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Members of a 1922 geodetic survey expedition. Until recent advances in satellite technology, namely the creation of the Global Positioning System (GPS), geodetic surveying was a task best suited to individuals with strong constitutions and a sense of adventure.
Geodesy is the science which makes global positioning possible. Geodesy is literally the science of measuring and monitoring the size and shape of the Earth and the location of points on its surface. NOAA's National Geodetic Survey (NGS) is responsible for the development and maintenance of a national geodetic data system that is used for navigation, communication systems, and mapping and charting.
The Global Positioning Tutorial is an overview of the history, essential elements, and modern methods of geodesy.
The Roadmap to Resources complements the information in the tutorial, leading you to additional information and data resources from NOAA and other reliable resources.
Heard of geodesy? These videos from NOAA's National Geodetic Survey offer a deep dive into the science of knowing where you – and everything else is in the world!
The National Science Teaching Association (NSTA) includes this resource in its database. NSTA provides educators and students access to Web-based, educationally appropriate science content that has been formally evaluated by master teachers.
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