Like why is it not included in solar system i don’t get it
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It’s literally just semantics. Scientists choose some arbitrary size as the cutoff point between planet and not-planet. It doesn’t really mean anything in a scientific sense.
Planet is an arbitrary definition, chosen so that the Sun has only a handful of planets around it. If Pluto was a planet, the definition would be too broad and the sun would have hundreds of planets. So scientists decided a definition that would exclude Pluto and all of the extra almost-planets with it.
its not big enough to be constituted as a planet, there has to be a limit between planet and just a random space rock, and pluto is under that limit
Our solar system contains everything from gas giants like Jupiter to asteroid belts full of tiny rocks, and a whole manner of comets and other stuff flying every which way.
When Pluto was discovered, the definition of a planet was pretty much just ‘a big rock we have found orbiting the earth’, Pluto counted and so it got added into our map of the solar system.
Since then however, we have kept looking and found a whole lot more out there thanks to a lot more time spent searching and some much more advanced equipment. Lots of stuff being found meant we had to refine our definitions to draw a sensible line somewhere and avoid the map of the solar system hanging on our classroom walls getting too full of unremarkable small planets.
Sadly this more accurate definition of what is considered a full planet resulted in Pluto not making the cut and being downgraded. As such it is now considered a dwarf planet alongside others like Eris or Ceres.
Even though it is no longer officially a planet, it will still often feature on Marisa of the solar system and similar – either because there are still a lot of maps hanging on walls that were printed before it was redefined, or because it had historically been considered part of the solar system, and who lets a small detail like planet classifications get in the way of tradition.
All planets up to Neptune were formed at the same time as our sun. Hot gases from other stars condensed, flatted into a disk and then condensed into planets. Pluto was believed to have caught onto orbit afterwards. All 8 planets have the same orbital plane, whereas Pluto’s orbital plane is tilted.
Pluto is about the size of Australia.
We’ve realized, since it’s discovery, that small space rocks are, in fact, a dime a dozen.
Plus, it doesn’t even orbit on the same plane as every other planet in our system.
We really just got over-excited with the discovery and got ahead of ourselves.
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