This film tells of hostile new worlds that have been discovered on the edge of the Universe and explores the tantalizing possibility of one day finding a planet like Earth.
A look at how our solar system is teeming with thousands of asteroids and comets, it is now thought these mini-worlds played a vital part in kick-starting life on our planet.
Cosmologists answer questions about the shape and size of the cosmos, and how, by decoding radiation from the dawn of time - 15 billion years ago - they can discover the limits and the ultimate destiny of the Universe.