Pluto: Planet or Not?

[Wind in the Willows]

Does it really matter?

[Divair2]

Does it really matter?

Not very.

[Basking Turtles]

Does it really matter?

Not a lot. We categorize things in order to make communication more efficient. The objects are what they are no matter how we choose to call them, of course.

[AiliailiA]

There are five orders of magnitude difference between the least-cleared planetary orbit (Neptune's) and the next most cleared orbit ... and that's not even Pluto. It's Ceres in the Asteroid belt! Pluto's orbit is another 4 times more cluttered than that, and probably more since only a tiny fraction of Kuiper Belt objects are known.

That's by Soter's criterion of observed material in orbits; the Wikipedia page explains how that is calculated and footnote 3 is Steven Soters actual article. It's 22 pages long so you may not actually want to read it, but it's freely available if you do.

However, because it is vague, it may be interpreted multiple ways.

Five orders of magnitude is not a "vague" distinction. In the top of the table you have eight objects with orbital clearances within 2 orders of magnitude of each other: planets.

Then there is a gap of 5 orders of magnitude: 100,000 times. Then Ceres, then Eris, then Pluto. Before Pluto was even discovered Ceres was termed an asteroid to distinguish it from planets. For one thing it's not ball shaped, but some astronomers still called it a planet. UNTIL other asteroids were discovered in the same orbital region.

With the same process of better telescopes and enormous patience, the same thing has happened to Pluto. The Kuiper Belt was discovered and Pluto is part of it. I'm sorry if you don't like it, but that's how it is.

You know you said "if Pluto is a dwarf planet then so is Earth"? Did you notice in the table that Earth's orbit is the most well-cleared of all? Yeah, so by that reasoning they're all dwarf planets ... including Jupiter ...

[Wind in the Willows]

Does it really matter?

Not very.

I don't really see why you had to emphasize the very, but alright then.

[Dragomere]

However, because it is vague, it may be interpreted multiple ways.

Five orders of magnitude is not a "vague" distinction. In the top of the table you have eight objects with orbital clearances within 2 orders of magnitude of each other: planets.

Then there is a gap of 5 orders of magnitude: 100,000 times. Then Ceres, then Eris, then Pluto. Before Pluto was even discovered Ceres was termed an asteroid to distinguish it from planets. For one thing it's not ball shaped, but some astronomers still called it a planet. UNTIL other asteroids were discovered in the same orbital region.

With the same process of better telescopes and enormous patience, the same thing has happened to Pluto. The Kuiper Belt was discovered and Pluto is part of it. I'm sorry if you don't like it, but that's how it is.

You know you said "if Pluto is a dwarf planet then so is Earth"? Did you notice in the table that Earth's orbit is the most well-cleared of all? Yeah, so by that reasoning they're all dwarf planets ... including Jupiter ...

correct, as that is how it can be interpreted even though they are planets.

[AiliailiA]

Does it really matter?

About as much as whether a cougar is a Big Cat or not. I.e. not really.

[Nigerian Kenya]

Pluto is not a planet. Just another object in the Kaiper Belt. It's not even the biggest thing there, and we don't call the biggest thing a planet either. If Pluto is a planet, so is the thing in the kaiper that is bigger than pluto.

[AiliailiA]

Pluto is not a planet. Just another object in the Kaiper Belt. It's not even the biggest thing there, and we don't call the biggest thing a planet either. If Pluto is a planet, so is the thing in the kaiper that is bigger than pluto.

Eris, sire.

It was the discovery of that which prompted the IAU to finally get around to defining "planet".

Maybe "dwarf planet" wasn't the best choice of words. Some people seem to find it insulting.

[Cetacea]

Pluto is not a planet. Just another object in the Kaiper Belt. It's not even the biggest thing there, and we don't call the biggest thing a planet either. If Pluto is a planet, so is the thing in the kaiper that is bigger than pluto.

Eris, sire.

It was the discovery of that which prompted the IAU to finally get around to defining "planet".

