Is Pluto a planet?

[Entropian]

Is Pluto a planet?  According to the IAU, no, but what do you think? 

[sevenperforce]

It is a dwarf planet just like all the other Solar System bodies which are large enough to be gravitationally rounded but are not large enough to clear their orbit around the sun.

Edited October 12, 2020 by sevenperforce

[Nuke]

its a dwarf planet, so yea. i view dwarf planets as a subset to planets. it even has the word planet in its classification. 

Edited October 12, 2020 by Nuke

[magnemoe]

Its an dwarf planet, problem is we have no idea how many Pluto sized kuiper belt objects we find down the line, it might be hundred so keeping it an planet might not work. Its an reason why Ceres got kicked out of the list back in the 19 century. 

[NFUN]

34 minutes ago, Nuke said:

its a dwarf planet, so yea. i view dwarf planets as a subset to planets. it even has the word planet in its classification. 

so minor planets are planets?

[kerbiloid]

Like I said in another thread,

2 hours ago, kerbiloid said:

Quote

Public reception to the IAU decision was mixed. A resolution introduced in the California State Assembly facetiously called the IAU decision a "scientific heresy".^[64] The New Mexico House of Representatives passed a resolution in honor of Tombaugh, a longtime resident of that state, that declared that Pluto will always be considered a planet while in New Mexican skies and that March 13, 2007, was Pluto Planet Day.^[65][66] The Illinois Senate passed a similar resolution in 2009, on the basis that Clyde Tombaugh, the discoverer of Pluto, was born in Illinois. The resolution asserted that Pluto was "unfairly downgraded to a 'dwarf' planet" by the IAU."^[67] Some members of the public have also rejected the change, citing the disagreement within the scientific community on the issue, or for sentimental reasons, maintaining that they have always known Pluto as a planet and will continue to do so regardless of the IAU decision.^[68]

According to wiki, Pluto is probably still a planet when it's passing above IL or NM (better discuss this with your lawyer).

So, real patriots of Pluto should take an ephemeris calculator and make a calender of these moments.

 

[Flying dutchman]

I voted yes and i know that it's not the scientific consensis but i feel bad for poor pluto. Maybe we can give it the title of "honorary planet" ?

Edited October 12, 2020 by Flying dutchman

[Kernel Kraken]

No, not a planet. But I feel like we should choose a kinder term than "Dwarf Planet", as Pluto deserves a majestic classification like the king of the Dead he is.

[RCgothic]

No, Pluto is a dwarf planet, or planetoid.

That said, I think the *has cleared its orbit* criteria is rubbish.  If you transported Pluto to the inner solar system it would be a planet.

That doesn't seem like a good definition to me.

[Entropian]

7 minutes ago, RCgothic said:

I think the *has cleared its orbit* criteria is rubbish.

I agree.  It's a bad definition, but it's still a dwarf planet.

[Deddly]

I always felt that the "dwarf planet" definition was pretty contrived, to be honest. It feels like they just had to find a way to make the solar system have fewer planets, so they arbitrarily invented some new classification rules. 

So yeah, for me, not only pluto but also all the other objects orbiting earth that are large enough for gravity to form them into a sphere are planets. 

Edited October 13, 2020 by Deddly
Late night posting...

[Scotius]

There are many plutinos who rival (or exceed) Pluto's size or mass. Are you advocating to classify all of them as planets? Aside of a bunch of hung up on it people, Pluto doesn't stand out from the crowd much. Well, Charon is somewhat unique as far as moons go - but that's about it.

Just... let it go, guys.

[Superfluous J]

The technical term "planet" has a definition. You don't have to like it but as a technical term it must be precisely defined and used to be of any use to the people who use it.

Call Pluto what you want. Call the Moon a planet if you want, or the Sun. It was good enough for ancient people it should be good enough for us.

[Entropian]

52 minutes ago, Deddly said:

make Earth the solar system have fewer planets,

Fixed it for you. 

[kerbiloid]

It's a Charon's moon, as their barycenter is outside them both.

