What's the difference between mist and fog? Would 1 kilometre on our orbit make the difference between life and death on Earth? How do washing powders get clothes clean? How does sunlight and seawater lighten hair? How deafening was the Big Bang? Will rainwater wash clothes better than tapwater? Why does water issuing from a tap when you first turn it on, look white with tiny bubbles? Why doesn't Super Glue go hard in the tube? Are gravitational waves audible? Like this podcast? Please help us by supporting the Naked Scientists