Should Pluto be a Planet?

[Arcturus IV]

There are ~7,000,000,000 people in the world. Naming them all will be messy.

Poor reasoning is poor.

Okay, give me one non sentimental reason why SCIENTISTS SHOULD CLAIM THAT AN ICECUBE AT THE EDGE OF OUR SOLAR SYSTEM SHOULD BE REINSTATED AS A PLANET, WHEN THE SAME ONES CLAIMED 7 YEARS AGO, THAT IT IN FACT ISN'T FOR A NUMBER OF VERY GOOD REASONS?!

If you're lucky though, it keeps crashing into similar dwarf planets and may clear it's way
and then in a few million years, it might, be a planet.

Calm down. All I said was that "naming ~200 objects as planets would be messy" is a poor reason. I didn't say there weren't any good reasons.

I do say, however, that the definition of a planet at this point is not comprehensive or definitive enough. Might as well modify this:

replacing the words with:

Matter
State
Scale
Density
Location
Relativity
Composition
Structural arrangement
Designation

Which would make Pluto matter, solid, macro, (density*), stellar orbital, long range elliptic orbit, rocky ice, (molecular arrangement*), 134340 Pluto.

*I'm not sure what its density and molecular arrangement are.

Also, scratch the whole naming system for everything and give all stellar, substellar, and superstellar objects alphanumerical identities. Names can be optional for near-Earth objects or sentimental identification.

[Grave_n_idle]

No. This isn't a matter of opinion. Scientific terminology is objective. Pluto is not a planet because it does not have enough gravitational pull to clear its orbit. End of story. It is not and never should have been a planet.

Exactly. It's science, not popularity.

[Dazchan]

1. See above.
2. No. See above.
3. Not irrelevant. Size is an important factor when deciding planetary status, and honestly right now? The whole system is a giant pile of steaming shit. There need to be better definitions, or the IAU needs to go back to the previous setup and stop pretending this current system is better. Because it isn't.

1. Your nonsense is still nonsense.
2. Your unsourced nonsense is still unsourced nonsense.
3. Until Alan Stern's "definition" is accepted by the IAU, it matters not what he says. In current scientific reality, size is only relevant when defining a planet in the sense that a planet must be massive enough to be near-spherical and to have enough gravity to clear its neighbourhood. "It's smaller than a couple of freakishly large moons" is not a criterion.

[Dakini]

Because there's a planetary mass object orbiting a brown dwarf?


Somewhat iffy claims since neither of these are well-defined or agreed upon definitions.


If the Sun was in Mercury's orbit, there would be no Mercury any more.

1 and 2. From the planetar wiki link:

planetars are planet-like objects that are formed in the manner of planets, through accretion or core collapse from a circumstellar disc. Both brown dwarfs and planetars are planet-like objects above a certain size.

The 2M1207b link defines said substellar object as a sub-brown dwarf. It's almost the same size as Jupiter.

No, first of all, it says that there are some questions, not that it is a sub-brown dwarf. Secondly, its estimated mass is almost an order of magnitude larger than Jupiter.

Further, neither sub-brown dwarf nor planetars are commonly used by the astronomical community and are therefore very sporadically defined. They also don't describe how people think Jupiter formed. The current ideas about how Jupiter formed are that it formed by accretion or small bodies that condensed out of the solar nebula (like Earth, but with some ices too) until it hit about 10 Earth masses, then it started directly accreting material onto its core. This is very different from directly collapsing out of the solar nebula.

The distinction between "this orbits a yellow G-type star" and "this orbits a brown dwarf" is pretty arbitrary.

That's not the distinction being made.

As for the definitions not being well defined or agreed upon, that is my point in arguing Jupiter is not a planet. Not everyone agrees on Pluto's demotion, and planets are relatively poorly undefined with arbitrary exceptions made by the IAU as they see fit.

The IAU doesn't give that much of a shit if "everyone" including people who aren't in astronomy think their definitions are good. The average person knows pretty much fuck-all about actual astronomy. Even a lot of people who are decent amateur astronomers are often really, really wrong (I've heard someone describe the ring nebula as a supernova remnant when it's really a planetary nebula).

