Here's your chance to repeat the creative and imaginative experiment performed by ancient cosmologist Eratosthenes over 2000 years ago! Armed with a vertical pole, a measuring tape or meter stick, and the noonday sun, you too can measure the circumference of the Earth; simple, elegant and surprisingly accurate!

Record the length of the pole, the length of the shadow at precisely solar noon (the time when the sun is at its highest point in the sky), and your latitude. Submit your data and we will provide measurements from a second location for you to complete your calculations, just like Eratosthenes.

This link will provide you access to written lessons, data report sheet, teacher guide, student photos, and further instructions; https://bit.ly/EratosthenesLessons.

Want instructions for how to make a simple vertical stick stand? https://bit.ly/StickStand

Questions or need help?
Contact Dr. David Sederberg, Purdue Physics and Astronomy, [email protected]

Thanks to Jonathan Sullivan-Wood for the artistic thumbnail design.