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NOVA
Mysteries of Sleep
Season 47
Episode 4
From fruit flies to whales, virtually every animal sleeps. But why? Why do we need to spend nearly a third of our lives in such a defenseless state? Scientists are peering more deeply into the sleeping brain than ever before, discovering just how powerful sleep can be, playing a role in everything from memory retention and emotional regulation to removing waste from our brains.
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53:40
Archaeologists investigate the dramatic origins of democracy in ancient Greece 2,500 years ago.
53:08
Follow the Artemis mission to bring humanity back to the Moon for the first time since Apollo.
53:25
Surprising evidence at the world’s oldest temple overturns our understanding of human history.
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53:39
New evidence sheds light on the remarkable life—and mysterious collapse—of the ancient jungle city.
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53:31
What if violent asteroid impacts actually jump-started life on Earth? Explore a dramatic theory.
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53:41
See how ingenuity and teamwork keep the crew alive and doing science 250 miles above Earth.
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53:40
Astronauts and Mission Control relive terrifying moments during construction of the ISS.
53:28
Find out why deadly flash floods are on the rise and how we can protect ourselves from them.
53:21
Explore mysterious 9,000-year-old Stone Age megastructures found in the Arabian Desert.