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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 NTRS1998

The Physics of Hard Spheres Experiment on MSL-1: Required Measurements and Instrument Performance

The Physics of HArd Spheres Experiment (PHaSE), one of NASA Lewis Research Center's first major light scattering experiments for microgravity research on complex fluids, flew on board the Space Shuttle's Microgravity Science Laboratory (MSL-1) in 1997. Using colloidal systems of various concentrations of micron-sized plastic spheres in a refractive index-matching fluid as test samples, illuminated by laser light during and after crystallization, investigations were conducted to measure the nucleation and growth rate of colloidal crystals as well as the structure, rheology, and dynamics of the equilibrium crystal. Together, these measurements support an enhanced understanding of the nature of the liquid-to-solid transition. Achievement of the science objectives required an accurate experimental determination of eight fundamental properties for the hard sphere colloidal samples. The instrument design met almost all of the original measurement requirements, but with compromise on the number of samples on which data were taken. The instrument performs 2-D Bragg and low angle scattering from 0.4 deg. to 60 deg., dynamic and single-channel static scattering from 10 deg. to 170 deg., rheology using fiber optics, and white light imaging of the sample. As a result, PHaSE provided a timely microgravity demonstration of critical light scattering measurement techniques and hardware concepts, while generating data already showing promise of interesting new scientific findings in the field of condensed matter physics.

Doherty, Michael P.↗
NASA NTRS1999

Measurements of Nucleation-Mode Particle Size Distributions in Aircraft Plumes during SULFUR 6

This report summarizes the participation of the University of Denver in an airborne measurement program, SULFUR 6, which was undertaken in late September and early October of 1998 by the Deutsches Zentrum fur Luft und Raumfahrt (DLR). Scientific findings from two papers that have been published or accepted and from one manuscript that is in preparation are presented. The SULFUR 6 experiment was designed to investigate the emissions from subsonic aircraft to constrain calculations of possible atmospheric chemical and climatic effects. The University of Denver effort contributed toward the following SULFUR 6 goals: (1) To investigate the relationship between fuel sulfur content (FSC--mass of sulfur per mass of fuel) and particle number and mass emission index (El--quantity emitted per kg of fuel burned); (2) To provide upper and lower limits for the mass conversion efficiency (nu) of fuel sulfur to gaseous and particulate sulfuric acid; (3) To constrain models of volatile particle nucleation and growth by measuring the particle size distribution between 3 and 100 nm at aircraft plume ages ranging from 10(exp -1) to 10(exp 3) s; (4) To determine microphysical and optical properties and bulk chemical composition of soot particles in aircraft exhaust; and (5) To investigate the differences in particle properties between aircraft plumes in contrail and non-contrail situations. The experiment focused on emissions from the ATTAS research aircraft (a well characterized, but older technology turbojet) and from an in-service Boeing 737-300 aircraft provided by Lufthansa, with modem, high-bypass turbofan engines. Measurements were made from the DLR Dassault Falcon 900 aircraft, a modified business jet. The Atmospheric Effects of Aviation Program (AEAP) provided funding to operate an instrument, the nucleation-mode aerosol size spectrometer (N-MASS), during the SULFUR 6 campaign and to analyze the data. The N-MASS was developed at the University of Denver with the support of NOAA's Office of Global Programs and NASA's AEAP and measures particle size distributions in the 4-100 nm range.

Brock, Charles A.↗
NASA NTRS1996

Evaluating Fatigue in Operational Settings: The NASA Ames Fatigue Countermeasures Program

