What if the Earth spun backwards?

What if the Earth spun backwards?

Author: BBC World Service July 18, 2025 Duration: 26:29

Your whole life is governed by spin. The rotation of our planet tells you when to wake up, and Earth’s orbit around the Sun is the reason why some of us dig out a jumper for half the year and a t-shirt for the rest. But what if that all changed? That’s exactly what 8-year-old Geronimo in Ecuador wants to know. He and his dad, Fabian, have got themselves dizzy trying to figure out what would happen if the Earth stopped spinning, or better yet, started spinning in the opposite direction. Would everyone fly off into space? Would school be at night? Eager for answers, they decided to ask CrowdScience.

Presenter Anand Jagatia embarks on an interstellar journey, blasting off with the celestial origins of spin itself. Astronomer Amy Bonsor from the University of Cambridge in the UK explains how Earth’s rotation began, with collapsing clouds of gas, planetary pile-ups and crushing gravitational force.

At Keele Observatory, things get apocalyptic. Anand meets astronomer Jacco van Loon, who explains what would happen if Geronimo somehow waved a magic wand and brought Earth’s rotation to a halt. With months of unbroken daylight or darkness, devastating storms and even the loss of the Earth’s magnetic shield, it’s like the script of a disaster movie.

Wave that magic wand again and we imagine a world where the Earth not only stops... but starts spinning the other way. Meteorologist Joao Basso from the University of Leipzig in Germany walks us through a mind-bending 2018 study that tells us the surprising things that would happen to the global climate.

Presenter: Anand Jagatia Producer: Harrison Lewis Series Producer: Ben Motley


Curiosity drives discovery, and CrowdScience from the BBC World Service is built entirely on that principle. Each episode begins not with a scripted lesson, but with a question sent in by a listener from anywhere in the world. These aren't simple queries with easy answers; they are the wonderfully complex, often quirky puzzles about everyday phenomena and cosmic mysteries that make us all stop and wonder. What does silence sound like? Could we ever photosynthesize like plants? How does a crowd's mood physically spread? The team then embarks on a genuine investigative journey, tracking down the specialists at the very edge of our understanding-neuroscientists, ecologists, physicists, and engineers-to piece together credible, compelling answers. Listening to this podcast feels like having a direct line to the labs and field sites where knowledge is being created. The conversations are deep yet accessible, transforming abstract concepts into relatable stories. It’s a collective exploration where listener curiosity sets the agenda, making each episode a unique and democratic look at the machinery of our world and beyond. You become part of a global community pondering life, Earth, and the universe, one thoughtful question at a time.
Author: Language: English Episodes: 100

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