When I learned the order of the planets in elementary school, Pluto was still considered a planet. About 14 years ago, it was demoted to a dwarf planet. The International Astronomical Union has three criteria in determining planetary status. It is in an orbit around the sun, it has sufficient mass to assume hydrostatic equilibrium, and it has cleared the neighborhood around its orbit. To be a planet, you must have all three. Pluto actually orbits with other surrounding stuff in its “neighborhood”, meaning it can not count as a planet, and this, was given dwarf planet status. Jim Bridenstine from NASA argues that the IAU’s decision was unscientific, and was used as a means to keep the number of planet’s down to a manageable number instead of being forced to reevaluate the entire solar system. For now, Pluto remains a dwarf planet, but here is to Pluto lovers like myself: there is hope Pluto could once again be a planet.






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