You may have heard the phrase ‘we know more about the moon than the deep sea’ – it’s now an old phrase, dating back to 1948. In fact, we actually know quite a bit more about the ocean than you might think – which physicist and oceanographer Helen Czerski shows in her new book Blue Machine. But it’s still full mysteries, and that’s why Helen says that the secrets of the moon and the ocean are incomparable, because when it comes to the ocean there is just so much more to know, and we urgently need to uncover more.

In this episode we speak to Helen about some of the secrets hidden – and found – in the ocean’s currents, including shipwrecks and missing planes, what we’ve learned from rubber ducks and Finding Nemo, and the swirling currents in underwater rivers and waterfalls.

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