In 1930.
Clyde Tombaugh discovered Pluto at the Lowell Observatory in Flagstaff, Arizona.
Never. Pluto was discovered by Clyde Tombaugh, in 1930.
None. Clyde Tombaugh discovered the body we know as Pluto. This was originally described as a planet but internationally it is now recognized that Pluto is not a planet but a dwarf planet. Therefore Clyde Tombaugh did not actually discover a planet!
Pluto, which is now classified as a dwarf planet.
Tombaugh was credited with discovering hundreds of asteroids, as well as Pluto in 1930, but no comets.
Clyde Tombaugh discovered Pluto in 1930.
Clyde William Tombaugh was the American astronomer that discovered Pluto!
Clyde Tombaugh
Pluto was discovered in 1930 by Clyde Tombaugh.Astronomers noticed that the orbits of Neptune and Uranus were being affected by the gravity of an unknown object in the Solar System. Clyde Tombaugh carefully studied images of the night sky, and after a lot of hard work he finally discovered Pluto.
Clyde Tombaugh was the astronomer who discovered Pluto in 1930, while working at Lowell Observatory in Arizona. Tombaugh also found a comet, hundreds of asteroids, and several galactic star clusters.
Clyde Tombaugh, an American astronomer, discovered Pluto in 1930 while working at the Lowell Observatory in Arizona. Pluto was the first object to be discovered in what would later be classified as the Kuiper Belt.
Pluto was discovered by Clyde Tombaugh in 1930 at the Lowell Observatory in Arizona. Tombaugh discovered Pluto by systematically searching for unknown objects in the outer solar system using photographic plates.