A look at the evidence for the Earth being round or spherical. Aristotle's reasoning is explained. The evidence includes a ship's hull disappearing first over the horizon, the stars, the constellations and the shadow on the moon during an eclipse.

First broadcast:
5 March 2008

This clip could be used in a wider topic that investigates ‘Earth and space’. There could be an initial class enquiry to discuss why people in ancient civilisations thought the Earth was flat. Ideas could be recorded and a further discussion could ensue as to how people might have found evidence to show that the Earth is a sphere. Following this research and thinking, the clip could be shown and paused at each point - showing Aristotle's logic about the hull of a ship disappearing over the horizon first. Pupils could record the diagrams. Similarly, they could do this with Aristotle’s other ideas about different constellations being seen in the northern and southern skies. Further detailed research could be undertaken on eclipses.