The Rest Is Science

Earth’s Tilt Makes Time Slippery

The Rest Is Science

Show Notes

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

https://www.curiositybox.com/pages/closest-approach-to-uranus-------------------For more information about Cancer Research UK, their research, breakthroughs and how you can support them, visit https://cancerresearchuk.org/restisscience

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.

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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 Learn more about your ad choices. Visit podcastchoices.com/adchoices

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