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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS2000

STS-99 Payload Bay Door Opening at Pad 39A Endeavour

The primary objective of the STS-99 mission was to complete high resolution mapping of large sections of the Earth's surface using the Shuttle Radar Topography Mission (SRTM), a specially modified radar system. This videotape shows the doors to the payload bay opening prior to the emplacement of the SRTM. It also shows views of the personnel in the clean room during the process.

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NASA NTRS1991

STS-40/SLS-1: Lift to Cargo Bay

The footage shows the lifting of the solid state micro-accelerometer into Colombia's cargo bay. This was done in a clean room setting and is part of the In Orbit Technology Demonstration Program.

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NASA NTRS1990

STS-41: Discovery Payload Bay Door Investigation

The brief footage shows the visual inspection of the bay door by 2 technicians. They inspect the layers between the panels for structural defects, and the door, joints, and hinges for wear, cracks, stress, and damage from flight.

Source record↗
NASA NTRS1992

STS-54 TDRS-F in Cargo Bay at Pad B

Footage shows close-up shots of the Tracking and Data Relay Satellite (TDRS) in the Endeavour Orbiter's cargo bay at Launch Pad B.

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NASA NTRS2001

Narragansett Bay From Space: A Perspective for the 21st Century

In 1996, the NASA Administrator Dan Goldin and Rhode Island Congressman Patrick Kennedy challenged researchers in the Department of Geological Sciences at Brown University to developed a series of projects to apply remotely sensed data to problems of immediate concern to the State of Rhode Island. The result of that challenge was the project Narragansett Bay from Space: A Perspective for the 21st Century. The goals of the effort were to a) identify problems in coordination with state and local agencies, b) apply NASA technology to the problems and c) to involve small business that would benefit from incorporating remotely sensed data into their business operations. The overall effort was to serve two functions: help provide high quality science results based on remotely sensed data and increase the capacity of environmental managers and companies to use remotely sensed data. The effort has succeeded on both these fronts by providing new, quantitative information on the extent of environmental problems and developing a greater awareness and acceptance of remotely sensed data as a tool for monitoring and research.

Mustard, John F.↗
NASA NTRS1994

Analysis of Crew Fatigue in AIA Guantanamo Bay Aviation Accident

Flight operations can engender fatigue, which can affect flight crew performance, vigilance, and mood. The National Transportation Safety Board (NTSB) requested the NASA Fatigue Countermeasures Program to analyze crew fatigue factors in an aviation accident that occurred at Guantanamo Bay, Cuba. There are specific fatigue factors that can be considered in such investigations: cumulative sleep loss, continuous hours of wakefulness prior to the incident or accident, and the time of day at which the accident occurred. Data from the NTSB Human Performance Investigator's Factual Report, the Operations Group Chairman's Factual Report, and the Flight 808 Crew Statements were analyzed, using conservative estimates and averages to reconcile discrepancies among the sources. Analysis of these data determined the following: the entire crew displayed cumulative sleep loss, operated during an extended period of continuous wakefulness, and obtained sleep at times in opposition to the circadian disposition for sleep, and that the accident occurred in the afternoon window of physiological sleepiness. In addition to these findings, evidence that fatigue affected performance was suggested by the cockpit voice recorder (CVR) transcript as well as in the captain's testimony. Examples from the CVR showed degraded decision-making skills, fixation, and slowed responses, all of which can be affected by fatigue; also, the captain testified to feeling "lethargic and indifferent" just prior to the accident. Therefore, the sleep/wake history data supports the hypothesis that fatigue was a factor that affected crewmembers' performance. Furthermore, the examples from the CVR and the captain's testimony support the hypothesis that the fatigue had an impact on specific actions involved in the occurrence of the accident.

Rosekind, Mark R.↗
NASA NTRS1989

Lipophilic pigments from cyanobacterial (blue-green algal) and diatom mats in Hamelin Pool, Shark Bay, Western Australia

Lipophilic pigments were examined in microbial mat communities dominated by cyanobacteria in the intertidal zone and by diatoms in the subtidal and sublittoral zones of Hamelin Pool, Shark Bay, Western Australia. These microbial mats have evolutionary significance because of their similarity to lithfied stromatolites from the Proterozoic and Early Paleozoic eras. Fucoxanthin, diatoxanthin, diadinoxanthin, beta-carotene, and chlorophylls a and c characterized the diatom mats, whereas cyanobacterial mats contained myxoxanthophyll, zeaxanthin, echinenone, beta-carotene, chlorophyll a and, in some cases, sheath pigment. The presence of bacteriochlorophyll a within the mats suggest a close association of photosynthetic bacteria with diatoms and cyanobacteria. The high carotenoids : chlorophyll a ratios (0.84-2.44 wt/wt) in the diatom mats suggest that carotenoids served a photoprotective function in this high light environment. By contrast, cyanobacterial sheath pigment may have largely supplanted the photoprotective role of carotenoids in the intertidal mats.

