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NOVA
What Are UFOs? Preview
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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Journey back to the beginning of everything: the universe, Earth, and life itself.
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53:50
An American combat hospital mobilized in Iraq faces a daily drama of wartime treatment.
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Will experimental particle physics confirm the wild predictions of string theory?
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Do miniscule vibrating strands of energy hold the key to a unified theory of physics?
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Combining the laws of the universe in one theory that explains it all is the Holy Grail
