A CIESE Collaborative Project

Welcome to the Noon Day Project

The Noon Day project is open!!!


Measuring the Circumference of the Earth

The Goal of the Noon Day Project is to have students measure the circumference of the earth using a method that was first used by Eratosthenes over 2000 years ago.

Students at various sites around the world will measure shadows cast by a meter stick and compare their results.

From this data students will be able to calculate the circumference of the earth.

The Eratosthenes Experiment

Watch as Carl Sagan describes some of the background surrounding Eratosthenes' experiment, which is the basis for this project.