Chapter Two - Navigating Our World: Geodesy, Datums, and Coordinate Systems

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Chapter Goals

  1. Define and explain classic geodesy
  2. Define and explain modern geodesy
  3. Define and explain GNSS
  4. Define topographic surface
  5. Define geoid
  6. Explain what a geoid is a model of how the model is made
  7. Explain why geoids are used in GIS and Cartography
  8. Define ellipsoid
  9. Define spheroid (ellipsoid of revolution)
  10. Define reference ellipsoid, global reference ellipsoid, local reference ellipsoid
  11. Explain when and why we use ellipsoids
  12. Explain when and why we use spheroids
  13. Define and explain Cartesian Coordinate Systems
  14. Define geodetic datum
  15. Explain how geodetic datums are made
  16. Define benchmark and control points
  17. Explain the similarities and difference between benchmarks and control points
  18. Define and explain horizontal and vertical datums
  19. Define orthometric height
  20. Define ellipsoid height
  1. Define geoid separation
  2. Explain when we use orthometric height, ellipsoid height, and geoid separation
  3. Define and explain datum shifts, both major and minor
  4. Define Earth-centered, Earth-fixed Coordinate Systems
  5. Define and explain geographic grid
  6. Explain where a geographic grid is drawn
  7. Thoroughly explain geographic coordinate systems (GCS) including the parts it's made up of, why it's used, and how it differs from a geographic grid
  8. Define projected coordinate systems (PCS)
  9. Explain the advantages of PCS's
  10. Explain the disadvantages of PCS's 
  11. Define and explain distortion, naming the six kinds of distortion
  12. Define and explain developable surface
  13. Name the three major developable surfaces
  14. Define and explain projection aspect
  15. Name the three major projection aspects
  16. Define and explain projection method
  17. Explain the difference between a projection method and a PCS
  18. Define and explain the State Plane Coordinate System
  19. Define and explain the Universal Transverse Mercator (UTM) system
  20. Define map scale