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At least 847 records · Page 47
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

The development of hurricane Inez, 1966, as shown by satellite nighttime radiometric and daytime television coverage

A complete documentation of Numbus 2 High Resolution infrared Radiometer data and ESSA-1 and 3 television photographs is presented for the life-time of Hurricane Inez, 1966. Ten computer produced radiation charts were analyzed in order to delineate the three dimensional cloud structure during the formative, mature and dissipating stages of this tropical cyclone. Time sections were drawn throughout the storm's life cycle to relate the warm core development and upper level outflow of the storm with their respective cloud canopies, as shown by the radiation data. Aerial reconnaissance weather reports, radar photographs and conventional weather analyses were used to complement the satellite data. A computer program was utilized to accept Nimbus 2 HRIR equivalent blackbody temperatures within historical maximum and minimum sea surface temperature limits over the tropical Atlantic Ocean.

Allison, L. J.↗
NASA NTRS1973

Phenology satellite experiment

The author has identified the following significant results. The detection of a phenological event (the Brown Wave-vegetation sensescence) for specific forest and crop types using ERTS-1 imagery is described. Data handling techniques including computer analysis and photointerpretation procedures are explained. Computer analysis of multspectral scanner digital tapes in all bands was used to give the relative changes of spectral reflectance with time of forests and specified crops. These data were obtained for a number of the twenty-four sites located within four north-south corridors across the United States. Analysis of ground observation photography and ERTS-1 imagery for sites in the Appalachian Corridor and Mississippi Valley Corridor indicates that the recession of vegetation development can be detected very well. Tentative conclusions are that specific phenological events such as crop maturity or leaf fall can be mapped for specific sites and possible for different regions. Preliminary analysis based on a number of samples in mixed deciduous hardwood stands indicates that as senescence proceeds both the rate of change and differences in color among species can be detected. The results to data show the feasibility of the development and refinement of phenoclimatic models.

Dethier, B. E.↗
NASA NTRS1973

Infectivity and egg production of Nematospiroides dubius as affected by space flight and ultraviolet irradiation

Nematospiroides dubius was tested to determine the infective potential of the third stage larvae and the egg-production and egg-viability rates of the resulting adults after they are exposed to space flight and solar ultraviolet irradiation. The results are indicative that space-flown larvae exposed to solar ultraviolet irradiation were rendered noninfective in C57 mice, whereas flight control larvae that received no solar ultraviolet irradiation matured at the same rate as the ground control larvae. However, depressed egg viability was evident in the flight control larvae.

Long, R. A.↗
NASA NTRS1972

NERVA nozzle design status report

The results of the design analyses are presented along with the status of the attained design maturity of the structural elements of the nozzle jacket and various aspects of the coolant passages. The design analyses relating to the nozzle shell were based on design allowables as supported by cursory values obtained from ARMCO 22-13-5 nozzle forgings. The major aspects of the coolant passages considered include: low cycle thermal fatigue, ability to operate at 4500 R gas temperature, tube buckling, and susceptibility to erosion. The scope of the analysis is limited to processes leading to reliability assessments of failure mechanisms.

Williams, J. J.↗
NASA NTRS1973

Monitoring California's forage resource using ERTS-1 and supporting aircraft data

NASA's Earth Resource Technology Satellite (ERTS-1) launched July 23, 1972, offers for the first time the unique capabilities for regional monitoring of forage plant conditions. The repetitive coverage every 18 days, the synoptic view and the real-time recovery of the imagery for immediate analysis, combine to make the ERTS satellite a valuable tool for improving the evaluation of our rangeland resources. Studies presently underway at the University of California, Berkeley (sponsored jointly by NASA and the Bureau of Land Management), seek to determine if imagery obtained from high altitude aircraft and spacecraft (ERTS) can provide: (1) a means for monitoring the growth and development of annual and perennial range plants in California, and for determining the time and the rate of initial plant growth (germination) and terminal plant growth (maturation and senescence); (2) a means for determining or predicting the relative amount of forage that is produced; and (3) a means for mapping rangeland areas having different forage producing capabilities.

