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NOVA

Season 4, episode 4. This player now records resume state for the active profile so browse, account, and detail pages can bring you back here quickly.

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S4 E4

The Sunspot Mystery

NOVA explores the research on the 1976 drought in the western United States which led some solar scientists to discover the link between weather patterns and the 11 year sunspot mystery.

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Season 4

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Episode 1: Hitler's Secret Weapon

Episode 2: The Hot Blooded Dinosaurs

Episode 3: What Price Coal?

Episode 4: The Sunspot Mystery

Now playing

Episode 5: The Plastic Prison

Episode 6: Incident at Brown's Ferry

Episode 7: Bye Bye Blackbird

Episode 8: The Pill for the People

Episode 9: The Gene Engineers