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Solstice science activity in the works for June 19, 2021

Published Thursday April 1, 2021

Participants will be invited to use Sun's shadows on the Summer Solstice in 2021 to infer the radius of Earth.

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Spanning The Globe! Come join us for a measurement / revalidation of the Earths' circumference on June 19th, 2021.

Using only tools available to the ancient Greeks, we propose to calculate the circumference of the planet. We hope to get accuracy a little better than Eratosthenes did circa 200 BCE. We may have a slightly better gnomon but we promise not to use GPS.

Watch this space for more info.

Preparatory reading

Wikipedia article on Eratosthenes