Physicist Dr Jen Gupta and comedian Alice Fraser travel the worlds of science and sci-fi.
Melvyn Bragg and guests discuss Black Holes, the ghosts of massive stars.
Professor Stephen Hawking delivers the second of his BBC Reith Lectures on black holes.
Professor Stephen Hawking delivers the first of his BBC Reith Lectures on black holes.
Ben Miller looks at black holes and the beginning of time.
Melvyn Bragg and guests discuss the creation and destruction of galaxies.
Sir Roger Penrose talks to Jim Al-Khalili about black holes and flaws in quantum physics.
Heather Couper considers how the concept of black holes gained credence in astronomy.
The science sleuths investigate the question 'What's inside a black hole?'.