Pluto’s status as a full-fledged planet was fleeting, lasting only a few decades. The planetary object was later classified as a dwarf planet in 2006. But only a few people know what a dwarf planet is, much less why the label played such a big role in Pluto’s fate.
Before being named the ninth planet in our solar system, Pluto was predicted by astronomers when they found that an object orbiting the sun was modifying the orbits of Uranus and Neptune. But later, scientists were finding more planetary objects that revolved around stars which led them to question what it means to be a planet.
Three criteria to determine planetary status were put into place by the International Astronomical Union. A planet must: orbit the sun, have a round shape, and clear its orbits of other objects. Pluto only fits the description of the first two.
Despite its great similarities to the others, Pluto’s cluttered orbit is what sets it apart from the rest of the planets in our solar system. It goes around the sun, it’s round, and it has moons, but the debate over our former ninth planet is yet to go full circle.