I’m of the believe that we made up the word planet and it can mean whatever we say it means.
I’m of the opinion we made up all the words, but those mouth sounds must have a strict meaning whenever possible. Words are important, they’re how you communicate concepts. Everyone should be precise with their words to the best of their understanding, if you have to redefine the word planet in every conversation the concept is diluted and you waste a lot of time
In this case, if Pluto is a planet, we have at least 13. We might discover another 10 or 20 if there’s no planet 9 hiding behind the kyper belt and it’s all dwarf planets… Ain’t no one got time to remember 30+ planets
That’s pretty much how it is. In ancient times, planets would have been objects that were distinguishable from stars in ways they had the ability to differentiate from. For example, with a telescope, any object that doesn’t shine like a star, that moves across the sky at a different rate than the stars, or maybe has visible rings.
Then once science found things that past science couldn’t account for, they redefined what a planet was, according to its size/gravitational pull or other factors, and which Pluto didn’t fit. Apparently due to Pluto’s small size, it’s not even a dwarf-planet, and by that measure is basically just a really big asteroid (we even know of asteroids that are bigger than Pluto).
The issue is, as I understand it, we either have 8 planets (or 9, if there is an exoplanet), or a whole bunch of planets, depending on how narrowly we define them.
Yeah this is the correct take. Either Pluto (and by extension, any object of similar size) is a planet, which would mean there’s thousands of Pluto-sized planets in the solar system; or pluto is ‘too small’ to be a planet. Which is the answer they (Sci community) settled on, because if every comet/asteroid is within the threshold definition of ‘planet’ then there would be no point in distinguishing planets at all.
Kinda like how we have dwarf-stars and supermassive stars 1000x bigger than our sun. If they were all the same size there would be no point defining them beyond ‘star’.
Pluto being too small isn’t actually the grounds on which it got demoted. The size requirement is just being massive enough to reach hydrostatic equilibrium - that is, be heavy enough that it’s round. Pluto does meet this one
The one it fails is clearing its orbit. This basically means being much heavier than everything else in the same orbit. Be gravitationally in charge of your orbit. The other eight are all hundreds if not thousands of times heavier than everything else in their orbit (not including moons, since they’re gravitationally bound to the planet anyway), whereas Pluto is less than a tenth of the total mass in its own orbit. Ceres is actually more gravitationally dominant over its orbit than that, although still nowhere near the eight planets.
This one sounds a bit weird at first, but I kinda like how it has such a massive delineation between the things we instinctively think of as planets and everything else.
