The 170-Year Search for a Planet Beyond Neptune

Planet Nine’s existence is not the first time astronomers have predicted a planet they couldn’t see. Clyde Tombaugh was looking for Planet X when he accidentally found Pluto. After Voyager 2 flew by Neptune in 1989, new calculations determined there was no Planet X. But three years ago, a disturbance was detected at the far reaches of the Solar System.
Aired: 6/10/2019 | 0:02:29
You may also like
  • Life on the Reef
  • On Call: Health + Medicine
  • Neanderthal
  • Twice Born: Stories from the Special Delivery Unit
  • Breakthrough: The Ideas That Changed the World
©2019 WNET All Rights Reserved.   825 Eighth Avenue, New York, NY 10019