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An east-west line designated under the Land Ordinance of 1785 to facilitate the surveying and numbering of townships in the United States.
Geographic Information System (GIS)
A computer system that stores, organizes, analyzes, and displays geographic data.
Global Positioning System (GPS)
A system that determines the precise position of something on Earth through a series of satellites, tracking stations, and receivers.
International Date Line
180 Longitude, crossing East moves back a day, crossing West moves forward one day
A circle drawn around the globe parallel to the equator and at right angles to the meridians.
The meridian, designated at 0° longitude, which passes through the Royal Observatory at Greenwich, England.
The acquisition of data about Earth's surface from a satellite orbiting the planet or other long-distance methods.
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