In response to a 1980 Congressional request, NASA Ames initiated a program to examine fatigue in flight operations. The Program objectives are to examine fatigue, sleep loss, and circadian disruption in flight operations, determine the effects of these factors on flight crew performance, and the development of fatigue countermeasures. The NASA Ames Fatigue Countermeasures Program conducts controlled laboratory experiments, full-mission flight simulations, and field studies. A range of subjective, behavioral, performance, physiological, and environmental measures are used depending on study objectives. The Program has developed substantial expertise in gathering data during actual flight operations and in other work settings. This has required the development of ambulatory and other measures that can be carried throughout the world and used at 41,000 feet in aircraft cockpits. The NASA Ames Fatigue Countermeasures Program has examined fatigue in shorthaul, longhaul, overnight cargo, and helicopter operations. A recent study of planned cockpit rest periods demonstrated the effectiveness of a brief inflight nap to improve pilot performance and alertness. This study involved inflight reaction time/vigilance performance testing and EEG/EOG measures of physiological alertness. The NASA Ames Fatigue Countermeasures Program has applied scientific findings to the development of education and training materials on fatigue countermeasures, input to federal regulatory activities on pilot flight, duty, and rest requirements, and support of National Transportation Safety Board accident investigations. Current activities are examining fatigue in nonaugmented longhaul flights, regional/commuter flight operations, corporate/business aviation, and psychophysiological variables related to performance.

Rosekind, Mark R.↗
NASA NTRS1997

Sleep and Rest Requirements: Physiological Considerations

Sleep is a vital physiological need which must be met to insure optimal functioning. A single night of significantly shortened sleep negatively impacts performance, alertness, and mood. Restricted sleep studies have shown that even a relatively small amount of sleep loss over several consecutive days can be additive and result in a cumulative sleep debt with similar detrimental effects. Compounding the problem of sleep loss in the operational environment is the poor correlation between subjective reports of sleepiness and objective measures of physiological sleep need. Some of the factors determining how sleepy an individual is at a given point in time are: (1) individual characteristics (e.g., amount of prior sleep and wakefulness, circadian phase, age), (2) environmental conditions (e.g., noise, temperature, amount of social interaction), and (3) task variables (e.g., signal rate, workload). Although sleep need can be masked with medications, the only way to reduce it is with sleep itself. The timing of the sleep period can affect sleep duration and quality and thus its restorative strength. The data are clear that increasing sleep time results in improved alertness. This paper will briefly review the scientific findings on sleep need, the effects of sleep loss, napping strategies, and the implications of incorporating physiologically sound sleep and rest strategies into the operational aviation environment.

Neri, David F.↗
NASA NTRS2003

SHADOZ (Southern Hemisphere Additional Ozonesondes): A Tropical Ozonesonde-Radiosonde Network for the Atmospheric Community

A lack of sounding data has limited the accuracy of ozone satellite retrievals in the tropics and our understanding of chemical-dynamical interactions in a region strongly influenced by natural variability and anthropogenic activity. In 1998, NASA s Goddard Space Flight Center, NOAA's Climate Monitoring and Diagnostics Laboratory (CMDL) and a team of international sponsors established the SHADOZ (Southern Hemisphere ADditional OZonesondes) project to address the gap in tropical ozone soundings. SHADOZ augments launches at selected sites and provides a public archive of ozonesonde and radiosonde data from twelve tropical and subtropical stations at http://croc.gsfc.nasa.gov/shadoz. Instrumentation, data and a summary of the first scientific findings from SHADOZ are presented.

Thompson, Anne M.↗
NASA NTRS2004

Acquisition and Analysis of NASA Ames Sunphotometer Measurements during SAGE III Validation Campaigns and other Tropospheric and Stratospheric Research Missions

NASA Cooperative Agreement NCC2-1251 provided funding from April 2001 through December 2003 for Mr. John Livingston of SRI International to collaborate with NASA Ames Research Center scientists and engineers in the acquisition and analysis of airborne sunphotometer measurements during various atmospheric field studies. Mr. Livingston participated in instrument calibrations at Mauna Loa Observatory, pre-mission hardware and software preparations, acquisition and analysis of sunphotometer measurements during the missions, and post-mission analysis of data and reporting of scientific findings. The atmospheric field missions included the spring 2001 Intensive of the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia), the Asian Dust Above Monterey-2003 (ADAM-2003) experiment, and the winter 2003 Second SAGE III Ozone Loss and Validation Experiment (SOLVE II).