[cubinator]

Nobody should feel bad for Pluto, nor any other dwarf planet. We're not declassifying a person or a dog here. Creating a new classification to better describe new discoveries is perfectly scientific. The difference between a dwarf planet and a planet is arbitrary, but it doesn't make Pluto, Eris, Sedna, Makemake, Haumea, Orcus, or Arrokoth any less of a world. Pluto has not been made less interesting. The beautiful water mountains and nitrogen plains have not been changed by a council on the distant Earth. Pluto is a world. Planet is fine, dwarf planet is fine, they are synonyms of 'world' to an extent. This is not a problem.

[Nuke]

8 hours ago, NFUN said:

so minor planets are planets?

just an opinion, not sure thats what the aiu indented though. 

 

8 hours ago, magnemoe said:

Its an dwarf planet, problem is we have no idea how many Pluto sized kuiper belt objects we find down the line, it might be hundred so keeping it an planet might not work. Its an reason why Ceres got kicked out of the list back in the 19 century. 

yea i kind of think the needed to define everything as planets, and then categorize those better. dwarf planets get one, you might have another for giant planets and terrestrial planets.

8 hours ago, RCgothic said:

No, Pluto is a dwarf planet, or planetoid.

That said, I think the *has cleared its orbit* criteria is rubbish.  If you transported Pluto to the inner solar system it would be a planet.

That doesn't seem like a good definition to me.

i think id reserve the term planetoid for large things that haven't quite made it to hydrostatic equilibrium. 

[Nuke]

8 hours ago, RCgothic said:

No, Pluto is a dwarf planet, or planetoid.

That said, I think the *has cleared its orbit* criteria is rubbish.  If you transported Pluto to the inner solar system it would be a planet.

That doesn't seem like a good definition to me.

idk ive seen the case made (and the math for) gravitational dominance in the solar system. major planets or giant planets should be the major concentrations of mass in the solar system (other than stellar objects) which ultimately guide the motion of the rest of the solar system. and at the other end things that dont have much influence at all with planets actual in the middle. 

[kerbiloid]

1. The "planet" is a term of ancient times, when just 7 celestial bodies were known.
Now all celestial bodies should be "a category 1 (, 2, 3, ...) hierarchical node of Solar System attraction graph", without all that uncertain mumbling about "having cleared its path".

1a. We should realize that basically there are no "celestial bodies". We call so balls of matter gathered around local gravity maximums.
Yes, created by their own mass, but the planet is not something atomic itself, it's just a heap of atoms attracted to the local gravitational maximum.
So, we should not blind our eyes with vision, but first see the abstract and invisible attraction maximums, and only then see the heaps of matter sticked around them.
This automatically devalues all those "planet"-"nonplanet" archaic terms.

2. Someone having a ready-to-use statistics program at hands, should run cluster analyzis of the celestial bodies (say, by mass and radius), to split them in clusters, to see if the Pluto closer to the "planets" or to "asteroids", and to split the polyphyletic "asteroid" group (including the moons) into several clusters. Because it's just silly to distinguish Mercury and Io, but to join a 500 km rock ball and a 1 km snowball.

3. How can Pluto be a dwarf planet, when we haven't seen any dwarf there? Did they hide? It's ours.

Edited October 13, 2020 by kerbiloid

[Superfluous J]

So what people don't like is that Pluto was "demoted" whatever that means. I didn't realize it was in the military.

So the problem is that "Planet" is a badge of honor. Again for some reason that I don't quite understand. We just need to think of a better name than "Dwarf Planet" then so it's not like Pluto's being demoted, but just getting reclassified so it is better described. You know, like the actual reason for this whole thing.

How about Omega Worlds? That sounds pretty cool and they're the last worlds out there so it fits.

[K^2]

Pluto definitely can't be a planet or we'll have like a dozen more we'll have to add.

Moon, on the other hand, totally a planet. It's silly that we count it as Earth's satellite, when Sun pulls on it a lot stronger than Earth does. Moon orbits the Sun and happens to share the orbit with Earth. So we should bring the count back to 9, with Earth-Moon system counted as a binary.

I know, I know, some people might complain that Moon not being a moon would get confusing. But if Moon is reclassified as a planet, it would need to be promptly renamed after a Roman deity, and honestly, the only sensible choice is to call it Luna. So that should resolve the confusion. Well, in English. Other languages will have to find their own workarounds.

