Pluto's Dwarf Planet

Towards the very end of our solar system is a dwarf planet named Pluto. The existence of the unknown planet was first proposed by astronomer Percival Lowell in 1905, who thought that the wobbles in the orbit of Neptune and Uranus were probably caused by the gravitational pull of an unknown planet. After calculating the approximate location, he looked for more than a decade without any success. About 25 years later, it was discovered by an American astronomer named Clyde Tombaugh. The surface temperature of the planet is estimated to be about -360 degrees Fahrenheit. Because it is so cold, Pluto was named after the Roman name for the god of the underworld. The reason why it is so cold is because it is 3.67 billion miles away from the Sun, and it takes around 248 years to complete one orbit. The dwarf planet travels around the Sun in an elliptical orbit, because of this sometimes its orbit comes closer to the Sun than Neptune’s. Pluto stays in Neptune’s orbit for about 20 Earth years. The
Soon after the discovery of the planet, controversy among astronomers arose. Is Pluto qualified to be a planet? For an object to be a planet it has to meet three requirements defined by the IAU (International Astronomical Union). It needs to be in orbit around the Sun, it needs to have already “cleared the neighborhood” of its orbit, and it needs to have gravitational pull strong enough to pull itself into a sphere. Pluto doesn’t apply to the second rule. “Cleared its neighborhood” basically means that as planets form, they become the dominant gravitational body in their orbit. So when they interact with smaller objects, they consume them or sling them away with their gravity. Pluto’s mass is only 0.07 times the mass of other objects in its orbit. Comparatively, the Earth has 1.7 million times the mass of other objects in its orbit. So any object that does not meet the 2nd rule is considered a dwarf