What would it have been like to walk the lava-filled earth four and a half billion years ago?Or take your first step on the surface of the moon?And what would you do if robots took over the world? In their series of novels, George's Secret Key to the Universe, Lucy and Stephen Hawking imagined what great adventures one boy might have if he travelled through space. But the books were based on real-life facts - and together Lucy and Stephen collected an incredible wealth of information about everything from life on Mars to the secrets of black holes. For the first time this non-fiction content has been collected into one astonishing volume, with brand new content for 2020, including facts about genetics, conspiracy theories and climate change. Beautifully illustrated and absolutely bursting with amazing facts and figures, this is the perfect guide to everything you've ever wanted to know about our world and beyond.