P.S. I have one final argument. If we say that Moon/Luna is a planet, humanity is technically an interplanetary civilization.

Edited October 13, 2020 by K^2

[Okhin]

Well, iirc, the reason why Moon is a moon is because the rotation's barycentre of Moon and Earth around each other is still inside Earth (not by much, but still). And yes, maybe that definition is tailor made to consider the Moon as a satellite of Earth, but it works :p

[kerbiloid]

1 hour ago, Superfluous J said:

We just need to think of a better name than "Dwarf Planet"

A warrant planet.

Edited October 13, 2020 by kerbiloid

[Deddly]

9 hours ago, Scotius said:

There are many plutinos who rival (or exceed) Pluto's size or mass. Are you advocating to classify all of them as planets? Aside of a bunch of hung up on it people, Pluto doesn't stand out from the crowd much. Well, Charon is somewhat unique as far as moons go - but that's about it.

Just... let it go, guys.

Yeah I would classify all the others as planets too. Why not? 

1 hour ago, K^2 said:

Moon orbits the Sun and happens to share the orbit with Earth.

I believe that makes Earth a dwarf planet

1 hour ago, K^2 said:

Pluto definitely can't be a planet or we'll have like a dozen more we'll have to add.

That's what I could never understand. What is the problem with having dozens of planets? 

[kerbiloid]

The "planet" is a rank, like the "officer", to distinguish the noble ones from various others.

Whether a lieutenant is under command of a captain, or a general, or another lieutenant, this doesn't make him stop being an officer.

The fact than an army has many thousands of lieutenants, doesn't make all of them stop being officers.

***

Also, we should distinguish "rank" and "post" of the celestial body.
It can be an "officer" by mass, but at 3rd level of hierarchy by post. This still doesn't mean that it's not a planet.

***

So, a military rank system looks the most proper.

Private body:
A piece of rock with no significant self-gravitation.

2nd class Private body: a 10 m stone.
1st class Private body: a ~1 km stone.

Sergeant body:
A more-or-less ball of matter having its own self-gravitation.
If divide it, it becomes a single body again.

(Various classes) Sergeant body, like asteroids, comets, and icy moons.

Warrant planet.
Not really a planet, but wannabe.

2nd class Warrant planet. Plutinos, Enceladus.
1st class Warrant planet. Pluto, Ceres.

Also.
4th class Warrant planet. The largest piece of rock between the group of privates.
3rd class Warrant planet. The largest piece of rock between the group of sergeants.

Officer (planet).

Typically, over 0.5*10²² kg, i.e. Moon-sized and bigger.

2nd class Lieutenant planet. Moon, Io.
1st class Lieutenant planet. Mercury, Ganymede, Titan, Triton.

Captain planet, Mars.
Major planet. (And the pun is intended). Earth, Venus.
Colonel planet. Super-Earth/Super-Venus.

General (planet).

A planet, enough heavy to hold the hydrogen atmosphere.
Also usually they have a company of lesser bodies.

Brigadier General planet. Uranus, Neptune.
Major General planet. Saturm
Lieutenant General planet Jupiter.
Colonel General planet. Super-Jupiters, maybe brown dwarves

Full General.
A star.

********

So, in the Solar System we have:

Full General Sun,

1st Lt. Mercury (under its direct command)

Major Venus

Major Earth with 2nd Lt Moon.

Capt. Mars with two sergeants.

A belt of privates, sergeants, with several warrants.

Lt.Gen. Jupiter (Sun's deputy) with 1st Lt Ganymede, 2nd Lt Callisto, Europa, Io, and dozens of sergeants and privates.
Also two Trojan companies of privates and sergeants with their own 3rd class Warrants.

Mr.Gen Saturn with 1st Lt Titan and others.

Br.Gen. Uranus with others.

Br.Gen Neptune with 1st Lt Triton and others.

A Kuiper belt of warrants. 1st class Warrants Pluto, Eris, and Sedna are the main ones.

An Oort cloud of privates, sometimes being recruited.

***

So,
Pluto is 1st class Warrant planet,
Moon is 2nd class Lieutenant planet (under Major Earth's commandment).

And everything gets simple and clear.