Livingston, John M.↗
NASA NTRS2003

Research on TRMM and GPM Through Collaboration Between JAXA & NASA

The Japan Aerospace Exploration Agency (JAXA) is conducting joint research with the Communications Research Laboratory (CRL) and the National Aeronautics and Space Administration (NASA) on a new constellation satellite observation project called Global Precipitation Measurement (GPM), the main satellite of which is planned for launch in 2008 by JAXA. This GPM project was proposed as a follow-up mission to the Tropical Rainfall Measuring Mission (TRMM) by both the Japanese and American sides based on the unparalleled scientific success of TRMM. A major reason for TRMM's success was the use of the worlds first spaceborne rain radar, the Precipitation Radar (PR) system developed by the National Space Development Agency of Japan (NASDA, now JAXA) and CRL. Measurements from this instrument have ushered in many new scientific findings and have opened a new era of precipitation measuring from space. GPM is an ambitious project which will produce accurate and frequent global observations of precipitation (both rain and snow) made possible by replacing TRMM with a new core satellite carrying an advanced radar-radiometer system, and serving as the centerpiece for a constellation of some eight (8) additional satellites being provided through international cooperation. The core satellite is to be flown up to high latitudes (inclined some 65-70 degrees), and will carry a dual-frequency precipitation radar (DPR) that will be newly developed by JAXA and CRL, along with a large aperture, extended frequency-range passive microwave radiometer being provided by NASA. Each constellation satellite will also carry some type of multi-channel passive microwave radiometer whose rain estimates will be calibrated and referenced to those made by the core satellite, producing for the first time fully-global, continuous, and bias-free precipitation datasets. GPM data will be delivered in near-realtime, taking a major step toward the operational use of precipitation information for model initialization and data assimilation in a number of application areas such as hazardous weather forecasting, flood warning, fresh water resource assessment, and crop growth prediction. In addition, GPM data will complement the now-existing global temperature record, allowing for improved assessments of climate change, particularly those processes in which the global water cycle both forces and responds to climatic drifts in global temperature conditions.

Smith, Eric A.↗
NASA NTRS2004

Dust Properties in Comets and Protoplanetary Disks

Our fundamental science goal is to characterize the connections between grain (siliceous and carbonaceous) mineralogy and the origins and evolution of disks and protoplanetesimals. To achieve this goal, we proposed a cooperative agreement which was divided into two separate yet complementary work efforts: 1) the study of solar system comets and 2) the study of dusty protoplanetary disks. In this final report we look at the goals achieved in each of these efforts and compare them with our initial stated goals. We also highlight our scientific findings accomplished under this JRI work effort.

Wooden, Diane H.↗
NASA NTRS1996

Managing fatigue in operational settings. 1: Physiological considerations and countermeasures

The authors consider three aspects of managing fatigue in the workplace. They provide a brief overview of important scientific findings related to sleep and circadian physiology that establish the psychobiological foundation of fatigue. Their major focus is on the relevance of these findings to operational settings. In addition, they provide examples to describe practical fatigue countermeasures that can be used in operational settings.

Review, Tutorial↗
NASA NTRS2006

Status and Plans for the WCRP/GEWEX Global Precipitation Climatology Project (GPCP)

Status and plans for GPCP are presented along with scientific findings from the current data set. Global and large regional rainfall variations and possible long-term changes are examined using the 26-year (1979-2004) monthly dataset from the Global Precipitation Climatology Project (GPCP). One emphasis is to discriminate among the variations due to ENSO, volcanic events and possible long-term changes. Although the global change of precipitation in the data set is near zero, the data set does indicate an upward trend (0.13 mm/day/25yr) and a downward trend (-0.06 mm/day/25yr) over tropical oceans and lands (25S-25N), respectively. This corresponds to a 4% increase (ocean) and 2% decrease (land) during this time period. Simple techniques are derived to attempt to eliminate variations due to ENSO and major volcanic eruptions in the Tropics. Using only annual values two "volcano years" are determined by examining ocean-land coupled variations in precipitation related to ENSO and other phenomena. The outlier years coincide with Pinatubo and El Chicon eruptions. The ENSO signal is reduced by deriving mean ocean and land values for El Nino, La Nina and neutral conditions based on Nino 3.4 SST and normalizing the annual ocean and land precipitation to the neutral set of cases. The impact of the two major volcanic eruptions over the past 25 years is estimated to be about a 5% reduction in tropical rainfall. The modified data set (with ENSO and volcano effect at least partially removed) retains the same approximate linear change slopes over the data set period, but with reduced variance leading to significance tests with results in the 90-95% range. Intercomparisons between the GPCP, SSM/I (1988-2004), and TRMM (1998-2004) satellite rainfall products and alternate gauge analyses over land are made to attempt to increase or decrease confidence in the changes seen in the GPCP analysis.