They even overturned the popular vote to grant the name "Vulcan" to one of Pluto's moons for arbitrary and questionable reasons.

They didn't overturn anything. They said that they'd take suggestions from the poll, but that they might disregard them. Probably they noticed that there was active campaigning to fix the election or they just thought the second and third place ones were more appropriate.

3. The Sun isn't in Mercury's orbit, duh. I'm talking about gravity. I require evidence that Mercury itself has cleared its orbit, and that the orbit hasn't been cleared by dint of Sol's gravitational well, or passing asteroids or what have you.

All of the planets are in the Sun's gravitational well, that's why we're orbiting it.

Does the Sun orbit itself through any part of Mercury's orbit? No.

3. Not irrelevant. Size is an important factor when deciding planetary status, and honestly right now? The whole system is a giant pile of steaming shit. There need to be better definitions, or the IAU needs to go back to the previous setup and stop pretending this current system is better. Because it isn't.

The previous system where there was no definition and people did demote planets when they figured out they were part of say, the asteroid belt? You know, like what happened with Ceres? Back during a time before the internet when people didn't have time to raise a fuss about how they know better than some experts?

That previous set up?

[Dakini]

Because.


It's ellipse around the sun is very eccentric.
There are around 200 Pluto-like objects in the solar system, naming them all planets will be messy.

There are ~7,000,000,000 people in the world. Naming them all will be messy.

Uh, I don't think you read that right.

People name tons of these things (I have a friend who discovered two trans-Neputian Objects and I know she named one of them Panda, I forget what she called the other one). The ones that are round get some special IAU treatment where they make sure to name them after a variety of gods from different cultures now (which is why Xena and Gabrielle didn't stay Xena and Gabrielle), but they're still not planets.

[Dakini]

There are ~7,000,000,000 people in the world. Naming them all will be messy.

Poor reasoning is poor.

Okay, give me one non sentimental reason why SCIENTISTS SHOULD CLAIM THAT AN ICECUBE AT THE EDGE OF OUR SOLAR SYSTEM SHOULD BE REINSTATED AS A PLANET, WHEN THE SAME ONES CLAIMED 7 YEARS AGO, THAT IT IN FACT ISN'T FOR A NUMBER OF VERY GOOD REASONS?!

If you're lucky though, it keeps crashing into similar dwarf planets and may clear it's way
and then in a few million years, it might, be a planet.

Actually, it wouldn't because it's never going to accrete Neputne.

[The Turian Hierarchy]

I'd say Pluto doesn't really care what we choose to class it as. It'll keep hurtling around the solar system either way.

[Afalia]

Yes because without it, My Very Energetic Mum Just Served Up Nine Pizzas doesn't work!

[Utceforp]

Yes because without it, My Very Energetic Mum Just Served Up Nine Pizzas doesn't work!

I've very recently learned the new variation, which is My Very Energetic Mum Just Served Us Nachos. If we say Pluto is a planet, the other dwarf planets will have to be planets too, and then nothing works!

[Tlaceceyaya]

Yes because without it, My Very Energetic Mum Just Served Up Nine Pizzas doesn't work!

Use Mary's Virgin Explanation Made Joseph Suspect Upstairs Neighbour.

[Aequalitia]

Is it not hilarious this discussion got 15 pages already!

[Phocidaea]

I think they should revert to the old definition of planet as basically "spheroid and not orbiting another planet", and count all those tiny ones in the outer solar system as planets. Yes, I am fully in favor of classifying Eris, Ceres, et al. as planets under this definition.

[Meritocratic States]

This is how I see it when it comes to Pluto.

[Utceforp]

I think they should revert to the old definition of planet as basically "spheroid and not orbiting another planet", and count all those tiny ones in the outer solar system as planets. Yes, I am fully in favor of classifying Eris, Ceres, et al. as planets under this definition.

That is way, waaay too vague. If I somehow used a rocket to launch a rubber ball into orbit around the Sun, under this definition it would be considered a planet.

