (4) permit feedback from peer researchers in issues pacing the CAS field in general and the HPCCP CAS program in particular.

Mehra, P.↗
NASA NTRS2001

"A Richness Study of 14 Distant X-Ray Clusters from the 160 Square Degree Survey"

We have measured the surface density of galaxies toward 14 X-ray-selected cluster candidates at redshifts z(sub i) 0.46, and we show that they are associated with rich galaxy concentrations. These clusters, having X-ray luminosities of Lx(0.5-2 keV) approx. (0.5 - 2.6) x 10(exp 44) ergs/ sec are among the most distant and luminous in our 160 deg(exp 2) ROSAT Position Sensitive Proportional Counter cluster survey. We find that the clusters range between Abell richness classes 0 and 2 and have a most probable richness class of 1. We compare the richness distribution of our distant clusters to those for three samples of nearby clusters with similar X-ray luminosities. We find that the nearby and distant samples have similar richness distributions, which shows that clusters have apparently not evolved substantially in richness since redshift z=0.5. There is, however, a marginal tendency for the distant clusters to be slightly poorer than nearby clusters, although deeper multicolor data for a large sample would be required to confirm this trend. We compare the distribution of distant X-ray clusters in the L(sub X)-richness plane to the distribution of optically selected clusters from the Palomar Distant Cluster Survey. The optically selected clusters appear overly rich for their X-ray luminosities, when compared to X-ray-selected clusters. Apparently, X-ray and optical surveys do not necessarily sample identical mass concentrations at large redshifts. This may indicate the existence of a population of optically rich clusters with anomalously low X-ray emission, More likely, however, it reflects the tendency for optical surveys to select unvirialized mass concentrations, as might be expected when peering along large-scale filaments.

Jones, Christine↗
NASA NTRS2002

High Resolution X-ray Imaging

NAG5-5020 covered a period of 7.5 years during which a great deal of progress was made in x-ray optical techniques under this grant. We survived peer review numerous times during the effort to keep the grant going. In 1994, when the grant started we were actively pursuing the application of spherical mirrors to improving x-ray telescopes. We had found that x-ray detectors were becoming rapidly more sophisticated and affordable, but that x-ray telescopes were only being improved through the intense application of money within the AXAF program. Clearly new techniques for the future were needed. We were successful in developing and testing at the HELSTF facility in New Mexico a four reflection coma-corrected telescope made from spheres. We were able to demonstrate 0.3 arcsecond resolution, almost to the diffraction limit of the system. The community as a whole was, at that time, not particularly interested in looking past AXAF (Chandra) and the effort needed to evolve. Since we had reached the diffraction limit using non-Wolter optics we then decided to see if we could build an x-ray interferometer in the laboratory. In the lab the potential for improved resolution was substantial. If synthetic aperture telescopes could be built in space, then orders of magnitude improvement would become feasible. In 1998 NASA, under the direction of Dr. Nick White of Goddard, started a study to assess the potential and feasibility of x-ray interferometry in space. My work became of central interest to the committee because it indicated that such was possible. In early 1999 we had the breakthrough that allowed us build a practical interferometer. By using flats and hooking up with the Marshall Space Flight Center facilities we were able to demonstrate fringes at 1.25keV on a one millimeter baseline. This actual laboratory demonstration provided the solid proof of concept that NASA needed.

Cash, Webster↗
NASA NTRS2002

Fidelity of the Integrated Force Method Solution

The theory of strain compatibility of the solid mechanics discipline was incomplete since St. Venant's 'strain formulation' in 1876. We have addressed the compatibility condition both in the continuum and the discrete system. This has lead to the formulation of the Integrated Force Method. A dual Integrated Force Method with displacement as the primal variable has also been formulated. A modest finite element code (IFM/Analyzers) based on the IFM theory has been developed. For a set of standard test problems the IFM results were compared with the stiffness method solutions and the MSC/Nastran code. For the problems IFM outperformed the existing methods. Superior IFM performance is attributed to simultaneous compliance of equilibrium equation and compatibility condition. MSC/Nastran organization expressed reluctance to accept the high fidelity IFM solutions. This report discusses the solutions to the examples. No inaccuracy was detected in the IFM solutions. A stiffness method code with a small programming effort can be improved to reap the many IFM benefits when implemented with the IFMD elements. Dr. Halford conducted a peer-review on the Integrated Force Method. Reviewers' response is included.

Hopkins, Dale↗
NASA NTRS2002

China as an Evolving Metro-Agro-Plex (China-MAP)

The one-year NASA-funded project was implemented to complete the analyses and model-simulations undertaken under the auspices of the 3-year research effort supported by NASA as an Interdisciplinary Earth System Science Investigation (IDS) entitled: China As An Evolving Metro-Agro-Plex (China-MAP). The primary goal of China-MAP was to assess the effects of economic development and the regional environmental changes it engenders upon agriculture in China. The project was carried out as part of the Sino-U.S. Science and Technology Protocol in the Atmospheric Sciences, an official government-to-government agreement that establishes the parameters for joint research projects between the two nations in the atmospheric sciences. The NASA-funded portion of the project focused on the development and application of a regional coupled climate/chemical transport model for East Asia (i.e., RegChem-CM). The funds provided under the subject 1-year project were used to: (1) complete specific investigations undertaken by the China-MAP Science Team using the Reg-Chem-CM expended; and (2) document the results of these and other China-MAP investigations in the peer-reviewed literature. A summary of these specific investigations in provided.

Chameides, William L.↗