You're viewing a single thread.
Pluto is a planet!
Yes, a dwarf planet!
And Jupiter is a Gas Giant, but we still count it as one of the planets of our solar system
Because if dwarf planets counted, we'd have to include a hell of a lot more than 9 planets.
NASA says there are only 5 dwarf planets in the system. But, it's all pretty arbitrary. The line between planet, dwarf planet and asteroid are all pretty fuzzy.
An alien civilization looking at the Sol system might say that it's only got one planet, Jupiter. Everything else is so much smaller that they're not really significant.
Another logical cut-off would be that planets had to be bigger than any moons in the system. If we went by that standard, Jupiter, Saturn, Uranus, Neptune, Earth, Venus and Mars could all still count as planets, but Mercury would get ditched because it's smaller than Ganymede and Titan.
What's funny is that we're still using the name "planet" which comes from "asteres planētai", meaning "wandering star". For the Greeks what mattered wasn't the size or the mass, it was how bright they were. That meant that a tiny object near the sun like Mercury (Hermes) got the name planet, because despite being tiny, the fact it's close to the sun means it reflects a lot of light. And Jupiter (Zeus) and Saturn (Cronus) got named not because they're so big, but because they're big and far away from the sun, which means they reflect sunlight in a similar way to the much smaller inner planets. Earth's moon might have been given the name "planet" if it had been a lot smaller and/or further away.
And we should.
The most performative "hurr durr science" bullshit ever. Who fucking cares if Pluto was considered a planet when you were a kid?
Not you specifically. There are people who really seem to care about this shit.
The only reason Pluto is no longer a planet is because we discovered there were loads more planets and couldn't be bothered to acknowledge their existence!
It's been like that for decades to be honest. Ceres used to be called a planet, but you don't see anyone complaining about it's demotion
i've spent 25 years on this blue marble fascinated by space, and only recently discovered there multiple long orbit dwarf planets going around the sun??? that is so cool why is this not widely known!
Unpopular opinion: dwarf planets are cool.
but so what?
we used to have a handful of elements, but when we kept discovering more, we didn't change the rules to have elements, and "strange elements" so schools only have to teach about 16 elements.
It's all just made up categorization. It's like that because astronomers have agreed to categorize them like that. That's all.
Well elements are elements. All of them are just protons and neutrons and electrons at the end of the day. They have different properties but all of them behave by the same rules.
But there's some big differences between the various kinds of bodies orbiting the Sun and how they're orbiting the Sun. Big asteroids were considered planets, until we discovered there's a shitload of them and they're all in roughly the same area. When it turned out Pluto is basically in the same situation and there's a lot more of the transneptunian objects, it was pretty clear that Pluto isn't special. If you compare it to planets it's pretty weird. But I think it's good that they created the dwarf planet classification because that also elevated Ceres back, hell yeah.
I'd rather we have dozens of planets, with news articles talking about "new planets discovered"
we can still teach the handful of "classical planets", so we can have posters, or have like periodic tables, and everyone be aware that they might go out of date as more is discoverd.
the solar system will be more exciting and more varied.
also, the "clearing orbit from similar objects" is time and orbit dependent,
larger orbits take longer to clear, which mean in a few billion years ceres might eject pluto and become a planet?
or we could have gas giants beyond pluto (like this hypothetical 9th planet ) which it would be unlikely it has cleared its orbit, so we could have a planet larger than Jupiter which we would call a planet, but if we discover another planet in its orbit (too large to clear), then we will have to say that it is a dwarf planet.
Pluto is a
planetplant!Pluto's not a planet, but he doesn't care because he knows he's hot shit.
