For millennia, humans have been firmly rooted to the Earth, but haven't you ever fancied a change of scenery?

This month, science writer and broadcaster Dallas Campbell talks to former Christmas Lecturer and fellow space nerd Kevin Fong about all things space travel, and Dallas’ new book: Ad astra: An illustrated guide to leaving the planet.

Dallas Campbell is an actor, author and TV presenter, and has always been fascinated by space. He was also an understudy for the 2014 CHRISTMAS LECTURES: How to hack your home, and appeared via hologram in the final show.

Kevin Fong is an anaesthesiologist and space medicine expert. He presented the 2015 CHRISTMAS LECTURES: How to Survive in Space and regularly presents documentaries for Horizon and the BBC World Service.