DM-44 - Approximating the Earth's shape with geoids

You are currently viewing an archived version of Topic Earth's Shape, Sea Level, and the Geoid. If updates or revisions have been published you can find them at Earth's Shape, Sea Level, and the Geoid.

Learning Objectives: 
  • Explain why gravity varies over the Earth’s surface
  • Explain how geoids are modeled
  • Explain the role that the U.S. National Geodetic Survey plays in maintaining and developing geoid models
  • Explain the concept of an equipotential gravity surface (i.e., a geoid)

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