Monitoring dynamic marine phenomena Landsat may be uniquely configured, both in terms of spatial resolution and in spectral sensitivity of its sensors to obtain images of dynamic marine phenomena. On June 19, 1976, an unusual Landsat band 4 image (2514-12021) was acquired off the southwest coast of Iceland, which recorded some peculiar near-surface, large-scale marine current patterns (Williams, 1977). Within the area of the image, at least eight well defined eddies are visible, and at least three well developed double eddies (one turning clockwise, the other counterclockwise) can be delineated in the near-surface waters. Individual eddies associated with the double eddies have diameters of 12 to 19 mi. The area of the image is a region of high productivity of phytoplankton and zooplankton which support a large and economically important fish population. Although the light-toned water spectrally resembles sediment-laden water, the distance from the Icelandic coast (77 mi. to the center of the image) makes it more probable that the light tone of the water is the result of concentrations of phytoplankton. The variation in light- and dark-toned water is caused by extensive mixing of coastal currents, possibly modified by upwelling. MSS band 4 Landsat images may represent an important new source of data about the dynamic marine environment of coastal shelf-slope areas. STATEMENT OF KRAFFT A. EHRICKE, PRESIDENT, SPACE GLOBAL CO., to the COMMITTEE ON SCIENCE AND TECHNOLOGY HEARING ON FUTURE SPACE PROGRAMS U. S. HOUSE OF REPRESENTATIVES JANUARY 1978 - Krafft A. Ehricke - Krafft Ehricke is a native of Berlin, Germany, where he studied with plans for a space technological career aeronautical engineering, celestial mechanics and nuclear physics. Currently he heads Space Global Co.. specializing in systems research, development and consultation, in La Jolla, Calif. For more than 35 years he has been dedicated to the development of space technology, exploration and utilization. During his technical career he held executive and specialist positions with various corporations Rockwell International, General Dynamics and Bell Aircraft; and was associated with Government Agencies -- the Army Ballistic Missile Agency, Army Research & Development Division and the V-2 missile development program of the German Army Research & Development Division. He has served in advisory positions to NASA and the Air Force. 11 For the past 20 years he has been the annual space lecturer at the USAF Air University's Command and Staff School, Maxwell Air Force Base, Alabama. He is a member of the International Academy of Astronautics; and a fellow of various professional aerospace societies in this country and abroad. He participated in the development of the first ballistic missile (V-2) as well as of the first U.S. ICBM (Atlas). He conceived and directed the initial development of the first oxygen-hydrogen upper stage (Centaur) which led to the cryogenic upper stages of the Saturn vehicles and which still today launches deep space probes into the inner and outer solar system. He has introduced new concepts in many areas, from large reusable launch vehicles and space habitats to planetary missions. Parallel to his technical career, he developed new concepts As a result of his private work in these areas during the 1960s, Krafft Ehricke originated the concept of space industrialization as an essential means toward overcoming the various limits-to-growth syndromes and forming the foundation of a new cycle of manned deep space exploration. Some of these concepts are referred to in the subsequent statement and were also presented in earlier Hearings during the 1970s. Precision measurement of intercontinental distances Geological and geophysical studies have shown that large movements of parts of the Earth's crust have taken place during geologic time. Some areas are subject to geologic hazards as a result of movements taking place at the present time. In other areas, the occurrence of mineral and energy resources is closely linked to geologic structures that have resulted from these movements. A major difficulty in understanding the rates, direction, location, and cause of crustal movements has been an inability to make precise measurements over large distances and to repeat these measurements at intervals of every few years. New capabilities for precise measurements, such as laser ranging to satellites, offer the first real hope of successfully testing certain hypotheses concerning plate tectonics and sea floor spreading. The U. S. Geological Survey (1965, p. 27) states that horizontal and vertical displacements "would have to be determined within less than one decimeter; if coordinates could be determined more precisely, movements could be detected over shorter intervals." The launch of the Laser Geodynamic Satellite (LAGEOS) in May 1976 was a major step in precision measurement of intercontinental distances with accuracies of less than 5 cm. LAGEOS is a sphere 60 cm in diameter fitted with several hundred mirrors to reflect light from lasers aimed from the Earth (Table 2). In many cases it will require a decade or more of data acquisition using these measurement techniques to establish the precise rates of crustal motions. Although research has been done with microwave systems to determine the signatures of various natural materials and conditions, much work remains. Recently, NASA requested the National Academy of Sciences to review plans for the development of spaceborne microwave systems. The Academy endorsed proceeding with the passive imaging microwave program and development of active microwave spaceborne sensors that can measure the spatial distribution of elements within a scene. The Academy urged, however, that extensive and repeated experiments be carried out with multi-frequency and multi-polarization active microwave sensors under a controlled but expanded range of conditions with adequate ground truth, to determine the repeatability of research results obtained to date (National Research Council, 1977). |