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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 NTRS1987

Catalog of infrared observations. Part 1: Data

The Catalog of Infrared Observations (CIO) is a compilation of infrared astronomical observational data obtained from an extensive literature search of astronomical journals and major astronomical catalogs and surveys. The literature searches are complete for 1965 through 1986 in this Second Edition. The Catalog is published in two parts, with the observational data (roughly 200,000 observations of 20,000 individual sources) listed in Part I, and supporting appendices in Part II. The expanded Second Edition contains a new feature: complete IRAS 4-band data for all CIO sources detected, listed with the main Catalog observations, as well as in complete detail in the Appendix. The appendices include an atlas of infrared source positions, two bibliographies of infrared literature upon which the search was based, and, keyed to the main Catalog listings (organized alphabetically by author and then chronologically), an atlas of infrared spectral ranges, and IRAS data from the CIO sources. The complete CIO database is available to qualified users in printed microfiche and magnetic tape formats.

Gezari, Daniel Y.↗
NASA NTRS1988

Wind turbine acoustics research bibliography with selected annotation

Citations of documents are included, which represent the state-of-the-art of technology in each of the following acoustics subject areas: Prediction of Wind Turbine Noise; Acoustic Measurements for Wind Tunnels; Effect of Wind Turbine Noise on Building Structures, People and Communities; Atmospheric Propagation; and Measurement Technology Including Wind Screens. Documents are listed in chronological order in each section of the paper, with key documents and associated annotation listed first. The sources are given along with acquisition numbers, when available, to expedite the acquisition of copies of the documents.

Hubbard, Harvey H.↗
NASA NTRS1987

A perspective on 15 years of proof-of-concept aircraft development and flight research at Ames-Moffett by the Rotorcraft and Powered-Lift Flight Projects Division, 1970-1985

A proof-of-concept (POC) aircraft is defined and the concept of interest described for each of the six aircraft developed by the Ames-Moffet Rotorcraft and Powered-Lift Flight Projects Division from 1970 through 1985; namely, the OV-10, the C-8A Augmentor Wing, the Quiet Short-Haul Research Aircraft (QSRA), the XV-15 Tilt Rotor Research Aircraft (TRRA), the Rotor Systems Research Aircraft (RSRA)-compound, and the yet-to-fly RSRA/X-Wing Aircraft. The program/project chronology and most noteworthy features of the concepts are reviewed. The paper discusses the significance of each concept and the project demonstrating it; it briefly looks at what concepts are on the horizon as potential POC research aircraft and emphasizes that no significant advanced concept in aviation technology has ever been accepted by civilian or military users without first completing a demonstration through flight testing.

Few, David D.↗
NASA NTRS1988

The 1987 Airborne Antarctic Ozone Experiment: the Nimbus-7 TOMS Data Atlas

Total ozone data taken by the Nimbus-7 Total Ozone Mapping Spectrometer (TOMS) played a central role in the successful outcome of the 1987 Airborne Antarctic Ozone Experiment. The near-real-time TOMS total ozone observations were suppled within hours of real time to the operations center in Punta Arenas, Chile, over a telecommunications network designed specifically for this purpose. The TOMS data preparation and method of transfer over the telecommunications links are reviewed. This atlas includes a complete set of the near-real-time TOMS orbital overpass data over regions around the Palmer Peninsula of Antarctica for the period of August 8 through September 29, 1987. Also provided are daily polar orthographic projections of TOMS total ozone measurements over the Southern Hemisphere from August through November 1987. In addition, a chronology of the salient points of the experiment, along with some latitudinal cross sections and time series at locations of interest of the TOMS total ozone observations are presented. The TOMS total ozone measurements are evaluated along the flight tracks of each of the ER-2 and DC-8 missions during the experiment. The ozone hole is shown here to develop in a monotonic progression throughout late August and September. The minimum total ozone amount was found on 5 October, when its all-time lowest value of 109 DU is recorded. The hole remains well defined, but fills gradually from mid-October through mid-November. The hole's dissolution is observed here to begin in mid-November, when it elongates and begins to rotate. By the end of November, the south pole is no longer located within the ozone hole.

Krueger, Arlin J.↗
NASA NTRS1988

Experimental studies of vortex flows

This final report describes research work on vortex flows done during a four-year period beginning in March 1984 and funded by NASA Grant NCC2-294 from the Fluid Dynamics Research Branch of NASA Ames Research Center. After a brief introduction of the main topics addressed by the completed research, the accomplishments are summarized in chronological order.

Roberts, L.↗
NASA NTRS1988

Publications on acoustics research at the Langley Research Center during 1980-1986

This report is a compilation of publications from acoustics research at the Langley Research Center. The reports are listed in chronological order and summarize the written output of the Acoustics Division and its predecessor, The Acoustics and Noise Reduction Division, for the period 1980 through 1986. The information assembled has been extracted from the 1980 through 1986 issues for the Technical Memorandum entitled, Scientific and Technical Information Output of the Langley Research Center for the Calendar Year.