Adkerm Robert F.↗
NASA NTRS2006

JPL Missions Overview

This viewgraph reviews the current missions that JPL is managing for NASA. Specifically it reviews JPL's capabilities end-to-end to implement missions, development of research and technology. It includes information on JPL's vision for space exploration and JPL's current missions It reviews the recent scientific findings. Lastly, the presentation gives an overview of the Mars Science Laboratory Mission.

flight missions↗
NASA NTRS2006

Status of Current and Future Remote Sensing with EO-1 Hyperion

The Earth Observing-One (EO-1) satellite, launched in November of 2000, will complete six full years of operation near the end of this year. Observations from the Hyperion Imaging Spectrometer on board EO-1 have contributed to over 300 papers in refereed journals, conference proceeds and other presentations. Hyperion has been used to study a variety of natural and anthropogenic phenomena including hazards and catastrophes, agricultural health and productivity, ecological disturbance/development, and land use/land cover change. As an example, Hyperion has been used in hazard and catastrophe studies to monitor and assess effects of tsunamis, earthquakes, volcanic eruptions, mudslides, tornadoes, hurricanes, wild-fires (natural and human ignited), oil spills, and the aftermath of world trade center bombing. This presentation summarizes the current status of EO-1 Hyperion in terms of key scientific findings to date and future plans for operation of this instrument through 2007.

Ungar, Stephen↗
NASA NTRS2010

Leading the Public Face of Space

The National Aeronautics and Space Administration (NASA) is fully committed to sharing the excitement of America's international space missions with its stakeholders, particularly the general public. In 2009, the Space Shuttle delivered astronauts to the Hubble Space Telescope to service that great observatory and to the International Space Station to install the observation platform on the Japanese Kibo laboratory. The Lunar Reconnaissance Orbiter is showing an unprecedented view of the Moon, confirming the presence of hardware left behind during the Apollo missions decades ago and helping scientists better understand Earth's natural satellite. These and numerous other exciting missions are fertile subjects for public education and outreach. NASA's core mission includes engaging the public face of space in many forms and forums. Agency goals include communicating with people across the United States and through international opportunities. NASA has created a culture where communication opportunities are valued avenues to deliver information about scientific findings and exploration possibilities. As this presentation will show, NASA's leaders act as ambassadors in the public arena and set expectations for involvement across their organizations. This presentation will focus on the qualities that NASA leaders cultivate to achieve challenging missions, to expand horizons and question "why". Leaders act with integrity and recognize the power of the team multiplier effect on delivering technical performance within budget and schedule, as well as through participation in education and outreach opportunities. Leaders are responsible for budgeting the resources needed to reach target audiences with compelling, relevant information and serve as role models, delivering key messages to various audiences. Examples that will be featured in this presentation include the Student Launch Projects and Great Moonbuggy race, which reach hundreds of students who are a promising pipeline for new scientists and engineers for a new generation of discovery. The popular Exploration Experience trailer is an interactive-exhibit environment that travels across the United States, conveying the innovation necessary for space travel and the wonder of discovery that comes from viewing our planet as part of the larger space-scape.

