Pluto was discovered on February 18, 1930 by Clyde Tombaugh at the Lowell Observatory in Flagstaff, AZ. A planet beyond Neptune had been theorized since the 1840s. Percival Lowell himself searched for a number of years. He caught faint image of Pluto in 1915 but, sadly for him, they were not recognized as the ninth planet. Tombaugh's discovery was confirmed by followup photographs, and was announced on March 13, 1930. In the years since, the Kuiper Belt has been discovered: a very large belt of objects from asteroids to dwarf planets. Pluto is one such planet in the belt. The object Eris is larger than Pluto. Since other planets and their moons (if any) have a "clear" orbit of their own around the Sun (unlike Pluto and its many Kuiper objects), the International Astronomical Union "demoted" Pluto to dwarf planet status. A certain amount of unhappiness resulted, even including resolutions in state legislatures to affirm Pluto as a planet! Pluto orbits the Sun once in 248 Earth years. So it has made a little over 1/3rd of its journey since 1930. During some Earth years, Pluto's atypical orbit brings it closer to the Sun than Neptune. It has five satellites, and a surface temperature that can reach 33 degrees K (-400 degrees F).
Picture from: https://en.wikipedia.org/wiki/Pluto#/media/File:Pluto_in_True_Color_-_High-Res.jpg
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