Glossary M through O
Mean Earth-Sun distance is the arithmetical mean of the maximum and minimum distances between a planet (Earth) and the object about which it revolves (Sun).
Mercator is a conformal map projection, that is, it preserves angular relationships. Mercator was designed and is recommended for navigational use and is the standard for marine charts. Mercator is often and inappropriately used as a world map projection in atlases and for wall charts where it presents a misleading view of the world because of the excessive distortion of area in the higher latitude areas.
A unit of length equal to one-millionth of a meter. It also is referred to as a micron.
Micronesia is comprised of Pacific island groupings located at 9.30 degrees north latitude and 143.00 degrees east longitude with a total land area of approximately 700 square kilometers. The Federated States of Micronesia include Kosrae, Pohnpei, Truk, and Yap.
The subset of the Electromagnetic Spectrum encompassing wavelengths between .03 and 30 centimeters, corresponding to frequencies of 1-100 gigahertz.
Unit of angular measure equal to one-thousandth the angle subtended at the center of a circle by an area of length equal to the radius of the circle.
The MMSP is a frame synchronizer designed to provide the interface between bit synchronized Landsat thematic mapper telemetry data and the host computer system. It is used as the front end for a Landsat data acquisition system that accepts raw serial telemetry data from high density tape (HDT), frame aligns, samples user specified fields, and presents these data to the host computer for decommutation and image extraction.
That value that occurs most frequently within the data sample being taken. In a histogram, it is the data value at which the peak of the distribution curve occurs.
The process by which some characteristics of one carrier wave are varied in relation to another wave or signal.
The MOSS is a vector based GIS system that was first implemented in 1977 by the U.S. Bureau of Land Management.
The MSS is a nonphotographic imaging system which utilizes an oscillating mirror and fiber optic sensor array. The mirror sweeps from side to side, transmitting incoming energy to a detector array which sequentially outputs brightness values (signal strengths) for successive pixels, one swath at a time. The forward motion of the sensor platform carries the instrument to a position along its path where an adjacent swath can be imaged. The MSS simultaneously senses radiation using an array of six detectors in each of four spectral bands from 0.5 to 1.1 micrometers.
The use of one or more sensors to obtain imagery from different portions of the electromagnetic spectrum.
NAD27 is defined with an initial point at Meads Ranch, Kansas, and by the parameters of the Clarke 1866 ellipsoid. The location of features on USGS topographic maps, including the definition of 7.5-minute quadrangle corners, are referenced to the NAD27.
NAD83 is an Earth-centered datum and uses the Geodetic Reference System 1980 (GRS 80) ellipsoid, unlike NAD27, which is based on an initial point (Meades Ranch, Kansas). Using recent measurements with modern geodetic, gravimetric, astrodynamic, and astronomic instruments, the GRS 80 ellipsoid has been defined as a best fit to the worldwide geoid. Because the NAD83 surface deviates from the NAD27 surface, the position of a point based on the two reference datums will be different.
Point on the ground vertically beneath the center of a remote sensing platform.
NAPP was established to coordinate the collection of aerial photography covering the 48 contiguous States and Hawaii every five years. NAPP's goals are to ensure that photography with uniform scale, quality, and cloud-free coverage be made available to meet the requirements of several Federal and State agencies. The program was initiated in 1980 as the National High Altitude Photography (NHAP) program. In 1987, the program was renamed to NAPP when the flying height for the program changed from 40,000 feet to 20,000 feet. NAPP photography is available in black and white, and in most cases, color-infrared. The program is administered by the U.S. Geological Survey's National Mapping Division. NAPP imagery is used by the USGS for photo revision and land use land cover characterization work on the standard series maps at 1:24,000; 1:100,000 and 1:250,000 scales.
The NASA was formed during the administration of President Dwight D. Eisenhower as a response by the President and the United States Congress to achievements in space by the then Union of Soviet Socialist Republics (USSR) including Sputnik I and II. Emphasis was placed on consolidating projects, facilities, and personnel into a national program including the National Advisory Committee for Aeronautics (NACA) which would later become the nucleus for the NASA. The NASA researches solutions to flight problems within and outside of the Earth's atmosphere. The NASA also develops, constructs, tests, and operates aeronautical and space vehicles. These vehicles, both manned and unmanned, are part of the NASA's research activities in the exploration of space. In addition, the NASA coordinates the scientific and engineering resources of the United States with other nations engaged in aeronautical and space activities for peaceful purposes.
The ARC's two installations are located at Moffett Field, California, and at the Dryden Flight Research Facility in Edwards, California. The ARC is responsible for managing a diverse series of research and technology development programs in support of NASA activities including flight simulation and research; aerospace and human factors; atmospheric and Earth sciences applications; and space biology and medicine. The ARC also is responsible for maintaining research and test facilities and equipment including wind tunnels, simulators, supercomputers, and aircraft.
NASA/JSC or JSC supports the acquisition of Earth observations photography by training the astronauts in Earth science and providing real-time mission support to make the crew aware of photo opportunities during the flight (i.e, hurricanes, fires, floods, volcanoes, ice flows, etc.). JSC also trains the crew to use the camera systems and the techniques needed to acquire high quality photography of Earth and environmental phenomena. After each mission JSC catalogs the acquired photography and enters new records into the Space Shuttle Earth Observation Program (SSEOP) data base. This data base is accessible from GLIS through the use of the REMOTE MENU option.
The National Atlas of the United States of America is a bound collection of full-color maps and charts showing physical features such as landforms, geology, soil, vegetation, and climate. It is produced by the U.S. Geological Survey's Topographic Division in cooperation with other Federal agencies and private organizations. Economic, social, and cultural information is also presented. All maps of the United States contained in the National Atlas are based on the Albers equal area projection.