Dumbacher, Daniel L.↗
NASA NTRS2009

Leading the Public Face of Space

The National Aeronautics and Space Administration (NASA) is fully committed to sharing the excitement of America's international space missions with its stakeholders, particularly the general public. In 2009, the Space Shuttle delivered astronauts to the Hubble Space Telescope to service that great observatory and to the International Space Station to install the observation platform on the Japanese Kibo laboratory. The Lunar Reconnaissance Orbiter is showing an unprecedented view of the Moon, confirming the presence of hardware left behind during the Apollo missions decades ago and helping scientists better understand Earth's natural satellite. These and numerous other exciting missions are fertile subjects for public education and outreach. NASA's core mission includes engaging the public face of space in many forms and forums. Agency goals include communicating with people across the United States and through international opportunities. NASA has created a culture where communication opportunities are valued avenues to deliver information about scientific findings and exploration possibilities. As this presentation will show, NASA's leaders act as ambassadors in the public arena and set expectations for involvement across their organizations. This presentation will focus on the qualities that NASA leaders cultivate to achieve challenging missions, to expand horizons and question "why". Leaders act with integrity and recognize the power of the team multiplier effect on delivering technical performance within budget and schedule, as well as through participation in education and outreach opportunities. Leaders are responsible for budgeting the resources needed to reach target audiences with compelling, relevant information and serve as role models, delivering key messages to various audiences. Examples that will be featured in this presentation include the Student Launch Projects and Great Moonbuggy race, which reach hundreds of students who are a promising pipeline for new scientists and engineers for a new generation of discovery. The popular Exploration Experience trailer is an interactive-exhibit environment that travels across the United States, conveying the innovation necessary for space travel and the wonder of discovery that comes from viewing our planet as part of the larger space-scape.

Dumbacher, Daniel L.↗
NASA NTRS2010

Australian Soil Moisture Field Experiments in Support of Soil Moisture Satellite Observations

Large-scale field campaigns provide the critical fink between our understanding retrieval algorithms developed at the point scale, and algorithms suitable for satellite applications at vastly larger pixel scales. Retrievals of land parameters must deal with the substantial sub-pixel heterogeneity that is present in most regions. This is particularly the case for soil moisture remote sensing, because of the long microwave wavelengths (L-band) that are optimal. Yet, airborne L-band imagers have generally been large, heavy, and required heavy-lift aircraft resources that are expensive and difficult to schedule. Indeed, US soil moisture campaigns, have been constrained by these factors, and European campaigns have used non-imagers due to instrument and aircraft size constraints. Despite these factors, these campaigns established that large-scale soil moisture remote sensing was possible, laying the groundwork for satellite missions. Starting in 2005, a series of airborne field campaigns have been conducted in Australia: to improve our understanding of soil moisture remote sensing at large scales over heterogeneous areas. These field data have been used to test and refine retrieval algorithms for soil moisture satellite missions, and most recently with the launch of the European Space Agency's Soil Moisture Ocean Salinity (SMOS) mission, to provide validation measurements over a multi-pixel area. The campaigns to date have included a preparatory campaign in 2005, two National Airborne Field Experiments (NAFE), (2005 and 2006), two campaigns to the Simpson Desert (2008 and 2009), and one Australian Airborne Cal/val Experiment for SMOS (AACES), just concluded in the austral spring of 2010. The primary airborne sensor for each campaign has been the Polarimetric L-band Microwave Radiometer (PLMR), a 6-beam pushbroom imager that is small enough to be compatible with light aircraft, greatly facilitating the execution of the series of campaigns, and a key to their success. An L-band imaging radar is being added to the complement to provide simultaneous active-passive L-band observations, for algorithm development activities in support of NASA's upcoming Soil Moisture Active Passive (.S"M) mission. This paper will describe the campaigns, their objectives, their datasets, and some of the unique advantages of working with small/light sensors and aircraft. We will also review the main scientific findings, including improvements to the SMOS retrieval algorithm enabled by NAFE observations and the evaluation of the Simpson Desert as a calibration target for L-band satellite missions. Plans for upcoming campaigns will also be discussed.

