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Experimental installation for measurements of effect of cosmic radiation east-west asymmetry
Natural remanent magnetization direction in West Virginia Lower Permian Dunkard series compared with other Permian data
East-west asymmetry in solar wind velocity
East-west asymmetry in solar wind velocity due to solar rotation effects on interaction between fast and slow streams
Geologic interpretation of Gemini 5 photograph of Salt Range-Potwar Plateau region, West Pakistan
Trapped protons east-west asymmetry observations during Gemini 4 flight, using on-board high sensitivity plastic-scintillation spectrometer
Excellent space photography of parts of the southwestern United States and northwestern Mexico was obtained during the unmanned Apollo 6 spaceflight. Two features of this photography made it useful for geologic interpretations: its vertical stereocoverage and its exposure under a relatively low angle of solar illumination through an unusually cloud-free and clear atmosphere. The structural patterns, which were topographically enhanced by the longer shadows, were annotated on the photographs, in order to analyze their trends with respect to the continental tectonic framework, and to attempt to correlate the pattern with known copper or other base metal deposits. The annotated fracture patterns showed the regional trends and their distribution. The area studied was a 100- to 105-mile swath of terrain covering a total land area of approximately 60,000 square statute miles. The coverage began from a point centered on Punta Colnett on the Pacific coast of Baja California and extended to the Sacramento Mountains of New Mexico and west Texas.
The West German tracking stations are equipped with ballistic cameras. Plate measurement and plate reduction must therefore follow photogrammetric methods. Approximately 100 star positions and 200 satellite positions are measured on each plate. The mathematical model for spatial rotation of the bundle of rays is extended by including terms for distortion and internal orientation of the camera as well as by providing terms for refraction which are computed for the measured coordinates of the star positions on the plate. From the measuring accuracy of the plate coordinates it follows that the timing accuracy for the exposures has to be about one millisecond, in order to obtain a homogeneous system.
Quartz crystals from calcite veins of unknown age in Precambrian metasedimentary rocks at Geiaus No. 6 and Aukam farms in South-West Africa contain both primary and secondary inclusions filled with one substance or a combination of substances. These substances include organic liquid, moderately saline aqueous liquid, dark-colored solid, and a vapor. Analysis of these materials by microscopy and by gas chromatography and mass spectrometry shows the presence of constituents of both low and high molecular weights.
Asymmetry of sunspot area with respect to the central meridian is found to depend strongly on the location of the spot group in its chromospheric facula or plage. The usual area excess for spots in the eastern half of the disk is reversed for the relatively rare spot groups situated in the following part of the plage. Qualitatively, the observed asymmetries can be explained by supposing that the apparent area of the spot is decreased by overlying bright facula, especially west of central meridian where the spot (in the usual preceding position) is viewed through the relatively bright and extensive follower part of the plage. Since both facula and spot effects are seen along the same line of sight, optical depth must change slowly with geometric depth, that is, in the active region the atmosphere is relatively transparent.
Theoretical analysis and experimental data are combined to yield the errors to be used with antenna gain, antenna patterns, and RF cable insertion loss measurements for the Mariner Venus-Mercury 1973 Flight Project. These errors apply to measurements conducted at the JPL Mesa, West Antenna Range, on the high gain antenna, low gain antenna, and RF coaxial cables.
A technique has been developed to measure the electromagnetic east-west drift velocity of the F region ionosphere by means of the Jicamarca incoherent scatter radar. Results show a fairly consistent behavior from day to day even during a magnetically disturbed day. Velocities are westward with a maximum of the order of 50 m/sec during the day, and eastward with a maximum of the order of 135 m/sec during the night. They are shown as experimental evidence for the superrotation of the neutral atmosphere at equatorial latitudes, but with a velocity smaller than the values inferred from satellite drag.
There are substantial needs of the Sahelien Zone to detail the state of regional agricultural resources in the face of a sixth year of serious drought conditions. While most of the work has been done in the Republic of Niger, the principles which have emerged from the analysis seem to be applicable to much of the Sahel. The discussion relates to quite specific rehabilitation and development initiations under consideration in Niger which are based in part upon direct analysis of ERTS imagery of the country, in part on field surveys and on discussions with Nigerian officials and technicians. Again, because the entire Sahelien Zone (including Niger) has large zones of similar ecologic characteristics, modificiations of the approaches suggested for Niger are applicable to the solution of rehabilitation of the desert, the savannah and the woodlands of West Africa in general.
The largest contour strip mining operations in western Maryland and West Virginia are located within the Georges Creek and the Upper Potomac Basins. These two coal basins lie within the Georges Creek (Wellersburg) syncline. The disturbed strip mine areas were delineated with the surrounding geological and vegetation features using ERTS-1 data in both analog (imagery) and digital form. The two digital systems used were: (1) the ERTS-Analysis system, a point-by-point digital analysis of spectral signatures based on known spectral values, and (2) the LARS Automatic Data Processing System. The digital techniques being developed will later be incorporated into a data base for land use planning. These two systems aided in efforts to determine the extent and state of strip mining in this region. Aircraft data, ground verification information, and geological field studies also aided in the application of ERTS-1 imagery to perform an integrated analysis that assessed the adverse effects of strip mining. The results indicated that ERTS can both monitor and map the extent of strip mining to determine immediately the acreage affected and indicate where future reclamation and revegetation may be necessary.
Rocket-ultraviolet spectra of comet West 1975n are reported which were obtained with scanning spectrophotometers in the wavelength range from 1200 to 1300 A. The principal emission features observed include lines of C, O, and C(+), as well as bands of OH, CO, CO(+). The estimated fluxes of the C, O, H, CO, and OH features are found to be consistent with a photodissociation source in which the CO evaporation rate is about one-third that of water. The presence of a large number of carbon atoms in the metastable 1D state is indicated and taken to suggest that dissociative recombination is important near the cometary nucleus, that CO must originate in the nucleus, and that CO is the primary carbon constituent of the comet.
Observations of Comet West (1975n) at wavelengths from 0.5 to 18 microns and at a variety of scattering angles are used to infer the scattering phase function for the cometary dust. This function is strongly peaked in the forward direction. The form of the function indicates that the particles are dielectric grains with radii of approximately 1 micron. Abrupt increases in the intrinsic brightness of the coma (both in scattered sunlight and in thermal emission) are consistent with the projected times of comet fragmentation.
The spectrum of comet West (1975 n) was recorded on March 7 and 11, 1976, in the wavelength interval from 5700 to 8200 A at an intermediate resolution. One hundred twenty-two emission lines are reported, with 78 lines having identifications with spectral features of NH2, H2O(+), C2, O I forbidden emission, and Na I.
Observations made when earth crossed the orbital plane of comet West in 1976, providing an 'edge-on' view of the multiple nucleus, are used to calculate improved orbital elements for nucleus A at the time of crossing, for nucleus B relative to A and to D, and for nucleus D relative to A. The results appear to confirm that the motions of the fragments normal to the orbital plane were rather insignificant. Difficulties created by this finding for the solar-attraction theory on the rate of separation of split-comet fragments are discussed. The motion of a comet fragment off the orbital plane of the principal nucleus is analyzed in terms of both the initial-impulse and the nongravitational-acceleration hypotheses. Prospects for observing the nuclei of this comet at the next favorable edge-on projection (July 21, 1977) are evaluated.