Curved shadow of Earth
Fig. 1.5 . This multiple-exposure photograph of a total lunar eclipse reveals the curved shape of the Earth’s shadow, regarded by ancient Greek astronomers as evidence that the Earth is a sphere. Only a spherical body will cast the same circular shadow on the Moon when viewed from different locations on Earth or during different lunar eclipses. Akira Fujii took this photograph during the lunar eclipse of 30 December 1982.
Copyright 2010, Professor Kenneth R. Lang, Tufts University