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Mysteries of Sleep

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Nature's Fear Factor

Nature's Fear Factor

Season 47 Episode 9
53:21
Human Nature

Human Nature

Season 47 Episode 11
1:33:41
Can We Cool the Planet?

Can We Cool the Planet?

Season 47 Episode 16
53:31
Beyond the Elements: Reactions

Beyond the Elements: Reactions

Season 47 Episode 17
53:31
Beyond the Elements: Indestructible

Beyond the Elements: Indestructible

Season 47 Episode 18
53:30
NOVA Season 47

Beyond the Elements: Life

Season 47 Episode 19
53:32
Looking for Life on Mars

Looking for Life on Mars

Season 48 Episode 2
53:46
Reef Rescue

Reef Rescue

Season 48 Episode 4
54:06
The Cannabis Question

The Cannabis Question

Season 48 Episode 11
53:36
Particles Unknown

Particles Unknown

Season 48 Episode 12
53:28
Edible Insects

Edible Insects

Season 48 Episode 14
53:28
Alaskan Dinosaurs

Alaskan Dinosaurs

Season 48 Episode 21
53:21
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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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