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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 415 records · Page 23

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NASA NTRS1975

Earth resources experiments and results

One of the major objectives of the Skylab Program was to investigate the feasibility of addressing the techniques of resource management through the use of remote sensors from a space platform. To accomplish these investigations, a package of broad-spectrum remote sensors was devised to investigate the extent to which surface features could be interpreted for potential use in understanding and managing the earth's resources. This paper will describe the total system capability needed to accomplish the resource management task; and, for a few specific examples, indicate how the results of EREP will contribute to the on-going development of the total resources system.

Zarcaro, J. G.↗

NASA NTRS1974

The role of horizontal transport as evaluated from the Apollo 15 and 16 orbital experiments

Despite the large amount of accumulated data there is still considerable debate about the role of various processes in the formation of the lunar surface. One of the processes frequently discussed is that of horizontal transport and how it affected surface chemistry and surface features. The orbital experiments flown on Apollo 15 and 16 enable us to consider the extent of horizontal transport. In particular, the X-ray experiment because of its low penetration depth permits us to make at least crude estimates of the extent of horizontal transport.

Adler, I.↗

NASA NTRS1975

Origin and evolution of the lunar regolith; Proceedings of the Symposium, Houston, Tex., November 13-15, 1974

The papers consider the origin and evolution of the lunar regolith utilizing data obtained during American and Soviet manned and unmanned lunar missions as well as surface and orbital observations, photography, sample collections, and experimental studies. Topics include the transport and emplacement of crater and basin deposits, development of the mare regolith, the shallow lunar structure as determined from the passive seismic experiment, horizontal transport of the regolith, the origin of the exotic component and KREEP-rich materials, the influx of interplanetary materials onto the moon, stratification in the lunar regolith, catastrophic rupture of lunar rocks, cosmic-ray exposure ages of surface features, breccia formation by sintering and crystallization, evolution of the lunar soil, and effects of maturation on the reflectance of the regolith. Individual items are announced in this issue.

Source record↗

NASA NTRS1975

Satellite altimetry applied to marine geoid determination

The pioneering satellite radar altimeter aboard Skylab has provided a wealth of information about ocean surface topography for both the oceanographic and geodetic communities. This report describes typical satellite altimetry concepts and discusses the parameters measured, geometry utilized, and techniques employed to generate ocean geoid estimates. The standard deviation of the noise on the altitude measurements is shown to range from one to three meters when the altimeter antenna is nadir aligned. The altimeter is shown to sense short wavelength ocean surface features which are not included in present conventional global geoids. An estimate of a local geoid in the Atlantic, using only altimeter data, is presented. Finally, results demonstrate that the Skylab radar altimeter system capability is less than 10 meters RMS.

Leitao, C. D.↗

NASA NTRS1975

The effect of atmospheric haze on images of the earth's surface

The adding method to solve the equation of radiative transfer has been applied to a sunlit haze above a reflecting surface. The method was modified to include the effect of inhomogeneities on the underlying surface whose dimensions are less than the mean free path of the photons in the haze. Numerical examples of surface-feature contrast degradation due to haze are presented. This analysis renders it feasible to determine the optical thickness of hazes from haze-degraded images of the ground and also provides a technique to restore ground-image contrast, which has been obscured by haze, in photoelectrically scanned images.

Odell, A. P.↗

NASA NTRS1975

Lunar topography and the limb compression source regions

Data from the Apollo 15, 16, and 17 laser altimeters have been used to study slopes, elevations, and roughness in the identifiable regions on the moon which sporadically produce plasma compressions and magnetic-field enhancements in the solar wind/lunar void boundary when those regions are at a flow limb. It is found that occurrence rates for such 'limb compressions' derived from Explorer 35 satellite measurements are significantly correlated with peak, average, and RMS slopes in the source regions, whereas rates derived from Apollo 15 and 16 subsatellite data are not correlated with topography. This suggests that two or more mechanisms operate in the source regions to produce limb compressions. Together with the known correlation between limb compressions and local surface remanent magnetic fields, the results indicate that lunar magnetization is not strongly related to surface features.

