It was a burning question of mine for a while now:
I understand that dwarf planets like Pluto and Ceres aren’t considered planets of the solar system, but why are they called ‘dwarf PLANETS’ if they aren’t planets.
And no one really says, “the sun isn’t a star, it’s a Dwarf Star”. Nor is it declassified as one because of it.
So, why are dwarf planets not planets, but dwarf stars are stars?
Its semantics, and a subject of ongoing debate.
Per wikipedia, I really like this proposal:
Astronomer Jean-Luc Margot proposed a mathematical criterion that determines whether an object can clear its orbit during the lifetime of its host star, based on the mass of the planet, its semimajor axis, and the mass of its host star.[210] The formula produces a value called π that is greater than 1 for planets.[c] The eight known planets and all known exoplanets have π values above 100, while Ceres, Pluto, and Eris have π values of 0.1, or less. Objects with π values of 1 or more are expected to be approximately spherical, so that objects that fulfill the orbital-zone clearance requirement around Sun-like stars will also fulfill the roundness requirement[211] – though this may not be the case around very low-mass stars.
It basically means a planet should be big enough to consolidate all the stuff in its orbital area, not be part of an asteroid field. That makes sense to me.
https://en.wikipedia.org/wiki/Dwarf_star
“Dwarf” stars are even more confusing, as it basically a synonym for “normal,” as opposed to “giant” stars (which are relatively puffy and big for their mass/temperature), or more exotic stars. But the term is also used for special cases, like the relatively exotic white dwarfs (remnants of exploded stars with very strange properties, extreme density, and not “burning” like a star traditionally does), or “barely a star” brown dwarfs.
TL:DR: If an astronomer asks you to name something, you should say ‘absolutely not.’
For instance, just wait until you get a load of what astronomers consider to be metals.
Why would I turn down such an opportunity? I’m great at naming things.
I’m absolutely naming something if I’m given the opportunity,
Planet Bob is not great but still way better than K-57743267.7654
Mostly because Pluto was called a planet for a while, and reclassifying it upset so many people that they couldn’t just go “it’s just an asteroid sorry”.
In addition to the other people you’re hearing, “dwarf planet” also has specific criteria associated with how the body interreacts with its solar system. A dwarf planet has to orbit its star directly and be big enough for its gravity to have pulled it into a roughly spherical shape, but small enough that it hasn’t cleared its orbit.
A dwarf star is just a star that’s not particularly big and bright for whatever reason. While the terminology is similar, the usage is very different.
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It’s basically it’s large enough to be round like a planet but can’t achieve orbital dominance like the big 8. So it looks like a planet but acts like an astroid. I think dwarf planet is a good term for them. Becase if they were a little bigger they would have all the same properties of a planet and are a lot closer to becoming a planet that than an asteroid.
Hell I think Jupiter shouldn’t be a planet. Since it’s really close to being a star. I think it should be classified as a protostar.
How much bigger would Jupiter have to be before fusion started?
Just the extra mass of 13 times I know doesn’t sounds like a lot but going from Earth to Jupiter’s is about 318 times. Maybe instead of protostar we should use failed star since it has all the hydrogen and seller dust of that a star would used forces fuel.
Well, for one, a dwarf star probably was a star to begin with, but ran out of fuel or something.
A dwarf planet, on the other hand, isn’t the same once you strip away the rocks that make it qualify.
I am almost certainly missing something given that this is based on stuff I read almost a decade or more ago.
