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NASA's Unexplained Files

Did Earth Have Two Moons?

Season 4 Episode 6
A startling discovery suggests that the hellish clouds of Venus may be the origin of life on Earth. A bizarre sighting 2,000 years ago raises the possibility that Earth once had two moons. A scientist helps the FBI crack the 1996 Olympic bombing.
  • 43 min
  • TV-PG
  • Premiered 10/04/2016