Srnka, L. J.↗

NASA NTRS1976

A comparison of the Great Red Spot with temporary spots on Jupiter

The International Planetary Patrol collection of Jupiter photographs is used to examine the development of a temporary spot that was visible in the northern equatorial zone for a total of 211 days. The motion and color of this spot are compared with those of the Great Red Spot. It is shown that the temporary spot was bluer than the Great Red Spot and has a longitudinal oscillation of approximately 4 deg with a period of about 45 days, implying that it may have possessed a significant dynamical property in common with other temporary spots and the Great Red Spot. It is concluded that the present spot is more likely to have been associated with a hole in the cloud deck rather than with an elevated surface feature.

Browne, G. C.↗

NASA NTRS1976

Ice reconnaissance by satellite

The paper describes the significant milestones in the use of satellites for snow and ice monitoring. The feasibility of such monitoring was demonstrated by the Tiros 2 satellite in 1961. Nimbus 1 showed that breaks in the sea ice can be easily monitored during continuous nighttime conditions; Nimbus 3 showed the practicality of delineating regions of active melting of ice and snow in temperate areas. Landsat data have been found to be particularly useful for monitoring and studying glaciers and their attendant surface features. Ice concentration can be determined with reasonable accuracy from a sequence of electronically scanned microwave radiomenter images made aboard Nimbus 5. In the future we can expect improved sensors and spacecraft systems with longer operating lives.

Gloersen, P.↗

NASA NTRS1976

Lunar radargrammetry with ALSE-VHF imagery

Results are presented for a controlled experiment with a pair of overlapping lunar ALSE-VHF images produced in two consecutive revolutions of the Apollo command module around the moon. A theoretical treatment is presented of the mathematical tools for ALSE radargrammetry. Evaluation of radargrammetric mapping with single strips and a radar stereo model led to preliminary results in a test area around Mons Maraldi. Accuracy achieved with single radar images was about plus or minus 250 m along track and plus or minus 500 m across track. Stereoradargrammetry was used to generate a contour plot of Mons Maraldi and to evaluate the overall height accuracy obtainable from ALSE radar. About plus or minus 120 m of accuracy is obtained if the stereo model is corrected using a few control points. This makes ALSE stereo radar heights competitive with or even superior to vidicon data obtained for planetary exploration. The present basic limitation to radargrammetric accuracy from ALSE-VHF images is the identifiability of surface features.

Leberl, F.↗

NASA NTRS1974

Geologic guide to the island of Hawaii: A field guide for comparative planetary geology

With geological data available for all inner planets except Venus, we are entering an era of true comparative planetary geology, when knowledge of the differences and similarities for classes of structures (e.g., shield volcanoes) will lead to a better understanding of general geological processes, regardless of planet. Thus, it is imperative that planetologists, particularly those involved in geological mapping and surface feature analysis for terrestrial planets, be familiar with volcanic terrain in terms of its origin, structure, and morphology. One means of gaining this experience is through field trips in volcanic terrains - hence, the Planetology Conference in Hawaii. In addition, discussions with volcanologists at the conference provide an important basis for establishing communications between the two fields that will facilitate comparative studies as more data become available.

Greeley, R.↗

NASA NTRS1976

A preliminary experiment definition for video landmark acquisition and tracking

Six scientific objectives/experiments were derived which consisted of agriculture/forestry/range resources, land use, geology/mineral resources, water resources, marine resources and environmental surveys. Computer calculations were then made of the spectral radiance signature of each of 25 candidate targets as seen by a satellite sensor system. An imaging system capable of recognizing, acquiring and tracking specific generic type surface features was defined. A preliminary experiment definition and design of a video Landmark Acquisition and Tracking system is given. This device will search a 10-mile swath while orbiting the earth, looking for land/water interfaces such as coastlines and rivers.