Reference surface established by the U.S. Coast and Geodetic Survey in 1929 as the datum to which relief features and elevation data are referenced in the conterminous United States; formerly called "mean sea level 1929."
Specifications promulgated by the U.S. Office of Management and Budget to govern accuracy of topographic and other maps produced by Federal agencies.
The NATSGO data base is used primarily for national and regional resource appraisal, planning, and monitoring. The boundaries of the Major Land Resource Areas (MLRA) and regions were used to form the NATSGO data base.
This is a technique of examining the total gamma radiation of rocks in a drill hole.
The NCAR, based out of Boulder, Colorado, performs research related to atmospheric problems. NCAR provides service to the university research community and conducts research toward achieving a better understanding of the overall behavior of the atmosphere, including analyzing and predicting atmospheric behavior, establishing solar terrestrial connections, understanding air chemistry and climate, evaluating environmental and societal effects, and studying connective storms and severe weather.
The NCDS is an interactive scientific information management system that allows researchers to locate, access, manipulate, and display a wide variety of climate data. This data can be analyzed on the NCDS host computer or downloaded to other computers for additional analysis. The NCDS library includes many data sets from NASA satellites and various conventional data base sources. This system is located at the Goddard Space Flight Center in Greenbelt, Maryland.
The NCSS is a joint effort of the United States Department of Agriculture and agencies of the States, usually the Agriculture Experiment Stations. In some surveys, other Federal and local agencies also contribute. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the NCSS.
The NDCDB is a collection of the digital cartographic/geographic data files produced by the U.S. Geological Survey (USGS) as part of the National Mapping Division (NMD). The NDCDB contains elevation data, planemetric data, and landuse and landcover data in various map scales. The digital data are useful for the production of cartographic products such as plotting base maps and for various kinds of spatial analysis. A major use of these digital cartographic/geographic data is to combine them with other geographically referenced data, enabling scientists to conduct automated analyses in support of various decision making processes.
The NDVI is computed by calculating the ratio of the VI (vegetation index, i.e., the difference between Channel 2 and 1) and the sum of Channels 2 and 1. Thus NDVI = (channel 2 - channel 1) / (channel 2 + channel 1).
Neatlines separate the body of a map from the map margin. On quadrangle maps, the neatlines are often the meridians and parallels that delimit the quadrangle.
NESDIS is the element in NOAA that is responsible for establishing a digital archive of data collected from the current generation of NOAA operational polar orbiting satellites.
The NGDC at Boulder, Colorado, was created in 1965. It is one of three data and information centers of NOAA's National Environmental Satellite, Data and Information Service (NESDIS). NGDC brings together in one data center activities in solar-terrestrial physics, marine geology/geophysics, and solid earth geophysics.
Activities formerly part of Combat Support Center (see DMA).
The Nimbus satellite program, initiated by the National Aeronautics and Space Administration (NASA) and later operated by both NASA and the National and Oceanic Atmospheric Administration (NOAA), was developed in the early 1960s to meet research and development needs of the atmospheric and Earth scientists, providing global surveillance of the atmospheric structure at low Earth orbital altitudes for the world's weather services.
When correcting image data points, the nearest neighbor technique assigns for each new pixel that pixel value which is closest in relative location to the newly computed pixel location.
The NOAA, under the Department of Commerce, operates the civil polar-orbiting and geo-stationary satellite systems for the collection of atmospheric and environmental data.
In 1916, Congress enacted the establishment of the NPS to provide unified administration of parks and monuments. The NPS manages a diverse system of entities including parks, monuments, historic sites, battlefields, seashores, lakeshores, and recreation areas. The NPS also directs programs to assist other Federal agencies, State and local governments, and individuals in the protection of architectural, archeological, historical, and natural resources that are not part of the National Park System.
The U.S. Department of Agriculture's Natural Resources Conservation Service (NRCS) provides leadership and administers programs to help people conserve, improve, and sustain natural resources and the environment. NRCS' work covers three major areas: soil and water conservation, natural resource surveys, and community resource protection and management. Prior to 1995, NRCS was known as the SCS (Soil Conservation Service).
Executive Order 12906, "Coordinating Geographic Data Acquisition and Access: The National Spatial Data Infrastructure," was signed on April 11, 1994, by President William Clinton. Under this order, each Federal agency is to document all new geospatial data it collects or produces, either directly or indirectly, using the standard developed by the Federal Geographic Data Committee (FGDC) and make that documentation electronically accessible to the Clearinghouse network.
An image taken with a camera or sensor with the axis intentionally directed between the vertical and horizontal planes. A high oblique image includes the horizon in the field of view, while a low oblique shows only the Earth's surface.
The ONC series covers most of the world landmass areas at 1:1,000,000 scale. At this scale it takes 62 charts to cover the conterminous United States. Information on these charts includes cities and landmarks, drainage, and relief (shown by shading and contours). International and State boundaries are shown, but not county boundaries.
Headquartered in Redwood Shores, California, Oracle provides relational database products, development tools, and client/server applications.
For more information, see the Oracle homepage.
ORNL, under the Department of Energy's Environmental Science Division and host to the Carbon Dioxide Information Analysis Center, is located in Oak Ridge, Tennessee. Approximately 15,000 research scientists are working on projects sponsored by the Department of Energy, Environmental Protection Agency, Federal Regulatory Commission, and other Government offices. Research activities focus on the variety of unique aspects relating to global change and energy concerns.
Correction applied to satellite imagery to account for terrain-induced distortion.
That portion of an arc (line) digitized past its intersection with another arc. See dangling arc.
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