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NASA's Unexplained Files

Mars's Deepest Secret

Season 4 Episode 8
British astronomers working for the CIA intercept Soviet photos of the moon. A malfunction on the ISS could poison its crew with deadly ammonia gas. A startling image taken by a NASA probe points to evidence that life could exist on Mars.
  • 43 min
  • TV-PG
  • Premiered 10/18/2016