'Trapped for 63 days': How one man uncovered the body’s hidden clock
Produced by: Manoj Kumar
Time vanished
In 1962, Michel Siffre, a young geologist, vanished into a cave for 63 days—no clock, no sun, no contact—only to emerge unsure if he’d been gone weeks or years.
Mind unspooled
Cut off from the world, Siffre’s brain lost grip on time. He counted two minutes as five, journaling his descent into temporal confusion with eerie calm.
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Clockless body
His internal clock went rogue. Days stretched to 36 hours. He stayed awake for 30, slept 12—and never noticed the shift. His body had uncoupled from time.
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Cave-born science
This solo mission gave birth to chronobiology—the study of our body’s rhythms—redefining how we understand sleep, alertness, and mental stability.
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Cold and alone
In a freezing Alpine cave, soaked and shivering, Siffre took on one of the most extreme self-experiments ever attempted—all in the name of science.
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War meets time
His data stunned NASA and the French military. In the Cold War space race, they realized time perception might be the key to long-term isolation missions.
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Human lab rat
Though mocked at first, Siffre became the world’s first human chronobiology subject—a living blueprint for future studies on space travel and submarine life.
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Rhythm broken
Other volunteers joined later. One slept 33 hours straight. Another cycled through 25-hour days. The body, it seemed, didn’t care about the clock.
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Explorer of time
What began as geology turned Siffre into a pioneer of human time research—proving we aren’t ruled by hours, but by biology, memory, and darkness.
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