Carneggie, D. M.↗
NASA NTRS1973

Phenology satellite experiment

The detection of a phenological event (the brown wave-vegetation senescence) for specific forest and crop types using ERTS-1 imagery is described. Data handling techniques included computer analysis and photo interpretation procedures. Computer analysis of ERTS-1 multispectral scanner digital tapes in all bands was used to give the relative changes of spectral reflectance with time of forests and specified crops. These data were obtained for a number of the study's twenty-four sites located within four north-south corridors across the United States. Analysis of ground observation photography and ERTS-1 imagery for sites in the Appalachian Corridor and Mississippi Valley Corridor indicates that the recession of vegetation development can be detected very well. Tentative conclusions are that specific phenological events such as crop maturity or leaf fall can be mapped for specific sites and possibly for entire regions.

Dethier, B. E.↗
NASA NTRS1973

Application of ERTS-1 data to analysis of agricultural crops and forests in Michigan

The results reported are based on analysis of ERTS Frame 1033-15580 collected over southwestern Lower Michigan on August 25, 1972. Major agricultural crops such as corn and soybeans were approaching maturity at this data and forest canopies were dense. Extensive ground truth information was gathered by detailed field study of test strips. This detailed information was supplemented over larger areas by interpretation of RB-57 and C-47 photography and MSS imagery. Recognition processing of ERTS-1 MSS data was carried out on a digital computer. Fields and forest stands were selected as training sets and test areas. Aerial imagery was essential for locating the positions of these selected areas on ERTS digital tapes. The recognition process was successful for each type of vegetation which had a dense green canopy such as forests, corn, and soybeans. Bare soil was also recognizable as a category.

Safir, G. R.↗
NASA NTRS1973

Key technology for airbreathing hypersonic aircraft.

This paper reviews recent progress in the key hypersonic technologies, which has been good despite a relatively low priority. Successful hypersonic research engine tests have been made. Active cooling system analyses have shown potential for weight savings, alleviation of structural design problems, and long airframe life. Maturing computerized flow field theories permit optimizing engine-airframe performance. Adequate progress in the future requires an expanded technology program emphasizing hydrogen usage. A hydrogen fueled hypersonic research airplane is essential, providing critical flight data and operational experience.

Nagel, A. L.↗
NASA NTRS1972

Apollo 14 soils - Size distribution and particle types.

Particle size characteristics are discussed together with particle types, abundances, variation in the soils, questions of soil maturity, coarse fines, and ropy glasses. It is found that agglutinates are formed primarily by micrometeorite impact into lunar soil. Agglutinates appear to be the major particle type now being formed on the lunar surface. Agglutinate content of a soil increases with particle track densities and with surface exposure time.

Mckay, D. S.↗
NASA NTRS1973

Results of Apollo 16.

The results of the Apollo 16 mission are summarized, and the present level of hardware and procedures maturity is illustrated. The primary objective was to obtain a sample of the lunar highlands. It appears that the moon and its history are too complex to be explained by any of the models currently available. Contingency plans fell into three categories: (1) emergency recovery from a hazardous situation, (2) alternate plans to maximize the mission return following a hardware malfunction, and (3) alternate procedures to work around specific problems. Operational experience indicates that it is better to execute a plan with some known disadvantages than to replace it with one which has some apparent advantages but is not thoroughly understood.

Mattingly, T. K., II↗
NASA NTRS1972

Laboratory simulation of organic geochemical processes.

Discussion of laboratory simulations that are important to organic geochemistry in that they provide direct evidence relating to geochemical cycles involving carbon. Reviewed processes and experiments include reactions occurring in the geosphere, particularly, short-term diagenesis of biolipids and organochlorine pesticides in estuarine muds, as well as maturation of organic matter in ancient sediments.

Eglinton, G.↗
NASA NTRS1972

Gravity as a factor in the animal environment.

Review of current knowledge, research, and research planning on the influence of gravity upon living organisms. Discussed factors affecting the adaptability of animals to increased acceleration fields include age, sex, posture, and body size. Affected functions and aspects reviewed cover growth and mature body size, body composition, maintenance feed requirements, and feed utilization efficiency. It is expected that research involving the exposure of animals to altered gravity states will lead to new biological concepts of very broad importance.

