In this first video of the series, Lucy Hawking talks to science buff and TV presenter Dallas Campbell about what it takes to be an astronaut. Dallas explains everything you need to know to help you complete chapter one of your Principia Mission Space Diary - from exercise and healthy eating to designing an awesome space suit! The Principia Space Diary project is supported by the UK Space Agency and the European Space Agency. The videos are shot among the amazing collections at the Science Museum in London. Visit http://www.principiaspacediary.org for more information.