Eratosthenes calculated the circumference of the Earth, long time ago. We 're going to do the same calculation. Take a look at these movies.

 

 

 

Therefore we need to start measuring the shadow of a 1 m stick at solar noon.

To know the exact time of solar noon, you can calculate the time HERE or HERE

Every day you did a measure, please add the result in the shared spreadsheet

After some measurements we can start calculating.

We can also use some virtual labs to inquiry about this phenomenon: click here to find your shadow, here to see how your shadow moves when the Sun moves and here to verify the Sun movement and sunlight phases during the given day at the given location.

Brest 12:00 17th March 2016:  Clement, Edouard and Paul measure the shadow

Bulgaria: Silvia, Gtoian, Daiana and Georgi - 28.03.2016 g.

Stoian and Gabriela 28.03.2016g.

After we collected the measures, we students calculated the circumference of the Earth using the same method of Eratosthenes.

Here you can see some Bulgarian students calculating the circumference of the earth.

Here you can see some French students calculating the circumference of the Earth.