when was pluto discovered and who discovered it
Pluto Pluto was discovered by Clyde Tombaugh in 1930 and was originally considered to be the ninth planet from the Sun. After 1992, its status as a planet was questioned following the discovery of several objects of similar size in the Kuiper belt. In 2005, Eris, a dwarf planet in the scattered disc which is 27% more massive than Pluto, was discovered. This led the International Astronomical Union (IAU) to define the term "planet" formally in 2006, during their 26th General Assembly. That definition excluded Pluto and reclassified it as a dwarf planet.
Discovery and exploration of the Solar System Edmond Halley realised in 1705 that repeated sightings of a comet were recording the same object, returning regularly once every 75â€“76 years. This was the first evidence that anything other than the planets orbited the Sun.[5] Around this time (1704), the term "Solar System" first appeared in English.[6]