Smith, A. H.↗
NASA NTRS1973

A model of a Martian Great dust storm.

The great Martian 1971 dust storm is described using Carrier's (1971) model of a terrestrial hurricane with a somewhat modified thermodynamic drive. The model predicts the course of development and the time elapsing in three different phases: growth, maturity, decay. All the predictions correspond reasonably well to the observed phenomena. Explanations are offered for the rarity of the storms and the time of year and location at which they most commonly commence.

Gierasch, P. J.↗
NASA NTRS1973

Fossil track and thermoluminescence studies of Luna 20 material.

Track densities in 85 feldspar crystals from L-2009 range from 2,500,000 per sq cm to greater than one billion per sq cm. This track distribution represents an intermediate case between what have been previously defined as lightly and heavily irradiated soils and suggests that the Luna 20 sample consists of a mixture of a mature, heavily irradiated component with another, lightly irradiated component. Using a two-component mixing model, the age of the lightly irradiated component is about 270,000,000 yr. It is possible, but by no means certain, that this is associated with the formation of the crater Apollonius C. At about 200 C the ratio of natural thermoluminescence to that induced by a standard irradiation is similar to that in Apollo 12 and 14 cores below about 7 cm. This confirms that most of the Luna 20 sample represents subsurface material.

Crozaz, G.↗
NASA NTRS1973

Major element compositions of Luna 20 glass particles.

Major element analyses of nineteen Luna 20 glass particles indicate that most of the Luna 20 glasses have Al2O3 contents greater than 21 wt % and compositions similar to Apollo 16 and Luna 20 rocks and soils. Three of the glass particles have low Al2O3 (less than 13 wt %) and high FeO (greater than 18 wt %) contents and were probably derived from one of the adjacent maria. The low glass content of the Luna 20 soil indicates that it is relatively young or less mature than most mare soils that have been studied.

Glass, B. P.↗
NASA NTRS1973

Meteoritic material on the moon.

Three types of meteoritic material are found on the moon: micrometeorites, ancient planetesimal debris from the 'early intense bombardment,' and debris of recent, crater-forming projectiles. Their amounts and compositions have been determined from trace element studies. The micrometeorite component is uniformly distributed over the entire lunar surface, but is seen most clearly in mare soils. It has a primitive, Cl-chondrite-like composition, and comprises 1-1.5% of mature soils. The ancient component is seen in highland breccias and soils more than 3.9 AE old. It has a fractionated composition, with volatiles depleted relative to siderophiles. The abundance pattern does not match that of any known meteorite class. The crater-forming component has remained elusive. Only a possible hint of this component has been seen, in ejecta from Dune Crater and Apollo 12 KREEP glasses of possibly Copernican origin.

Anders, E.↗
NASA NTRS1973

Extralunar materials in cone-crater soil 14141.

Radiochemical neutron activation analysis has been used to determine Ni, Zn, Ga, Ge, Cd, In, Ir, and Au in duplicate samples of lunar soil 14141 and in one additional replicate each of soils 14163 and 14259. The concentrations of extralunar trace elements Ni, Ge, Ir, and Au in 14141 and 14163 are, respectively, about 69 and 82% as high as those in 14259. Although most of the mass of 14141 appears to be ejecta from Cone Crater, a sizable contamination by mature Fra Mauro soil such as 14259 is also present. The siderophilic-element concentrations of the subregolith Fra Mauro materials are estimated to be 25 plus or minus 25% of those observed in 14259.

Wasson, J. T.↗
NASA NTRS1974

Recognition of the geologic framework of porphyry deposits on ERTS-1 imagery

The author has identified the following significant results. Three major tectonic provinces have been mapped by geologic photointerpretation of ERTS-1 imagery over the Ok Tedi test site. These areas can be characterized as follows: (1) A broad area of low relief and mature topography suggesting a history of relative tectonic stability. (2) A narrow belt of moderate to high relief, broad open folds and prominent linear features. The Mount Fubilan-type porphyry copper deposits and recent volcanic effusive centers occur in this province. (3) A heterogeneous zone of high relief and high drainage density suggestive of relative structural complexity.

Wilson, J. C.↗