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Tombaugh

[tom-baw]
noun
  1. Clyde William,1906–97, U.S. astronomer: discovered Pluto 1930.
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Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for tombaugh

Tombaugh

noun
  1. Clyde William. 1906–97, US astronomer, who discovered (1930) the dwarf planet Pluto
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Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
tombaugh in Science

Tombaugh

[tŏm′bô′]
  1. American astronomer who discovered Pluto in 1930. Beyond the orbit of Neptune, the existence of a planet known as Planet X, had been predicted some years earlier by the American astronomer Percival Lowell based on apparent perturbations in the orbits of Neptune and Uranus. Tombaugh's careful analysis of celestial photographs did reveal a new celestial body, although it was too small to have caused the perturbations. Planet X itself was never found.
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