Sutherland, Linda W.↗
NASA NTRS1988

I-Xe systematics in LL chondrites

A stepwise heating analysis of Ar and Xe data from five neutron-irradiated whole rock LL chondrites (Soko Banja, Alta Ameen, Tuxtuac, Guidder, and Olivenza) is presented, emphasizing the complicated thermal history of ordinary chondrites. None of the present meteorites show a well-defined (Ar-40)-(Ar-39) apparent age plateau comprised of more than two release fractions. Most of the samples are found to yield well-defined high-temperature correlations between Xe-129/Xe-130 and Xe-128/Xe-130, and thus determinations of I-129/I-127 and Xe-129/Xe-130 at the time of isotopic closure for Xe. As in the case of other ordinary chondrites, the I-Xe systematics for LL chondrites correlate neither with a metamorphic grade nor with chronologies based opon other methods.

Bernatowicz, T. J.↗
NASA NTRS1988

Flood basalt volcanism during the past 250 million years

A chronology of the initiation dates of major continental flood basalt volcanism is established from published potassium-argon (K-Ar) and argon-argon (Ar-Ar) ages of basaltic rocks and related basic intrusions. The dating is therefore independent of the biostratigraphic and paleomagnetic time scales. Estimated errors of the initiation dates of the volcanic episodes determined from the distributions of the radiometric ages are, approximately, + or - 4 percent. There were 11 distinct episodes during the past 250 million years. Sometimes appearing in pairs, the episodes have occurred quasi-periodically with a mean cycle time of 32 + or - 1 (estimated error of the mean) million years. The initiation dates of the episodes are close to the estimated dates of mass extinctions of marine organisms. Showers of impacting comets may be the cause.

Rampino, Michael R.↗
NASA NTRS1988

Martian sample sites: Examples based on a global geologic perspective

Ten areas were selected that each include several rock units of varying lithology and age. These areas were chosen to optimize the geologic and chronologic data return from Mars. Geologic mapping and stratigraphic studies identify stratigraphic ages, rock types, and information on Martian geologic history that samples of a given site may yield. Volcanic rocks occur over much of the planet and in virtually all stratigraphic positions, and they are amenable to radioisotopic dating. Therefore, a reasonable and essential goal for a sample return mission is to return datable rocks from widely varying strata. Generally, about three or four major geologic units can be sampled at any of the given sites, most of which can probably be dated. The Mars Observer mission will aid greatly in interpreting lithology and defining contacts at the high resolution required to actually pinpoint good sample acquisition sites within these areas.

Scott, D. H.↗
NASA NTRS1988

Noble gases as tracers of the origin and evolution of the Martian atmosphere and the degassing history of the planet

Noble gas analysis of Martian samples can provide answers to a number of crucial questions. Some of the most obvious benefits will be in Martian chronology, using techniques that have been applied to lunar samples. However, these are by no means the only relevant noble gas studies possible. Since Mars has a substantial atmosphere, noble gases can be used to study the origin and evolution of that atmosphere, including the degassing history of the planet. This type of study can provide constraints on: (1) the total noble gas inventory of the planet, (2) the number of noble gas reservoirs existing, and (3) the exchange of gases between these reservoirs. How to achieve these goals are examined.

Swindle, T. D.↗
NASA NTRS1988

U-Th-Pb, Sm-Nd, Rb-Sr, and Lu-Hf systematics of returned Mars samples

The advantage of studying returned planetary samples cannot be overstated. A wider range of analytical techniques with higher sensitivities and accuracies can be applied to returned samples. Measurement of U-Th-Pb, Sm-Nd, Rb-Sr, and Lu-Hf isotopic systematics for chronology and isotopic tracer studies of planetary specimens cannot be done in situ with desirable precision. Returned Mars samples will be examined using all the physical, chemical, and geologic methods necessary to gain information on the origin and evolution of Mars. A returned Martian sample would provide ample information regarding the accretionary and evolutionary history of the Martian planetary body and possibly other planets of our solar system.

Tatsumoto, M.↗
NASA NTRS1989

Rotary balances: A selected, annotated bibliography

This bibliography on rotary balances contains 102 entries. It is part of NASA's support of the AGARD Fluid Dynamics Panel Working Group 11 on Rotary Balances. This bibliography includes works that might be useful to anyone interested in building or using rotor balances. Emphasis is on the rotary balance rigs and testing techniques rather than the aerodynamic data. Also included are some publications of historical interest which relate to key events in the development and use of rotary balances. The arrangement is chronological by date of publication in the case of reports and by presentation in the case of papers.

