Earth’s Tilt Makes Time Slippery
A sundial can be almost 16 minutes fast in November and 14 minutes slow in February, yet there's nothing wrong with it. So why does the Sun, our oldest timekeeper, disagree with the clock on your wrist?
In this episode, Professor Hannah Fry and Michael Stevens (Vsauce) explore the equation of time - the strange relationship between Earth's tilt, its orbit around the Sun and the way we measure our days.
Why does a day last 24 hours? Has it always been that way? And how can a piece of ancient coral reveal that time itself has changed?
To find out, Hannah and Michael investigate an ingenious sundial that appears to correct its own mistakes, and discover the extraordinary places on Earth where shadows disappear completely.
Along the way, they explore why sailors relied on the stars, the Moon's remarkable journey across London's sky, and the curious fact that the Pacific Ocean is so enormous it meets itself on the other side of the world.
Michael's references:https://rl.se/subsolarpoint
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Video Producer: Adam Thornton + Oli Oakley + Jack MeekAnimator: Sam BensonVideo & Social: Bex TyrrellProducer: Simona Rata + Lucy LipscombeSenior Producer: Lauren Armstrong-CarterChief Digital Officer: Samuel OakleyExec Producer: Neil Fearn
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The Rest Is Science
Join mathematician Professor Hannah Fry and science creator Michael Stevens (Vsauce) as they dig into the weird scientific questions that often go unexplored.
Welcome to The Rest Is Science, a show that sits in the fascinating space between what we think we know, and what we actually know. Why do we assume we understand things like time, randomness, or even gravity? Once you start questioning these familiar ideas, reality becomes astonishingly strange and completely fragile.
Whether you're a lifelong science fan or just naturally curious, The Rest Is Science will change your perception of reality, and prove that the biggest questions are always the most fun.
- No. of episodes: 100
- Latest episode: 2026-10-25
- Technology Science
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