who was he?
American astronomer
Clyde Tombaugh
Clyde William Tombaugh (February 4, 1906 January 17, 1997) was an American astronomer.
what is the definition of a planet? A planet is a body that orbits the Sun, is massive enough for its own gravity to make it round and has "cleared its neighbourhood" of smaller objects approaching its orbit how were they described during antiquity? Ancient Greek astronomers employed the term "asteres planetai" meaning "wandering stars", to describe those starlike lights in the heavens that moved over the course of the year and during the middle ages? Medieval and Renaissance writers generally accepted the idea of seven planets what is one controversy that is going on regarding this? A number of Pluto-as-planet proponents have circulated a petition among astronomers to alter the definition when was this controversial entity discovered? 1930 by whom? Clyde Tombaugh
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Clyde Tombaugh [SEP] Introduction
Clyde William Tombaugh (February 4, 1906 January 17, 1997) was an American astronomer. He discovered Pluto in 1930, the first object to be discovered in what would later be identified as the Kuiper belt. At the time of discovery, Pluto was considered a planet, but was later reclassified as a dwarf planet in 2006. Tombaugh also discovered many asteroids. He called for the serious scientific research of unidentified flying objects, or UFOs.