Looking Down a Well: A Brief History of Geodesy

  • Released Thursday, February 23, 2012

Geodesy is a field of study that deals with the measurement and representation of the Earth, and it all started when a clever human named Eratosthenes discovered that you could measure the circumference of the Earth by looking down a well. Over time, the field of geodesy has expanded and evolved dramatically, and NASA uses technology like radio telescopes, ground surveys, and satellites to contribute! Learn more about geodesy in this video!


Please give credit for this item to:
NASA/Goddard Space Flight Center

Release date

This page was originally published on Thursday, February 23, 2012.
This page was last updated on Wednesday, May 3, 2023 at 1:53 PM EDT.


This visualization can be found in the following series:


This visualization originally appeared on the following tapes:
  • Looking Down A Well: A Brief History of Geodesy (ID: 2012003)
    Thursday, March 1, 2012 at 5:00AM
    Produced by - Brendan Antiochos (NASA)