In this episode: 00:46 Optical clocks at seaOptical atomic clocks are the most precise timekeeping devices on the planet, but these devices are huge and difficult to work with, limiting their use outside of the lab. Now, researchers have developed a portable optical clock and demonstrated its...

Humans setting up home in outer space has long been the preserve of science fiction. Now, thanks to advances in technology and the backing of billionaires, this dream could actually be realised. But is it more likely to be a nightmare? Kelly and Zach Weinersmith join us to discuss their new book...