Proviamo a misurare la distanza Terra-Sole

Photographs of the last transits of Venus across the Sun, shot by amateur astronomers in 2004 and 2012, can be used to measure the mean distance between the Earth and the Sun (AU – Astronomical Unit).
The method is simpler – although less precise – than the one proposed by the famous astronomer Edmond Halley about 300 years ago. This method allows students to perform many amusing computer and laboratory activities. If the work is done carefully a measure of the AU in good agreement with the accepted value can be obtained.