What is the fastest, cheapest and possibly worst way to get into space? Could a nuclear explosion launch a manhole cover beyond the Earth’s atmosphere? And could space elevators, skyhooks or launch loops one day replace rockets? In this episode, Professor Hannah Fry and Michael Stevens (VSauce) explore where space really begins, why orbit means falling forever, and how Newton’s cannon explains the motion of the International Space Station. They also interrogate the physics of the Kármán line, orbital velocity and geostationary orbit, before asking whether humans could ever climb a staircase to space, or catch a rotating skyhook into orbit. Plus, the far future fate of Earth, firing a bullet around the Moon, the true value of the Apollo Moon landing, the ethics of colonising Mars and whether the future of space exploration should belong to private companies or the public! ------------------- For more information about Cancer Research UK, their research, breakthroughs and how you can support them, visit ⁠https://www.cancerresearchuk.org/our-research/rest-is-science Cancer Research UK is a registered charity in England and Wales (1089464), Scotland (SC041666), the Isle of Man (1103) and Jersey (247). A company limited by guarantee. Registered company in England and Wales (4325234) and the Isle of Man (5713F). Registered address: 2 Redman Place, London, E20 1JQ. ------------------- Video Editor: Oli Oakley Animator: Sam Benson Video & Social: Bex Tyrrell Assistant Producer: Lucy Lipscombe Producer: Simona Rata Senior Producer: Lauren Armstrong-Carter Chief Digital Officer: Samuel Oakley Exec Producer: Neil Fearn