NOVA

How Atomic Clocks Keep Perfect Time

Modern timekeeping relies on the accuracy of atomic clocks, which revolutionized timekeeping by using the quantum behavior of atoms to measure time. Discover how these incredibly precise clocks work, and how they ensure global synchronization in everything from GPS to scientific research.

How Atomic Clocks Keep Perfect Time

2m 15s

  • What Are UFOs?: asset-mezzanine-16x9

    What Are UFOs?

    S52 E1 - 53m 43s

    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.

  • Lost Tombs of Notre Dame: asset-mezzanine-16x9

    Lost Tombs of Notre Dame

    S51 E18 - 53m 40s

    After the Notre Dame fire in 2019, two mysterious coffins were found buried beneath its floor. Where did they come from and who was inside? Follow scientists and historians as they investigate what their stories reveal about this iconic cathedral.

  • Hunt for the Oldest DNA: Extended Version: asset-mezzanine-16x9

    Hunt for the Oldest DNA: Extended Version

    1h 24m

    For decades, scientists have tried to unlock the secrets of ancient DNA. Follow the dramatic quest to recover DNA millions of years old and reveal a lost world from before the last Ice Age.

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