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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.

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.

satellite data is also needed.

Longer term research and development in the use of Earth resource 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, The objective of the hearings is ". Administration planning and the range of opportunities which exist for future space programs."

1978.

to review current

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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EARTH RESOURCES OBSERVATION SYSTEMS PROGRAM

To facilitate the use of current and future space systems, the

Interior Department established the Earth Resources Observation Systems (EROS) Program in 1966. The purpose of the EROS Program is to develop, demonstrate, and encourage applications of remotely sensed data acquired from aircraft and spacecraft which are relevant to functional responsibilities of the Department. The primary areas of activity are:

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The Interior Department seeks to take maximum advantage of space technology to fulfill its responsibilities commensurate with economy and efficiency. Research using space data and technology has led to beneficial uses within the Department and provision of space data to some organizations with similar responsibilities in State and local governments as well as foreign countries. Along with use of the technology goes the fundamentally important task of assuring that the needs of the Interior Department are known by the National Aeronautics and Space Administration (NASA) and that NASA's space research and development is aimed at meeting those needs. The EROS Program discusses with NASA the results of present space technology use, the improvements needed in present systems, Interior's identified information needs, and the design of new systems to meet those needs.

The key facility of the EROS Program is the EROS Data Center (EDC)

in Sioux Falls, South Dakota, the principal archive for remotely sensed data collected by U.S. Geological Survey (GS) aircraft, by NASA

research aircraft, and by Landsat, Skylab, Apollo, and Gemini spacecraft.

24-215 O-78-28

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