10 FAQs about Planet-X (The Astronomy Cafe)

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 Back to the Astronomy Cafe - 365 of the most popular questions since 1996. Over 1 million page requests!

  1. [Updated]Are astronomers still searching for a 10th planet?
  2. Over the years, how many hypothetical planets have been searched for but not found?
  3. Where is the 10th planet located?
  4. What is the name of the 10th planet in our solar system?
  5. Was there ever a planet between the orbits of Mars and Jupiter?
  6. Is there a planet named 'Clara' outside the orbit of Pluto?
  7. Does Planet X exist?
  8. What objects have been explored outside Pluto's orbit?

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