In short, yes.
In 2012, I still see posts on Facebook disputing the decision of the IAU, declaring that Pluto would be demoted to dwarf planet status. I just wonder, if we were to suddenly find out tomorrow that hydrogen was actually never an individual element in and of itself, but has been a helium isotope all along, would there be such large-scale protesting? Of course not. Nobody cares about hydrogen. They should, but they don’t. Hydrogen doesn’t appeal to the American spirit in the way that Pluto does, but why doesn’t it? It’s quite analogous.
Hydrogen is the smallest element known in the universe, consisting of one proton and one electron. It’s a tiny little guy who is light and sears off into space as soon as it can. Its isotopes can fuse together to become helium, the first noble gas, but to this day, hydrogen is hydrogen, and is element one. It’s rare on earth, but is quite abundant when combined with other elements, such as oxygen (water). The point is that hydrogen is very, very small – the smallest – so why doesn’t it appeal to the American spirit in the same way as Pluto? Well, because there isn’t a Disney character named after hydrogen. Also, because hydrogen is one among over 100 known atoms, whereas Pluto was one planet among 9. Nine is easier to remember than 118 elements, plus a couple hundred isotopes. Maybe because the periodic table isn’t as pretty as almost completely round objects elliptically orbiting a bright, shiny star.
Here are the facts:
Pluto has moons, yes, and it is also mostly round – two things that would classify it as a planet. Here’s the problem, however: it is smaller than many other objects in the Edgeworth-Kuiper Belt. Another problem is that another thing that would classify something as a full-fledged planet, is that it must clear other objects from its orbit. Pluto does not. It’s too small. Massive enough to be round, but still too small to clear its own orbit. In fact, it crosses an orbit with another planet.
The issue with Pluto is its size when compared to the known planets in our galaxy. There have been thousands of other planets observed by scientists in other solar systems, and Pluto still is still classified as a dwarf planet, and probably always will be. Pluto is a tiny, tiny astral body of just under 2,400 km, meaning it’s about the size of 70% of our moon. To give a more adept approximation, it’s only 18% the earth’s diameter. Pluto, being classified as a full-fledged planet hardly makes any sense. If our moon were to orbit the sun instead of the earth, and be rounder, it could be defined as a full-fledged planet if Pluto were.
Reasonable argument, the only:
“We cannot merely change the status of the a planet only to keep the number of full-fledged planets low and simple. We don’t do that in chemistry or physics, so why should we do it in astronomy?”
This is actually a good point, however, the reasoning behind demoting Pluto wasn’t to keep full-fledged planets at a manageable number. There are bodies in the Kuiper belt that are much larger than Pluto, that would suddenly become planets if we were to continue to classify Pluto as one. The fact is that we classify stars according to their size. There are dwarf stars, yellow dwarf stars, red dwarf stars, red giant stars, blue giant stars, and supergiant stars. We keep these classifications for reference. We classify them according to their size, their gravity, and numerous other matters. For instance, when we talk about a supergiant going supernova, we know what the outcome will be: a black hole. If we were to simplify the classifications by say, just two types of stars, then confusion would set in when we talk about the “giant” stars going supernova. What would happen?
We must classify planets by different types for the same reason we classify noble gases, transition metals, lanthanoids, actinoids, and other classifications of elements. Classification groups certain types of elements together so that we can gauge their reactions to other elements merely by their grouping. We can also gauge the chances of the element becoming radioactive because of these classifications. The noble gases are just peachy and fine on their own, other non-metals just love a good bonding experience.
Doing the same to planets is essential to keep our understanding of them in line. This type does this and has this mass. This other type does this and has this mass. Classification is essential to make scientific education palpable and accessible.
Sometimes classifications change as we learn more about the universe. Hell, classifications often change on much, much smaller levels here on earth, but nobody seems to notice. Science is ever-evolving because our understanding of the world and the universe around us is ever-evolving. There is always new information to be had, and what we know right now in the scientific community, no matter how expansive our knowledge, is subatomic when compared to all of the knowledge there is to be had. We can’t let sentiments get in the way of progress.
Pluto was a planet when I was a child as well, but that doesn’t mean I should resist this knowledge merely out of emotion. When my grandfather was a child, it was believed that separate species of human ancestors never walked together, yet now we know that not only did they walk with one another and fight with one another, but they interbred with one another. Should we protest this knowledge because it’s different from the knowledge we were taught as a child? Of course not. That would be a little silly, wouldn’t it? Well, I fail to see how Pluto is any different. Pluto is a dwarf planet, plain and simple. That doesn’t mean it’s gone anywhere. Trust me, it’s still there, and it’s still orbiting the sun along with us. Just very, very slowly.
If string hypothesis were to ever be proven (not likely), should we rebel in protest to sustain the standard model, even though it’s been shown to be – though only in this one instance – flawed? I’ll throw it down the toilet tomorrow if you can make string hypothesis a legitimate theory. Science requires progress and we must move along with it.