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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 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1978

NASA satellite to track North Pole expedition

The proposed expedition of a lone explorer and the use of Nimbus 6 (NASA meteorological research satellite) to track his journey is reported. The journey is scheduled to start March 4, 1978, and will cover a distance of 6.000 Km (3,728 miles) from northern Canada to the North Pole and return, traveling the length of Greenland's isolated interior. The mode of transportation for the explorer will be by dog sled. Instrumentation and tracking techniques are discussed.

Source record↗
NASA NTRS1978

Assessment of needs for satellite tracking of birds and suggestions for expediting a program

Equipment development and testing, animal-instrument interphase or attachment methods, and the evaluation of various feasibility-tracking experiments with raptors are described as well as suggestions for expediting a future program. Results of animal-instrument interphases work indicate that large free-flying birds can be successfully instrumented with radio packages comparable in weight to satellite-transmitter packages. The 401 MHz frequency proved satisfactory for a combination of satellite and ground tracking of migrating birds. Tests run for nearly a year with the Nimbus 6 satellite and a miniaturized, one-watt prototype RAMS transmitter produced encouraging results in regard to location accuracy, frequency of contact with satellite and use of whip antennas. A future program is recommended with priority given to development of six operational transmitters for feasibility experiments.

Craighead, F. C., Jr.↗
NASA NTRS1988

NMC stratospheric analyses during the 1987 Antarctic expedition

Stratospheric constant pressure analyses of geopotential height and temperature, produced as part of regular operations at the National Meteorological Center (NMC), were used by several participants of the Antarctic Ozone Expedition. A brief decription is given of the NMC stratospheric analyses and the data that are used to derive them. In addition, comparisons of the analysis values at the locations of radiosonde and aircraft data are presented to provide indications for assessing the representativeness of the NMC stratospheric analyses during the 1987 Antarctic winter-spring period.

Gelman, Melvyn E.↗
NASA NTRS1990

A solar power system for an early Mars expedition

As NASA looks at missions that will expand human presence in the solar system, the power requirements for such missions need to be defined, developed and analyzed. One mission under consideration consists of a 40 day manned Mars surface expedition to perform science experiments. The mission time was centered around an aerocentric longitude (Ls) of 90 deg to lessen the probability of an occurrence of a local or planetary dust storm. The mission site was arbitrarily located at the Martian equator. The power requirements were assumed to be 40 kWe for life support and experiment power during the Martian day and 20 kWe for life support during the Martian night. A solar energy system consisting of roll-out amorphous silicon arrays and a hydrogen-oxygen regenerative fuel cell energy storage system was chosen for the study. The power available from a roll-out array, when plotted against time, approaches a cosine-like curve and depends on both array area and the amount of solar irradiance impinging on its horizontal surface. The array is sized to provide at least 20 KWe when the sun is 12.5 deg above the horizon and ramp up to 140 kWe peak power at Martian noon. In this configuration, the array is capable of supplying 40 KWe continuously to the user for the majority of the Martian day while supplying the excess energy to the electrolyzer portion of the energy storage system. A roll-out, pumped loop radiator system is used to dissipate the waste heat produced by the fuel cell. The power management and distribution system inverts the power from the individual solar array sub-modules and the fuel cell stacks and connects them to a 440 VAC single phase 20 kHz main bus. The total power system is comprised of 80 individual solar array modules with an integral bus and three energy storage modules consisting of fuel cell and electrolyzer stacks, reactant storage tanks, and a roll-out radiator. Power system mass, stowed volume, and deployed area were determined. Day/night power splits of 40/10 kWe, 40/30 kWe, and 40/40 kWe were also considered to determine the impact of a range of nighttime power requirements on the baseline system.