Tuttle, Marie H.↗
NASA NTRS1988

Flood basalt eruptions, comet showers, and mass extinction events

A chronology of initiation dates of the major continental flood basalt episodes has been established from compilation of published K-Ar and Ar-Ar ages of basaltic flows and related basic intrusions. The dating is therefore independent of the biostratigraphic and paleomagnetic time scales, and the estimated errors of the inititation dates are approximately + or - 4 pct. There are 11 distinct episodes of continental flood basalts known during the past 250 Myr. The data show that flood basalt episodes are generally relatively brief geologic events, with intermittent eruptions during peak output periods lasting ony 2 to 3 Myr or less. Statistical analyses suggest that these episodes may have occurred quasi-periodically with a mean cycle time of 32 + or - 1 Myr. The initiation dates of the flood basalts are close to the estimated dates of marine mass extinctions and impact-crater clusters. Although a purely internal forcing might be argued for the flood basalt volcanism, quasi-periodic comet impacts may be the trigger for both the flood basalts and the extinctions. Impact cratering models suggest that large-body impactors lead to deep initial cratering, and therefore may cause mantle disturbances and initiate mantle plume activity. The flood basalt episodes commonly mark the initiation or jump of a mantle hotspot, and are often followed by continental rifting and separation. Evidence from dynamical studies of impacts, occurrences of craters and hotspots, and the geochemistry of boundary layers is synthesized to provide a possible model of impact-generated volcanism. Flood basalt eruptions may themselves have severe effects on climate, and possibly on life. Impacts might, as a result, have led to mass extinctions through direct atmospheric disturbances, and/or indirectly through prolonged flood basalt volcanism.

Rampino, Michael R.↗
NASA NTRS1988

Tectonic setting of the Kolar Schist Belt, Karnataka, India

The tectonic setting of the Kolar Schist Belt and why the belt may represent a late Archean suture was discussed. The isotopic and chronological evidence that suggest diverse origins of the various packages of supracrustal rocks within the schist belt and the two gneiss terrains adjoining the belt were summarized. The eastern and western amphibolites were derived from sources at similar depths in the mantle (probably at similar ages, ca. 2.7 Ga), but these sources had distinct trace element compositions and histories. A distinctive feature of these differences was shown by the differences between the east and west amphibolites on a Ce vs. Nd diagram. In the gneisses the age and isotopic evidence suggest that the two terranes had distinct histories until after 2520 Ma and by 2420 Ma (Ar-40/Ar-39 age of muscovite in the sheared margin of the schist belt). Based on these data, the schist belt probably represents the site of accretion of diverse fragments (terrains) to the margin of the craton in the latest Archean, possibly as an Archean analog to the Phanerozoic North American Cordillera.

Hanson, G. N.↗
NASA NTRS1988

Future directions in meteorite research

Information presently available on meteorite composition and history and the areas in meteorite research that should be covered in future in order to shed additional light on the earliest history of the solar system are discussed. Attention is given to the work needed in the classification schemes for chondrites, the question of the identification of parent bodies of the major meteorite and chondrite types, the igneous differentiation of certain asteroids, the effects of irradiation, the solar-system chronology, and issues concerning the early solar system. Other important areas discussed include the elemental composition of chondrites, the magnetic properties of meteorites, the composition and the petrology of chondrules, the properties of primitive material surviving in chondrites, the micrometeorites, the nebula, the presolar material in meteorites, the nucleosynthesis, and the nucleocosmochronology.

Anders, E.↗
NASA NTRS1987

Age-related disappearance of Mayer-like heart rate waves

The effect of age on the principal spectral components of heart rate obtained immediately after passive upright tilt was investigated in human subjects who underwent a 60-deg tilt over 9 sec. Two groups were examined, the first of which consisting of healthy male subjects aged 22-26 years, while the second was comprised of subjects aged 65-84 years on no medication; radiograms were recorded continuously beginning just prior to tilt until 3 min posttilt. The results of spectral analysis showed that elderly subjects did not exhibit the Mayer-like heart rate waves (the 0.07-0.09 Hz oscillations) that were present in the spectra of young subjects immediately after passive upright tilt. The findings are consistent with the concept of a 'dysautonomia of aging'. It is suggested that postural stress testing with spectral analysis of heart rate fluctuations may provide a useful way of assessing physiologic vs chronologic age.

Jarisch, W. R.↗
NASA NTRS1989

The impact history of the solar system - Implications for the origins of atmospheres

The present consideration of the roles played by impacts in the origin and evolution of planetary and satellite atmospheres notes that while small impacts of volatile-rich planetesimals can contribute to a body's volatile inventory, large impacts blow away existing primordial atmospheres and generate main-body outgassing; these processes would have been in greatest competition during the end-stage of accretion. The uncertainties in solar system cratering-record interpretation and event-chronology yield only order-of-magnitude estimates. Temporal fluctuations in the impact rate may be very large, notably in the case of cometary sources, where a factor-of-2 variation is common, and a factor-of-100 variation is entirely possible.

Weissman, P. R.↗
NASA NTRS1990

Scheduling Nonconsumable Resources

Users manual describes computer program SWITCH that schedules use of resources - by appliances switched on and off and use resources while they are on. Plans schedules according to predetermined goals; revises schedules when new goals imposed. Program works by depth-first searching with strict chronological back-tracking. Proceeds to evaluate alternatives as necessary, sometimes interacting with user.

Porta, Harry J.↗