Kim, Edward↗
NASA NTRS2000

An Integrated Exploration Strategy

Many new scientific findings in planetary science (potential life in a Mars meteorite, possible frozen water at the Lunar Poles, permanently lit region at the lunar south pole, recent water flow on Mars) provide a compelling case for humans to once again leave low earth orbit and explore. Robotic missions are capable of conducting science, but only humans can explore and discover. The challenge is to build an affordable exploration program. This can be done by aggressively evolving our current systems, developing high payoff technologies, leveraging off commercial and other agencies' programs, and developing a set of core capabilities to be used to explore a variety of destinations. NASA has a Strategic Roadmap based on detailed mission studies to develop these core technologies and capabilities to allow human space exploration. Advances in human support, launch vehicle. improvements, development of in-space transportation systems, efficient power generation and distribution, and In-Situ Resource Utilization are all required to meet the exploration challenge. The groundwork today will provide the technology and tools needed to conduct safe, affordable, and efficient exploration to the moon, asteroids, deep space observatories and Mars.

Conley, Mike↗
NASA NTRS2008

Hubble 2007: Science Year in Review

This book epitomizes Hubbles continuing years of glorious accomplishments, presenting a sample of the activities, operations and observations, and scientific findings from 2007. Here is our observatory. Here are a few of our talented people. Here is what we have done. NASA plans a final servicing mission to Hubble in 2008. Two powerful new instruments are to be installed, and repairs made. After the astronauts do their wonderful work, Hubble will be more capable than at any time since launch. The science community eagerly anticipates the new opportunities for research offered by a refurbished observatory. While we do not know exactly what new science stories will appear in future editions of this book, we are certain that the frontiers of science will continue to be pushed outward by the forces of human curiosity and cleverness, channeled by the Hubble Space Telescope.

Hubble space telescope↗
NASA NTRS2013

From BASE-ASIA Toward 7-SEAS: A Satellite-Surface Perspective of Boreal Spring Biomass-Burning Aerosols and Clouds in Southeast Asia

In this paper, we present recent field studies conducted by NASA's SMART-COMMIT (and ACHIEVE, to be operated in 2013) mobile laboratories, jointly with distributed ground-based networks (e.g., AERONET, http://aeronet.gsfc.nasa.gov/ and MPLNET, http://mplnet.gsfc.nasa.gov/) and other contributing instruments over northern Southeast Asia. These three mobile laboratories, collectively called SMARTLabs (cf. http://smartlabs.gsfc.nasa.gov/, Surface-based Mobile Atmospheric Research & Testbed Laboratories) comprise a suite of surface remote sensing and in-situ instruments that are pivotal in providing high spectral and temporal measurements, complementing the collocated spatial observations from various Earth Observing System (EOS) satellites. A satellite-surface perspective and scientific findings, drawn from the BASE-ASIA (2006) field deployment as well as a series of ongoing 7-SEAS (2010-13) field activities over northern Southeast Asia are summarized, concerning (i) regional properties of aerosols from satellite and in situ measurements, (ii) cloud properties from remote sensing and surface observations, (iii) vertical distribution of aerosols and clouds, and (iv) regional aerosol radiative effects and impact assessment. The aerosol burden over Southeast Asia in boreal spring, attributed to biomass burning, exhibits highly consistent spatial and temporal distribution patterns, with major variability arising from changes in the magnitude of the aerosol loading mediated by processes ranging from large-scale climate factors to diurnal meteorological events. Downwind from the source regions, the tightly coupled-aerosolecloud system provides a unique, natural laboratory for further exploring the micro- and macro-scale relationships of the complex interactions. The climatic significance is presented through large-scale anti-correlations between aerosol and precipitation anomalies, showing spatial and seasonal variability, but their precise cause-and-effect relationships remain an open-ended question. To facilitate an improved understanding of the regional aerosol radiative effects, which continue to be one of the largest uncertainties in climate forcing, a joint international effort is required and anticipated to commence in springtime 2013 in northern Southeast Asia.

biomass burning aerosols↗