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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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53:47
See how Earth transformed from a barren hellscape to a planet capable of sustaining life.
53:31
Dive into the subconscious to see what’s really driving the decisions you make.
53:30
Neuroscientists discover the tricks and shortcuts the brain takes to help us survive.
53:19
Investigate one of the most powerful volcanic eruptions in recorded history.
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53:31
Follow scientists determined to save the critically endangered right whale.
53:31
Here’s how the U.S. could reach net-zero carbon emissions by 2050.
53:31
Americans use ancient wisdom and new technology to fight extreme weather.
53:31
See the latest stunning images and discoveries from the James Webb Space Telescope.
53:21
Archaeological discoveries reveal traces of ancient civilizations in the Amazon.
53:20
Thousands race to build Europe's biggest construction project–London's new railroad.
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53:32
Discover how the concepts of zero and infinity revolutionized mathematics.
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53:22
What exactly is crypto, and how does it work? This technology is more than just money.