NASA Discipline Exobiology↗
NASA NTRS1988

Microfossils from oolites and pisolites of the Upper Proterozoic Eleonore Bay Group, Central East Greenland

Silicified oolites and pisolites from Bed 18 of the Upper Proterozoic (about 700-800 Ma) Limestone-Dolomite "Series" of the Eleonore Bay Group, central East Greenland, contain a diverse suite of organically preserved microfossils that is, for the most part. [Of the] assemblages previously described from Proterozoic cherts and shales. Three principal assemblages occur in these rocks: 1) a class bound assemblage found in detrital carbonate grains (now silicified) that served as nuclei for ooid and pisoid growth, as well as in uncoated mud and mat clasts that were carried into the zone of ooid and pisoid deposition; 2) an epilithic and interstitial assemblage consisting of microorganisms that occurred on top of and between grains; and 3) a euendolithic assemblage composed of microbes that actively bored into coated grains. The Upper Proterozoic euendolithic assemblage closely resembles a community of euendolithic cyanobacteria found today in shallow marine ooid sands of the Bahama Banks. Thirteen species are described, of which eight are new, five representing new genera: Eohyella dichotoma n. sp., Eohyella endoatracta n. sp., Eohyella rectoclada n. sp., Thylacocausticus globorum n. gen. and sp., Cunicularius halleri n. gen. and sp., Graviglomus incrustus n. gen. and sp., Perulagranum obovatum n. gen. and sp., and Parenchymodiscus endolithicus n. gen. and sp.

NASA Discipline Exobiology↗
NASA NTRS2005

Osmium-Isotope and Platinum-Group-Element Systematics of Impact-Melt Rocks, Chesapeake Bay Impact Structure, Virginia, USA

Osmium (Os) isotopes and platinum-group elements (PGEs) are useful for geochemically identifying a meteoritic component within impact structures, because meteorites are typically characterized by low (187)Os/(188)Os ratios and high PGE concentrations. In contrast, most types of crustal target rocks have high radiogenic Os and very low PGE concentrations. We have examined Os isotope and PGE systematics of impact-melt rocks and pre-impact target rocks from a 2004 test hole in the late Eocene Chesapeake Bay impact structure and from nearby coreholes. Our goal is to determine the proportion of the projectile component in the melt rock Additional information is included in the original extended abstract.

Lee, Seung Ryeol↗
NASA NTRS2005

Spatial Predictive Modeling and Remote Sensing of Land Use Change in the Chesapeake Bay Watershed

This project was focused on modeling the processes by which increasing demand for developed land uses, brought about by changes in the regional economy and the socio-demographics of the region, are translated into a changing spatial pattern of land use. Our study focused on a portion of the Chesapeake Bay Watershed where the spatial patterns of sprawl represent a set of conditions generally prevalent in much of the U.S. Working in the region permitted us access to (i) a time-series of multi-scale and multi-temporal (including historical) satellite imagery and (ii) an established network of collaborating partners and agencies willing to share resources and to utilize developed techniques and model results. In addition, a unique parcel-level tax assessment database and linked parcel boundary maps exists for two counties in the Maryland portion of this region that made it possible to establish a historical cross-section time-series database of parcel level development decisions. Scenario analyses of future land use dynamics provided critical quantitative insight into the impact of alternative land management and policy decisions. These also have been specifically aimed at addressing growth control policies aimed at curbing exurban (sprawl) development. Our initial technical approach included three components: (i) spatial econometric modeling of the development decision, (ii) remote sensing of suburban change and residential land use density, including comparisons of past change from Landsat analyses and more traditional sources, and (iii) linkages between the two through variable initialization and supplementation of parcel level data. To these we added a fourth component, (iv) cellular automata modeling of urbanization, which proved to be a valuable addition to the project. This project has generated both remote sensing and spatially explicit socio-economic data to estimate and calibrate the parameters for two different types of land use change models and has undertaken analyses of these models. One (the CA model) is driven largely by observations on past patterns of land use change, while the other (the EC model) is driven by mechanisms of the land use change decision at the parcel level. Our project may be the first serious attempt at developing both types of models for the same area, using as much common data as possible. We have identified the strengths and weaknesses of the two approaches and plan to continue to revise each model in the light of new data and new lessons learned through continued collaboration. Questions, approaches, findings, publication and presentation lists concerning the research are also presented.

Goetz, Scott J.↗
NASA NTRS2005

Multisensor Observation and Simulation of Snowfall During the 2003 Wakasa Bay Field Experiment

This research seeks to assess and improve the accuracy of microphysical assumptions used in satellite passive microwave radiative transfer models and retrieval algorithms by exploiting complementary observations from satellite radiometers, such as TRMM/AMSR-E/GPM, and coincident aircraft instruments, such as the next generation precipitation radar (PR-2). We focus in particular on aircraft data obtained during the Wakasa Bay field experiment, Japan 2003, pertaining to surface snowfall events. The observations of vertical profiles of reflectivity and Doppler-derived fall speeds are used in conjunction with the radiometric measurements to identify 1-D profiles of precipitation particle types, sizes, and concentrations that are consistent with the observations.

Johnson, Benjamin T.↗