In 1930, and American astronomer by the name of Clyde Tombaugh discovered a body orbiting well beyond the orbit of Neptune. At the time, both he and the public assumed that the new body was indeed the ninth planet in the solar system. However, this new discovery didn’t quite explain some disturbances in the orbit of Uranus, and Neptune. It was assumed that whatever was lurking out there would be much bigger.
We zoom to today, and Pluto is no longer a planet. In fact, we really don’t know what it is, or what to classify it. Despite recent attempts to classify it as a comet, a dwarf planet, or the first of discovered KBO’s or Kuiper Belt Objects, we aren’t sure what fits it the best. What makes it even trickier when trying to describe Pluto is that it has a moon, but it too is weird for a moon.
Pluto orbits in a 3:2 resonance with Neptune, meaning that for every three orbits of the Sun that Neptune makes, Pluto will make two orbits. This means that Pluto will never hit Neptune, but Pluto does come within the orbit of Neptune, making it at times the 8th closest planet, if it were a planet. What is odd is that most objects in the Kuiper Belt that orbit in the same region of space as Pluto also have this same orbital resonance.
Take into account the odd orbit of Pluto, and how it doesn’t match up to any of the other orbits of the planets. All the planets orbit in more of a circle, while Pluto is in a wild elipse shape. Also the planets tend to orbit in the same plane of space, while Pluto does not. Pluto’s orbit is inclined 17 degrees with respect to the main plane of the solar system.
I think we can be safe in saying that Pluto is not a planet, and that although it has a moon, it is part of a yet to be understood binary system, as opposed to a planet-moon system. Pluto is most likely the first discovery of objects in the Kuiper Belt, or an outer region in space where debris from the making of the solar system is waiting to be found. It is also a region in space where most long period comets are believed to be lurking.
I do think though that Pluto will be a planet in the hearts of many people though. It has been a planet too long to be reclassifed anywhere else but in the scientific community. Tombaugh was the first American to discover a planet, and so I believe that at least in the US, there will be a fair amount of resentment for the reclassifying of Pluto. Whatever it is, it is a matter of semantics anyway, and no matter what you call it, Pluto will always be the same.