Maybe "dwarf planet" wasn't the best choice of words. Some people seem to find it insulting.

Yeah I would have preferred the term Planetoid

but then I didn't have a problem with adding Ceres, Eris, Haumea and Makemake to the list of 32 Planets either

but as it sits Plutos a dwarf

[Mkuki]

No, I do not think that Pluto is a planet.

[Slovinka]

wow so many people say no, we're taught that it is! I think if there are lots of scientist that claim it's not then we should be taught both sides

[Mkuki]

Pluto is not a planet. Just another object in the Kaiper Belt. It's not even the biggest thing there, and we don't call the biggest thing a planet either. If Pluto is a planet, so is the thing in the kaiper that is bigger than pluto.

Eris, sire.

It was the discovery of that which prompted the IAU to finally get around to defining "planet".

Maybe "dwarf planet" wasn't the best choice of words. Some people seem to find it insulting.

Eris is, if we go by radius, actually smaller than Pluto. Mass-wise, though, it is larger than Pluto.

[The Sotoan Union]

If Pluto is a planet then so are all the other dwarf planets. The solar system would have like 40 planets. Kids would spend as much time learning about Jupiter as they would a bunch of rocks.

[Divair2]

wow so many people say no, we're taught that it is! I think if there are lots of scientist that claim it's not then we should be taught both sides

No.

[Slovinka]

wow so many people say no, we're taught that it is! I think if there are lots of scientist that claim it's not then we should be taught both sides

No.

why not though? like say "it's said by some scientist to be a planet, BUT, X reason says no because yadda yadda"

[Sun Wukong]

wow so many people say no, we're taught that it is! I think if there are lots of scientist that claim it's not then we should be taught both sides

It's not a debate. There aren't two sides. The definition of "planet" has always been a bit arbitrary, so to make things more consistent, scientists decided to refine the definition, and Pluto no longer qualified.

It's sort of like when your insurance company determines that, because of their new policies, you no longer qualify for your current rate. You may not like their decision, but there's no debating it.

[Divair2]

No.

why not though? like say "it's said by some scientist to be a planet, BUT, X reason says no because yadda yadda"

It is not said by astronomers to be a planet. It was decided in 2006 that it is not a planet. It's not a matter of opinion.

[The Sotoan Union]

No.

why not though? like say "it's said by some scientist to be a planet, BUT, X reason says no because yadda yadda"

Be taught both sides? Should we also learn about all the historical theories on what blood does? If scientists say it's not a planet then it's not a planet.

[New haven america]

No, it's not.

[Mkuki]

No.

why not though? like say "it's said by some scientist to be a planet, BUT, X reason says no because yadda yadda"

That perpetuates myth and ignorance. Something schools shouldn't be perpetuating. Plus, some sides don't need to be given the floor for debate. Anti-vaxxers, for example, don't need to be given any credence when deciding policy in concern with vaccines.

[Slovinka]

It's not a debate. There aren't two sides. The definition of "planet" has always been a bit arbitrary, so to make things more consistent, scientists decided to refine the definition, and Pluto no longer qualified.

It's sort of like when your insurance company determines that, because of their new policies, you no longer qualify for your current rate. You may not like their decision, but there's no debating it.

I read they now call it a dwarf planet

[Sun Wukong]

It's not a debate. There aren't two sides. The definition of "planet" has always been a bit arbitrary, so to make things more consistent, scientists decided to refine the definition, and Pluto no longer qualified.

It's sort of like when your insurance company determines that, because of their new policies, you no longer qualify for your current rate. You may not like their decision, but there's no debating it.

I read they now call it a dwarf planet

Yes. That is the category it now falls under. They decided that it wasn't a true planet, because it can't clear it's own orbit, and all the other objects we call planets can.

[The Romanov Russia]

Despite it being a Minor Planet, Pluto is still a planet.

[Divair2]

Despite it being a Minor Planet, Pluto is still a planet.

Dwarf planet. Not a planet. Not a "minor planet".