Mapping out the Milky Way

This autumn, the Gaia spacecraft will be launched on a mission to find out where the Milky Way's stars came from. I catch up with two of the astronomers at the Lund Observatory who've worked on designing the spacecraft, and with one of the astronomers who's hoping to use data from the spacecraft to calculate where and when the stars of our galaxy formed.Plus, I hear about a new technique which is being used to work out what the atmospheres of planets around other stars are made of, and about observations of a recent gamma ray burst which are helping us to unravel what triggers these strange cosmic phenomena.