Mckissock, Barbara I.↗
NASA NTRS1990

The Airborne Arctic Stratospheric Expedition - Prologue

This paper presents an introduction to the initial scientific results of the Airborne Arctic Stratospheric Expedition (AASE), as well as data from other atmospheric experiments and analyses carried out during the Arctic polar winter of 1989. Mission objectives of the AASE were to study the mechanisms of ozone depletion and redistribution in the northern polar stratosphere, including the influences of Arctic meteorology, and polar stratospheric clouds formed at low temperatures. Some major aspects of the AASE are described including: logistics and operations, meteorology, polar stratospheric clouds, trace composition and chemistry, and ozone depletion. It is concluded that the Arctic-89 experiments have provided the scientific community with a wealth of new information that will contribute to a better understanding of the polar winter stratosphere and the critical problem of global ozone depletion.

Turco, Richard↗
NASA NTRS1990

Temperature and wind measurements and model atmospheres of the 1989 Airborne Arctic Stratospheric Expedition

The ER-2 Meteorological Measurement System provides accurate in situ measurements of atmospheric state variables. During the Airborne Arctic Stratospheric Expedition (AASE) the ER-2 flew over the polar region on 14 occasions in January and February, 1989. Vertical temperature profiles, during aircraft takeoff at about 60 deg N and during midflight descent and ascent at high latitudes, are presented. Latitudinal variations of the horizontal wind measurement are illustrated and discussed. Based on observation data, model atmospheres at 60 deg and 75 deg N, representative of the environment of the AASE campaign, are developed.

Chan, K. R.↗
NASA NTRS1990

Measurements of condensation nuclei in the Airborne Arctic Stratospheric Expedition - Observations of particle production in the polar vortex

The ER-2 Condensation Nucleus Counter (ER-2 CNC) was operated in the Airborne Arctic Stratospheric Expedition (AASE) in January and February 1989. The ER-2 CNC measures the mixing ratio of particles, CN, with diameters from approximately 0.02 to approximately 1 micron. The spatial distribution of CN in the Arctic polar vortex was found to resemble that measured in the Antarctic in the Spring of 1987. The vertical profile of CN in the vortex was lowered by subsidence. At altitudes above the minimum in the CN mixing ratio profile, CN mixing ratios correlated negatively with that of N2O, demonstrating new particle production. CN serve as nuclei in the formation of Polar Stratospheric Clouds (PSCs) and the concentration of CN can affect PSC properties.

Wilson, J. C.↗
NASA NTRS1990

Measurements of total reactive nitrogen during the Airborne Arctic Stratospheric Expedition

Composite distributions of measured total reactive nitrogen NO(y), from the NASA ER-2 during the Airborne Arctic Stratospheric Expedition are presented. The observed features of these distributions are discussed in terms of the controlling dynamical, chemical and microphysical processes. In the latitudinal profile from 58 deg N to within about 4 deg poleward of the polar vortex boundary, NO(y) conforms closely to predictions of NO(y) based on N2O measurements. Poleward of 5 deg of latitude within the boundary, the average NO(y) decreases sharply and is significantly lower than that predicted from N2O. This feature is consistent with loss of NO(y) through sedimentation of particles containing NO(y) in polar stratospheric clouds.

Kawa, S. R.↗
NASA NTRS1990

In situ measurements of NO(x) in the Airborne Arctic Stratospheric Expedition

In situ measurements of NO and NO2 were made simultaneously from the NASA DC-8 aircraft as part of the Airborne Arctic Stratospheric Expedition. Mixing ratios of NO(x) (NO + NO2) were typically higher in the arctic troposphere than in the stratosphere, with median values of 59 and 40 pptv, respectively. In the stratosphere, there tended to be a positive correlation between NO(x) and water vapor and negative correlations between NO(x) and ozone and between NO(x) and total reactive odd-nitrogen, NO(y). The ratio of NO(x) to NO(y), in conjunction with NO(y), appears to be an excellent tracer of tropospheric or stratospheric air at northern latitudes during winter. Tropospheric NO(x) was typically 10 to 50 percent of gas-phase NO(y), while in the stratosphere, NO(x) was typically less than 10 percent, and frequently less than 5 percent of gas-phase NO(y).

