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Earth properties
Datums
Latitude & Longitude
Geographic Coordinate Systems
Map projections
100
a reference surface or model of Earth that is used for plotting locations anywhere on the actual surface of the Earth
What is a datum?
100
This datum was developed by the National Geodetic Survey, together with Canadian agencies, and is used as the datum for much data for the Unites States and the North American continent as a whole.
What is the North American Datum of 1983 (NAD83)?
100
These three measurements are used as the measurement system in the GCS (geographic coordinate system).
What are degrees, minutes and seconds (DMS)?
100
This unit of measurement can be broken down into 60 subsections (each one referred to as a second of distance). One unit of this measurement in latitude is roughly equal to one nautical mile (1.15 miles).
What is a minute?
100
This map projection was developed in 1569 by a Flemish cartography for use as an aid in navigation because every straight line on a map in this projection was a line of constant direction; however, it greatly distorts the sizes of land masses.
What is the Mercator projection?
200
A model of the rounded shape of the Earth that is larger at its center than at its poles
What is an ellipsoid?
200
This datum was developed by the US Department of Defense and is used by the Global Positioning System (GPS) for locating points worldwide on Earth's surface.
What is the World Geodetic System of 1984 (WGS84)?
200
This line of longitude runs through Greenwich, England and serves as the 0 degree line of longitude to base measurements east and west from.
What is the Prime Meridian?
200
When making measurements on a sphere, this distance is the shortest distance between two points on a spherical surface.
What is the great circle distance?
200
This type of map projection has a developable surface that is like a tube of paper wrapped around the Earth.
What is a cylindrical projection?
300
A model of the Earth that uses mean sea level as a base for the surface of the Earth.
What is a geoid?
300
This computational process is required to alter the measurements from one datum to another.
What is a datum transformation?
300
These imaginary lines on the globe are parallel and north or south of the equator and serve as a basis of measurement in the geographic coordinate system (GCS)
What are parallels of latitude?
300
This system divides the world into 24 subdivisions of 15 degrees of longitude and relates the time in each subdivision to the time in Greenwich, England.
What are time zones?
300
This type of map projection has only one point of tangency between the developable surface and the surface of the earth.
What is an azimuthal projection?
400
The science of measuring Earth's shape.
What is geodesy?
400
A global reference system that consists of a set of global latitude and longitude measurements used for determining the exact position of a point on Earth.
What is the geographic coordinate system (GCS)?
400
The abbreviation GCS stands for this.
What is the geographic coordinate system?
400
The imaginary line on the globe uses the 180th meridian as it basis (roughly) andmarks the division between 24-hour periods and divides one day from another.
What is the International Date Line?
400
This grid system works by dividing the Earth into a series of 60 zones that each 6 degrees of longitude wide and only covers the Earth from between 84 degrees north latitude and 80 degrees south latitude.
What is the Universal Transverse Mercator (UTM) grid system?
500
This datum was developed for measurements of the United States and North America. It has its center point positioned at Meades Ranch in Kansas.
What is the North American Datum of 1927 (NAD27)?
500
This imaginary line runs around the center of the Earth and serves as the 0 degree line or the starting point that lines of latitude are made from. Measurements north of this line read as north latitude and measurements south of this line read as south latitude.
What is the Equator?
500
This unit of measurement can be broken down in to 60 subsections (each one referred to as a minutes of distance).
What is a degree?
500
The translation of coordinates and locations on the three-dimensional (3D) Earth to a two-dimensional surface (map). There is always distortion in this process.
What is map projection?
500
This grid-based system, designed in the 1930s, is a projected coordinate system for the United States, creates zones using state or county boundaries (California has six zones), and baselines and principal meridians.
What is the State Plane Coordinate System (SPCS)?