Melvyn Bragg and his guests discuss the Sun. The object that gives the Earth its light and heat is a massive ball of gas and plasma 93 million miles away. Thanks to the nuclear fusion reactions taking place at its core, the Sun has been shining for four and a half billion years. Its structure, and the processes that keep it burning, have fascinated astronomers for centuries. After the invention of the telescope it became apparent that the Sun is not a placid, steadily shining body but is subject to periodic changes in its appearance and eruptions of dramatic violence, some of which can affect us here on Earth. Recent space missions have revealed fascinating new insights into our nearest star. With: Carolin Crawford Gresham Professor of Astronomy and Fellow of Emmanuel College, Cambridge Yvonne Elsworth Poynting Professor of Physics at the University of Birmingham Louise Harra Professor of Solar Physics at UCL Mullard Space Science Laboratory Producer: Thomas Morris.