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NOVA
What Are UFOs?
Season 52
Episode 1
After decades in the shadows, UFOs are being studied seriously. Are they weather balloons, optical illusions, secret military technology? Or something else? Follow scientists as they try to unravel the mystery of the strangest objects in our skies.
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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.
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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.
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53:31
Who created the Nazca lines and why? New clues to one of the greatest ancient enigmas.
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53:43
A team tackles the restoration of iconic Notre Dame Cathedral.
53:43
Ancient footprints provide new evidence of humans and extinct giant beasts of the Ice Age.
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53:20
How could a single ship cause a major supply chain crisis around the globe?
53:16
Sir David Attenborough explores a site with traces of ancient mammoths and Neanderthals.
53:30
In the Arctic, enormous releases of methane, a potent greenhouse gas, threaten the climate
53:31
Explore great ancient Maya cities and why their inhabitants abandoned them.