Carroll, Mary Anne↗
NASA NTRS1990

Three dimensional simulation of hydrogen chloride and hydrogen fluoride during the Airborne Arctic Stratospheric Expedition

Simulations of the evolution of stratospheric distributions of hydrogen chloride (HCl) and hydrogen fluoride (HF) have been carried out for the period of the Airborne Arctic Stratospheric Expedition (AASE) with a three-dimensional chemistry-transport model. Simulations were performed assuming only homogeneous gas phase chemistry for HF and both homogeneous gas phase and heterogeneous chemistry for HCl. Results show heterogeneous loss of HCl is needed to provide agreement with infrared column measurements. Estimates of the impact of heterogeneous loss on the global HCl distribution are obtained from the model. Reductions of HCl due to heterogeneous loss are calculated to be localized to regions of high vorticity, even after more than a month of integration.

Kaye, Jack A.↗
NASA NTRS1991

Airborne lidar measurements of ozone during the 1989 airborne Arctic stratospheric expedition

The NASA/NOAA Airborne Arctic Stratospheric Expedition (AASE) was conducted during the winter to study the conditions leading to possible ozone (O3) destruction in the wintertime Arctic stratosphere. As part of this experiment, the NASA-Langley airborne differential absorption lidar (DIAL) system was configured for operation on the NASA-Ames DS-8 aircraft to make measurements of O3 profiles from about 1 km above the aircraft to altitudes of 22 to 26 km. The airborne DIAL system remotely sensed O3 above the DC-8 by transmitting two laser beams at 10 Hz using wavelengths of 301.5 and 311 nm. Large scale distributions of O3 were obtained on 15 long range flights into the polar vortex during the AASE. Selected data samples are presented of O3 observed during these flights, general trends observed in O3 distributions, and correlations between these measurements and meteorological and chemical parameters. The O3 distribution observed on the first flight of the DC-8 into the polar vortex on Jan. 6 reflected the result of diabatic cooling of the air inside the vortex during the winter compared to the warmer air outside the vortex. On a potential temperature surface, the O3 mixing ratio generally increases when going from outside to inside the vortex.

Browell, Edward V.↗
NASA NTRS1990

Aircraft deployment, and airborne arctic stratospheric expedition

The Airborne Arctic Stratospheric Expedition had two primary objectives: to study the production and loss mechanisms of ozone in the north polar stratosphere and to study the effect on ozone distribution of the Arctic Polar Vortex and of the cold temperatures associated with the formation of Polar Stratospheric Clouds. Two specially instrumented NASA aircraft were flown over the Arctic region. Each aircraft flew to acquire data on the meteorological, chemical and cloud physical phenomena that occur in the polar stratosphere during winter. The chemical processes which occur in the polar stratosphere during winter were also observed and studied. The data acquired are being analyzed.

Condon, Estelle↗
NASA NTRS1991

Human life support during interplanetary travel and domicile. III - Mars expedition system trade study

Several alternative configurations of life-support systems (LSSs) for a Mars missions are compared analytically on a quantitative basis in terms of weight, volume, and power. A baseline technology set is utilized for the illustrations of systems including totally open loop, carbon dioxide removal only, partially closed loop, and totally closed loop. The analytical model takes advantage of a modular, top-down hierarchical breakdown of LSS subsystems into functional elements that represent individual processing technologies. The open-loop systems are not competitive in terms of weight for both long-duration orbiters and short-duration lander vehicles, and power demands are lowest with the open loop and highest with the closed loop. The closed-loop system can reduce vehicle weight by over 70,000 lbs and thereby overcome the power penalty of 1600 W; the closed-loop variety is championed as the preferred system for a Mars expedition.

Seshan, P. K.↗
NASA NTRS1991

Human life support during interplanetary travel and domicile. IV - Mars expedition technology trade study

Results of trading processing technologies in a closed-loop configuration, in terms of power and weight for the Mars Expedition Mission, are presented. The technologies were traded and compared to a baseline set for functional elements that include CO2 removal, H2O electrolysis, potable H2O cleanup, and hygiene H2O cleanup. These technologies were selected from those being considered for Space Station Freedom and represent only chemical/physical technologies. Attention is given to the technology trade calculation scheme, technology data and selection, the generic modular flow schematic, and life support system specifications.

