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Microwave studies of natural materials
Applications using data acquired by sensors in the visible and
near infrared part of the electromagnetic spectrum (e.g., the multispectral scanner on Landsat) have been very successful, but acquisition of important data is commonly hampered by inclement weather, or obscured by vegetation. Microwave systems offer a possible alternative to obtain these data; these systems also provide data from another part of the electromagnetic
Microwave systems operate in radio wavelengths of from 1 mm to several meters. The basic systems can be divided into those which are passive and record energy emitted by the Earth, and those which are active and record the reflection of energy. The active systems can produce images (conventional radar) or information in terms of scattering coefficients. Both the passive and the active systems provide an essentially all-weather capability and both address the objective of observing conditions both at and below the surface of the Earth. spatial resolution of the systems is inversely proportional to the wavelengths, while penetration (shallow--a few centimeters or meters) of the Earth is directly proportional to wavelength. Local conditions, however, such as soil moisture, vegetative cover, and rock type have an effect on penetration.
Possible applications of data acquired by passive microwave systems aboard Earth satellites include:
a. Mapping the distribution of sea ice,
b. Mapping the distribution of oil slicks on water (Edgerton and
C. Measurement of ice thickness (Adey, 1972),
Luminescence is the property of some materials to emit light when excited by external stimuli such as ultraviolet or visible light or by chemical or mechanical action. The Fraunhofer line discriminator (FLD) is an electro-optical device, developed by the EROS Program and NASA, which permits detection of solar-stimulated luminescence several orders of magnitude below the intensity detectable with the human eye (Hemphill and others, 1969; Watson and others, 1974). Tests of the FLD, operating from a helicopter in a non-imaging radiometer mode, permitted measurement of differences in the luminescence of trees growing in soils containing geochemically anomalous concentrations of copper near Denver, Colorado, and molybdenum near Gardinerville, Nevada, from trees growing in background areas nearby (Hemphill and others, 1977). The FLD also distinguished luminescing phosphate rock and gypsum from sandstone and siltstone near Pine Mountain, California, dispersal of oil in a natural seep from seawater in the Santa Barbara Channel (Hemphill and others, 1977), cattle feed lot effluents near Denver, and paper mill and phosphate processing effluents in Florida (Watson and Hemphill, 1976).
Modifications of the FLD early in 1977 now permit operation from
fixed-wing aircraft in an imaging mode.
Luminescing materials successfully
imaged with the modified FLD include the Santa Barbara Channel oil seep and uranium-bearing sandstones in the Sandia Mountains, New Mexico (Watson and others, in press; Watson and Theisen, 1977).
Airborne use of the FLD in both radiometer and imaging modes has been demonstrated for the detection and delineation of a variety of
geologic, agricultural, and pollution materials.
STEEL THAT HAS BEEN POURED IN PITTSBURGH NOW COMES FROM JAPAN
MORE THAN 15.000 PEOPLE LOST THEIR JOBS IN THE AMERICAN SHOE INDUSTRY TO SOUTH KOREA, TAIWAN AND OTHER COUNTRIES
GRADUAL LOSS OF THE AMERICAN ENERGY BASE LEADS TO A DECLINE IN THE POWER AND SIZE OF CARS, WITH ATTENDANT LOSSES IN JOBS
• PEOPLE IN THE STEEL INDUSTRY, THE AUTOMOBILE INDUSTRY, THE GARMENT INDUSTRY, THE SHOE INDUSTRY ETC. LOST AND LOSE THEIR JOBS IN GROWING NUMBERS TO FOREIGN COMPETITION
SINCE 1970. ABROSPACE ENGINEERS AND WORKERS LOST THEIR JOBS IN DROVES, DUE TO LACK OF IMAGINATIVE REALISM IN EXPLOITING OUR NEW CAPABILITIES
• NOW THEY ARE JOINED BY ELECTRONIC ENGINEERS AS THE ELECTRONIC AND CYBERNETIC COMPETITION OF JAPAN AND W.EUROPE GAINS MOMENTUM
MORE AND MORE COUNTRIES CAN PRODUCE WHAT ONCE AMERICA PRODUCED VIRTUALLY WITHOUT COMPETITION
AS THE WORLD CONTINUES TO INDUSTRIALIZE, GLOBAL COMPETITION FOR AMERICA WILL INCREASE AND CONTINUE TO ERODE THE JOB BASE
ENVIRONMENTAL AND CONSERVATIONAL FAULT FINDING WITH ALMOST ANY ALTERNATE ENERGY SOURCE WILL CONTRIBUTE TO FURTHER EROSION OF OUR ECONOMIC BASE
TALK ABOUT "LIMITS TO GROWTH", "NO MORE TECHNOLOGY", "SMALL IS BEAUTIFUL" OR "SPACE COLONIES TOMORROW" WILL NOT HELP US
WE NEED TO OPEN UP NEW INDUSTRIAL TERRITORY AND MAKE IT WORK FOR PEOPLE RIGHT HERE ON EARTH
WE NEED TO BUILD A SPACE AMERICA. BUT WE BETTER DO NOT MAKE A MISTAKE
24-215 - 78 - 32
KEEP AWARE OF THE REALITIES
(PT 2 OF 2)
WE NEED A COMMITMENT TO A NEW INDUSTRIAL ORDER IN WHICH INDUSTRIAL
IF WE DO NOT, WE MORE THAN LIKELY WILL FACE: WORSENING DOMESTIC PROBLEMS BECAUSE OUR ECONOMIC BASE WILL CONTNUE TO SHRINK
OR WE WILL YIELD TO THE TEMPTATION TO RAISE PROTECTIVE BARRIERS AND FACE GLOBAL ECONOMIC WARFARE
IN EITHER CASE WE FACE A SHRINKING WORLD IN WHICH THE GROWING PRESSURES
THE ISSUE IS NOT TO SAVE AMERICA OR THE WORLD. THE ISSUE IS TO FORESTALL THE CRISES THAT MAY FORCE US TO HAVE TO SAVE AMERICA OR THE WORLD
LET US USE OUR NEWLY DEVELOPED SPACE TECHNOLOGIES PRODUCTIVELY IN THE
BUT LET US KEEP AN EYE ON THE REALITIES. IT'S THE IMAGINATIVE AND THE HUMAN THING TO DO
The global map reveals that the Bangui anomaly is not unique and indicates that such studies using satellite data could have significant
applications to energy and mineral studies on continental or global scales.
However, to have practical applications it is necessary to obtain measurements from satellites that are designed for such studies. Magsat, a satellite mission originally proposed by the GS to fill this need, is now scheduled for launch in September 1979. The global data acquired by the vector magnetometer in this low-altitude satellite will provide the necessary information for geological studies and also establish the dense global coverage required for improved geomagnetic references, field models, and charts.