Schappell, R. T.↗

NASA NTRS1976

Procedure for detection and measurement of interfaces in remotely acquired data using a digital computer

A technique for the detection and measurement of surface feature interfaces in remotely acquired data was developed and evaluated. A computer implementation of this technique was effected to automatically process classified data derived from various sources such as the LANDSAT multispectral scanner and other scanning sensors. The basic elements of the operational theory of the technique are described, followed by the details of the procedure. An example of an application of the technique to the analysis of tidal shoreline length is given with a breakdown of manpower requirements.

Faller, K. H.↗

NASA NTRS1977

A fundamental approach to adhesion: Synthesis, surface analysis, thermodynamics and mechanics

The effects of composites as adherends was studied. Several other variables were studied by fractography: aluminum powder adhesive filler, fiber glass cloth scrim or adhesive carrier, new adhesives PPQ-413 and LARC-13, and strength-test temperature. When the new results were juxtaposed with previous work, it appeared that complex interactions between adhesive, adherend, bonding, and testing conditions govern the observed strength and fracture-surface features. The design parameters likely to have a significant effect upon strength-test results are listed.

Dwight, D. W.↗

NASA NTRS1977

A procedure for detection and measurement of interfaces in remotely acquired data using a digital computer

A technique developed and evaluated for the detection and measurement of surface feature interfaces in remotely acquired data is described. A computer implementation of this technique has been effected to automatically process categorized data derived from various sources such as the LANDSAT multispectral scanner and other scanner type sensors. The basic elements of the operational theory of the technique are described together with details of the procedure. An example application of the technique to the analysis of tidal shoreline length is given with a breakdown of manpower requirements.

Faller, K. H.↗

NASA NTRS1976

Landsat Signature Development Program

The Landsat Signature Development Program, LSDP, is designed to produce an unsupervised classification of a scene from a Landsat tape. This classification is based on the clustering tendencies of the multispectral scanner data processed from the scene. The program will generate a character map that, by identifying each of the general classes of surface features extracted from the scene data with a specific line printer symbol, indicates the approximate locations and distributions of these general classes within the scene. Also provided with the character map are a number of tables each of which describes either some aspect of the spectral properties of the resultant classes, some inter-class relationship, the incidence of picture elements assigned to the various classes in the character map classification of the scene, or some significant intermediate stage in the development of the final classes.

Hall, R. N.↗

NASA NTRS1976

Effects of the atmosphere on remote sensing

The interaction between electromagnetic radiation and the earth's atmosphere is considered, taking into account windows in the electromagnetic spectrum, solar and terrestrial radiation, physical properties of the atmosphere, and clouds. The characteristics of upwelling radiation in the visible wavelengths are discussed along with infrared radiation and microwaves. Attention is given to radiant emittance, radiance, contrast, effects of atmospheric turbulence, ocean color, and questions concerning the classification of surface features with the aid of computers.

Fraser, R. S.↗

NASA NTRS1976

Modes of emplacement of basalt terrains and an analysis of mare volcanism in the Orientale Basin

Three distinctive types of basalt terrains can be recognized on earth on the basis of surface morphology: flood basalts, shield basalts, and plains basalts, each of which reflects unique styles of eruption and modes of emplacement. Two of these, flood basalts and plains basalts, appear to be important in the emplacement of mare basalts on the moon. Using surface features as identifying criteria, mare units in the Orientale Basin were examined and the following emplacement sequence was derived: (1) initial emplacement of impact melt in the basin center, (2) eruption of flood-type basalts in the basin center and approximately concurrent emplacement of plains type basalts in Lacus Veris, and (3) emplacement of plains type basalts in Lacus Autumni

Greeley, R.↗

NASA NTRS1978

Apollo 14 rock samples

Petrographic descriptions of all Apollo 14 samples larger than 1 cm in any dimension are presented. The sample description format consists of: (1) an introductory section which includes information on lunar sample location, orientation, and return containers, (2) a section on physical characteristics, which contains the sample mass, dimensions, and a brief description; (3) surface features, including zap pits, cavities, and fractures as seen in binocular view; (4) petrographic description, consisting of a binocular description and, if possible, a thin section description; and (5) a discussion of literature relevant to sample petrology is included for samples which have previously been examined by the scientific community.

Carlson, I. C.↗