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

Before watching this clip students could be asked to consider how we know that the Earth is a sphere. They could then consider if people thousands of years ago would have had this same evidence and if not what did they think the Earth looked like. Students could then recap the evidence that Aristotle believed proved the Earth was round. They could consider how people at this time would have reacted and write a fictional news report to break Aristotle's news, then read it to the rest of the class.