Melvyn Bragg and guests discuss astronomer Johannes Kepler.
Philip Ball's tale is of Kepler's Snowflakes, a New Year's gift and of crystallography.
Neil MacGregor examines how Luther created the modern German language.
Ernie Rea and guests discuss how Martin Luther affected the course of the Reformation.
Chris Bowlby explores how the Reformation shaped German culture and what it means today.
How a dying man's book demoted the earth and reconstructed the universe.
Copernicus had the crazy idea that the Earth was not at the centre of the universe.