[The Imperial Republic of New Kyoto]

I still support Pluto as a classical planet but If Pluto must be removed because the IAU cannot handle it, then eradicate the use of the term "Dwarf Planet" Calling Pluto a Dwarf Planet but not a planet is counter intuitive. Pluto, Ceres, Eris, et al should be termed "Subplanets" much like India is a "Subcontinent" or some other term.

[Geilinor]

I think they were right, Pluto is similar in size to several objects near it ,and is too small and similar in shape to all the to all the other things out at the fringe regions of the solars system. all those small planets, like Eris for example, are not classified as planets. Nor should Pluto be.

I agree. All the new dwarf planets meant that Pluto couldn't rightly be a full planet. We wouldn't want the other dwarfs getting upset, would we?

[Geilinor]

Yes because without it, My Very Energetic Mum Just Served Up Nine Pizzas doesn't work!

If we say Pluto is a planet, the other dwarf planets will have to be planets too, and then nothing works!

This^. Classifying Pluto as a planet but not Eris would break the definitions and create contradictions. Eris is estimated to be 27% larger than Pluto.

[Utceforp]

If we say Pluto is a planet, the other dwarf planets will have to be planets too, and then nothing works!

This^. Classifying Pluto as a planet but not Eris would break the definitions and create contradictions. Eris is estimated to be 27% larger than Pluto.

Also, if we classified Eris and the other dwarf planets as planets, what would we say? My Energetic Mum Just Served Us Nachos wouldn't work anymore.

[Wilkshire]

No, it's a dwarf planet, too erratic to be classed a real one.

[Cameroi]

No, it's a dwarf planet, too erratic to be classed a real one.

so erratic and dwarf equals not real? so that means if i eat a tomato from a dwarf tomato plant, i won't get any nourishment because it isn't real?

[The Imperial Republic of New Kyoto]

This^. Classifying Pluto as a planet but not Eris would break the definitions and create contradictions. Eris is estimated to be 27% larger than Pluto.

Also, if we classified Eris and the other dwarf planets as planets, what would we say? My Energetic Mum Just Served Us Nachos wouldn't work anymore.

Did you just kick Venus out too? (For reasons only beknownst by their lordships at the IAU...)

[Cameroi]

By referring to Pluto as a planet, you also confirm that Eris, a dwarf planet larger than Pluto is also a planet, and you also have Sedna, MakeMake, Huamea, etc.

We'd easily have 12+ planets.

Sorry darling, we'd easily have 200+- planets.
In the solar system that is, with the objects from the Kuiper Belt, I'd be a slightly bigger number.

so what the hell is wrong with having 12+, or even 200?

orbiting a sun and having sufficient mass to retain a spherical shape and an atmosphere is a logical and coherent definition of a planet. some arbitrary amount of mass or proportion of size, is not.

[Tlaceceyaya]

Sorry darling, we'd easily have 200+- planets.
In the solar system that is, with the objects from the Kuiper Belt, I'd be a slightly bigger number.

so what the hell is wrong with having 12+, or even 200?

orbiting a sun and having sufficient mass to retain a spherical shape and an atmosphere is a logical and coherent definition of a planet. some arbitrary amount of mass or proportion of size, is not.

As is having cleared its orbit.

[Utceforp]

Also, if we classified Eris and the other dwarf planets as planets, what would we say? My Very Energetic Mum Just Served Us Nachos wouldn't work anymore.

Did you just kick Venus out too? (For reasons only beknownst by their lordships at the IAU...)

Nobody likes you Venus. Go home Venus, you're drunk.

No, I just derped and forgot to add that part in. My point still stands though.

[Cameroi]

so what the hell is wrong with having 12+, or even 200?

orbiting a sun and having sufficient mass to retain a spherical shape and an atmosphere is a logical and coherent definition of a planet. some arbitrary amount of mass or proportion of size, is not.

As is having cleared its orbit.

if its orbit isn't cleared enough for it to still be there, how come it still is?