Who Declassified Pluto as a Planet?

In August 2006 the International Astronomical Union (IAU) downgraded the status of Pluto to that of “dwarf planet.” This means that from now on only the rocky worlds of the inner Solar System and the gas giants of the outer system will be designated as planets.

Who declared that Pluto is not a planet?

In 2006 the International Astronomical Union (IAU) demoted the much-loved Pluto from its position as the ninth planet from the Sun to one of five “dwarf planets.” The IAU had likely not anticipated the widespread outrage that followed the change in the solar system's lineup.

Has Pluto been reclassified as a planet?

This led the International Astronomical Union (IAU) in 2006 to formally define the term "planet"—excluding Pluto and reclassifying it as a dwarf planet. Pluto is the ninth-largest and tenth-most-massive known object directly orbiting the Sun.