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2016 Pi Measurement Challenge

STEAM Collaborators: 

Niles Johnson, Ph.D- Assistant Professor

College of Arts and Sciences- Mathematics


The Pi Measurement Challenge is collaborative outreach event organized by Niles Johnson and Richard Shiels, historian and director of the Newark Earthworks Center.  The challenge invited participants of all ages to help with the measurement and learn more about the history and mathematics of the Great Circle to measure its circumference, measure its diameter, and divide.

The perimeter of the Great Circle is the same as the perimeter of the Wright Earthworks Square about a mile away.  And the area of the Wright Earthworks Square is the same as the area of the Observatory Circle at- tached to the Octagon Earthworks, even further away. The American Indi- ans who built these earthworks 2000 years ago must have known the rela- tionship between circle diameter, perimeter, and area — the number that we now call π.  Four teams participated, two for circumference and two for radius. 


After averaging the teams’ measurements, here are the results:

  • Circumference: 3372.5 ft
  • Diameter: 10171.5 ft
  • π Measurement: 3.1474
  • Percent Error: 00.19%