Who discovered all the planets?
Most of the planets have been known about since ancient times. Only three have acually been "discovered."
Uranus was discovered accidentally in 1781 by William and Caroline Herschel. People had seen it many times before, but had just thought it was a star.
Neptune was mathematically predicted by John Couch Adams and Urbain Jean Joseph Le Verrier. You see, Uranus had been discovered 60 years before this time. According to the math equations, the orbit of Uranus was a little bit off. Based on this, Adams and Le Verrier figured there must be another planet which was affecting the orbit of Uranus. They calculated where it should be, then asked an astronomer to check. Neptune was discovered in 1846, almost exactly where it was predicted to be.
Clyde Tombaugh found Pluto in 1930 by taking lots of pictures of the solar system. He looked for anything that moved with respect to the stars, and found Pluto.
Submitted by RG (Colorado, USA)
(November 13, 1998)
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