Rohatgi, Naresh K.↗
NASA NTRS1992

Radiative effects of polar stratospheric clouds during the Airborne Antarctic Ozone Experiment and the Airborne Arctic Stratospheric Expedition

Results are presented of a study of the radiative effects of polar stratospheric clouds during the Airborne Antarctic Ozone Experiment (AAOE) and the Airborne Arctic Stratospheric Expedition (AASE) in which daily 3D Type I nitric acid trihydrate (NAT) and Type II water ice polar stratospheric clouds (PSCs) were generated in the polar regions during AAOE and the AASE aircraft missions. Mission data on particular composition and size, together with NMC-analyzed temperatures, are used. For AAOE, both Type I and Type II clouds were formed for the time period August 23 to September 17, after which only Type I clouds formed. During AASE, while Type I clouds were formed for each day between January 3 and February 10, Type II clouds formed on only two days, January 24 and 31. Mie theory and a radiative transfer model are used to compute the radiative heating rates during the mission periods, for clear and cloudy lower sky cases. Only the Type II water ice clouds have a significant radiative effect, with the Type I NATO PSCs generating a net heating or cooling of 0.1 K/d or less.

Rosenfield, Joan E.↗
NASA NTRS1992

A lunar polar expedition

Advanced exploration and development in harsh environments require mastery of basic human survival skill. Expeditions into the lethal climates of Earth's polar regions offer useful lessons for tommorrow's lunar pioneers. In Arctic and Antarctic exploration, 'wintering over' was a crucial milestone. The ability to establish a supply base and survive months of polar cold and darkness made extensive travel and exploration possible. Because of the possibility of near-constant solar illumination, the lunar polar regions, unlike Earth's may offer the most hospitable site for habitation. The World Space Foundation is examining a scenario for establishing a five-person expeditionary team on the lunar north pole for one year. This paper is a status report on a point design addressing site selection, transportation, power, and life support requirements.

Dowling, Richard↗
NASA NTRS1992

The Arctic Boundary Layer Expedition (ABLE 3A) - July-August 1988

The Arctic Boundary Layer Expedition (ABLE 3A), conducted in Arctic and sub-Arctic regions of North America and Greenland during July and August 1988, was the first comprehensive investigation of the sources, sinks, and distribution of trace gas and aerosol chemical species in a northern high-latitude region during summer months. The experimental design emphasized the role of biosphere-atmosphere interactions in determining the chemical composition of the troposphere and in processes which influence the tropospheric O3 budget. This paper reports the overall experimental design of ABLE 3A and includes a brief overview of results.

Harriss, R. C.↗
NASA NTRS1992

Meteorological overview of the Arctic Boundary Layer Expedition (ABLE 3A) flight series

A meteorological overview of the Arctic Boundary Layer Expedition (ABLE 3A) flight series is presented. Synoptic analyses of mid-tropospheric circulation patterns are combined with isentropic back trajectory calculations to describe the long-range (400-3000 km) atmospheric transport mechanisms and pathways of air masses to the Arctic and sub-Arctic regions of North America during July and August 1988. Siberia and the northern Pacific Ocean were found to be the two most likely source areas for 3-day transport to the study areas in Alaska. Transport to the Barrow region was frequently influenced by polar vortices and associated short-wave troughs over the Arctic Ocean, while the Bethel area was most often affected by lows migrating across the Bering Sea and the Gulf of Alaska, as well as ridges of high pressure which built into interior Alaska. July 1988 was warmer and dryer than normal over much of Alaska. As a result, the 1988 Alaska fire season was one of the most active of the past decade. Airborne lidar measurements verified the presence of biomass burning plumes on many flights, often trapped in thin subsidence layer temperature inversions. Several cases of stratosphere/troposphere exchange were noted, based upon potential vorticity analyses and aircraft lidar data, especially in the Barrow region and during transit flights to and from Alaska.

Shipham, Mark C.↗