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the Pacific Northwest Regional Commission and the States of Idaho,

Oregon, and Washington in the uses of Landsat data in resource

management.

Other current activities of the EROS Program include experimental

use of Landsat data

for studying shallow (<40 meters) sea features in the poorly mapped areas of the U.S. Trust Territories in the western Pacific;

for evaluation of Landsat as the primary reconnaissance tool

for assessing grazing capabilities and other land use; and

for compilation of an image atlas of glaciers of the world.

A key facility of the EROS Program is the EROS Data Center (EDC) in Sioux Falls, South Dakota. A major function of EDC is training of resource specialists and land managers in the use of Landsat and other remotely sensed data. A total of approximately 650 trainees participate in some 20 courses and 30 workshops each year. An important adjunct to formal training courses is the Data Analysis Laboratory, which employs the latest computerized and optical data analysis techniques, and which has become one of the finest facilities of its kind in the world.

The EROS Data Center is also the principal archive for remotely sensed data acquired by Geological Survey and NASA aircraft and data acquired by Landsat, Skylab, Apollo, and Gemini spacecraft. Since its establishment in 1972, EDC has distributed nearly 2 million reproductions from a data base of nearly 6 million images. Dollar value of data

produced totals $8 million, more than 60 percent of which has been from Landsat.

Foreign users and industry are the principal purchasers of Landsat data, each accounting for about 30 percent of total sales. Of the

145 energy-related industries on the Forbes list, 122 have ordered data from EDC during the past two years; 53 of these show a highly repetitive ordering pattern suggesting continuing operational use of the data.

Earth resource satellites to be launched in the near future, and which are of interest to the Department of the Interior, include Landsats-C and D, Magsat, and Seasat.

Landsat-C will include a thermal

band in the multispectral scanner which is expected to markedly increase knowledge of the dynamic surface properties of the Earth and be of great significance to the geological, hydrological, oceanographic, and

meteorological sciences.

Landsat-D will include a new multispectral scanner, called the Thematic Mapper, that will provide images in more spectral bands and of higher resolution than Landsats-1, -2, and -C. Data from this new scanner will be used for experimental purposes within the Department. Several years of research will be required to modify analysis capabilities and to bring the use of Thematic Mapper data to the same level of maturity now current for Multispectral Scanner data.

The Geological Survey and NASA have cooperated in the analysis of existing satellite magnetometer data, and have produced a preliminary magnetic anomaly map of the world. One of the most striking anomalies, discovered through this research, is located in central Africa and is associated with several major mineral deposits. An improved magnetometer satellite, Magsat, is scheduled for launch in September 1979, and is expected to provide the necessary information for more detailed geological studies, and for improved field models and charts.

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Seasat, to be launched in spring 1978, will provide the first

opportunity to evaluate the usefulness of space-acquired radar sensors to ongoing resource and environmental missions of the Department, especially to monitoring of polar ice and analysis of coastal environments.

Longer term research and development in the use of Earth resource satellite data is also needed. Although some weakly visible stereoscopic coverage is provided by Landsat, the areal extent of this coverage is limited to as little as 20 percent of an individual scene at the equator. Some petroleum and mining companies, and other industrial groups, recognize a need to acquire stereoscopic coverage for all the land areas of the world. Stereoscopic coverage would facilitate the analysis of subtle

landform features, drainage, and geologic structure, especially in some areas where strata are low dipping.

Luminescence is the property of some materials to emit light when excited by external stimuli such as ultraviolet lamps or the sun. Solar stimulated luminescence of a variety of geologic, agricultural, and pollution materials has been detected with airborne equipment developed by NASA and the EROS Program. Preliminary studies show that instrumentation capable of imaging luminescence and operating from the Space Shuttle is feasible. Sensitivity would be comparable to the existing aircraft system which permits detection of luminescence intensities several orders of magnitude below that seen with the naked eye.

Although data acquired by sensors in the visible and infrared parts of the spectrum have been very successful, acquisition of data is hampered by clouds and inclement weather.

Microwave systems not only are much

less weather dependent, but would also provide data from another part

of the spectrum. The National Academy of Sciences has recommended proceeding with ground and aircraft studies that may lead to a spaceborne

imaging microwave program.

Geological and geophysical studies have shown that movements of

large parts of the Earth's crust have taken place during geologic time.

Occurrence of mineral and energy resources is closely linked to geologic structure associated with these movements. The Laser Geodynamic

Satellite (LAGEOS) was launched in May 1976. This satellite is a sphere 60 cm in diameter fitted with several hundred mirrors to reflect light from lasers aimed from the Earth. Laser ranging is expected to permit precision measurement of intercontinental distances with accuracies of less than 5 cm. In many cases, it will require a decade or more of data acquisition to establish the precise rates of crustal motions.

The Geological Survey's programs in Lunar and Planetary studies have shifted from direct scientific support of lunar landings during the Apollo era to analysis of data from missions to Mars, Mercury, Venus, Jupiter, and Saturn. This exploration is directed toward a comparison of the geologic materials, processes, and history of these planets with Earth in order to achieve insight into development of the Earth's crust and processes that affect land, mineral, and energy resources.

Purpose and scope

This paper was prepared at the request of Congressman Olin E. Teague, Chairman, Committee on Science and Technology, House of Representatives, as background to that Committee's hearings on January 24, 25, and 26, 1978. The objective of the hearings is ".

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to review current

Administration planning and the range of opportunities which exist for future space programs.

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This paper reviews some of the Department of the Interior's current activities in the use of Earth resource data collected by satellite, anticipated use of data from Earth satellite missions which have been approved but not yet flown, opportunities for longer-term research in the use of Earth resource data, and current status and near future (1980's) outlook for exploration of the planets.

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