Pluto Should Be Reclassified as a Planet, Experts Say (sciencedaily.com) 194
The reason Pluto lost its planet status is not valid, according to new research from the University of Central Florida in Orlando. From a report: In 2006, the International Astronomical Union, a global group of astronomy experts, established a definition of a planet that required it to "clear" its orbit, or in other words, be the largest gravitational force in its orbit. Since Neptune's gravity influences its neighboring planet Pluto, and Pluto shares its orbit with frozen gases and objects in the Kuiper belt, that meant Pluto was out of planet status. However, in a new study published online Wednesday in the journal Icarus, UCF planetary scientist Philip Metzger, who is with the university's Florida Space Institute, reported that this standard for classifying planets is not supported in the research literature. Metzger, who is lead author on the study, reviewed scientific literature from the past 200 years and found only one publication -- from 1802 -- that used the clearing-orbit requirement to classify planets, and it was based on since-disproven reasoning. He said moons such as Saturn's Titan and Jupiter's Europa have been routinely called planets by planetary scientists since the time of Galileo.
"The IAU definition would say that the fundamental object of planetary science, the planet, is supposed to be a defined on the basis of a concept that nobody uses in their research," Metzger said. "And it would leave out the second-most complex, interesting planet in our solar system." "We now have a list of well over 100 recent examples of planetary scientists using the word planet in a way that violates the IAU definition, but they are doing it because it's functionally useful," he said. "It's a sloppy definition," Metzger said of the IAU's definition. "They didn't say what they meant by clearing their orbit. If you take that literally, then there are no planets, because no planet clears its orbit."
"The IAU definition would say that the fundamental object of planetary science, the planet, is supposed to be a defined on the basis of a concept that nobody uses in their research," Metzger said. "And it would leave out the second-most complex, interesting planet in our solar system." "We now have a list of well over 100 recent examples of planetary scientists using the word planet in a way that violates the IAU definition, but they are doing it because it's functionally useful," he said. "It's a sloppy definition," Metzger said of the IAU's definition. "They didn't say what they meant by clearing their orbit. If you take that literally, then there are no planets, because no planet clears its orbit."
And that expert's name... (Score:5, Funny)
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Jerry, from Plutionia.
ONE expert (Score:3)
In the body of the summary, the phrase "according to new research" should be rewritten to say "according to one person's opinion," since there actually is no research involved.
Re: ONE expert (Score:4, Informative)
I saw research being described. A metastudy is considered research.
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Actually, Dr Metzger (@DrPhilTill ) has been talking about this since he and a couple of others (S.Alan Stern, PI on New Horizons, @AlanStern and A.N.Other) started trying this "historical usage" tack about 6 months ago. It's a valid exercise in the history of scientific terminology, but that's not particularly relevant to the evolving ideas about how planetary systems develop.
While I have lots of respect for both @DrPhilTill and @
Clearing its orbit (Score:5, Insightful)
The redefinition of the phrase presented in the summary is silly. “Clearing its orbit” means just what it says. But then Neptune also fails that test, since it hasn’t “cleared its orbit” of Pluto - and therein lies the problem.
If scientists had meant a planet should “be the largest gravitational force in its orbit”, they would have said exactly that. The phrasing is clear, concise, and unambiguous.
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So Luna is a planet? I mean, it's the largest gravitational force in its orbit around Terra. Or do you mean the largest gravitational force in its orbit around the system's star? In our case, that's Sol. But what about intersecting orbits, or multi-star systems? What about systems where the barycenter of a prospective planet is not within a star (or other body)? What orbit are you referring to, exactly? Where's your anchor? Is it determined per body? Per system?
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Earth hasn't cleared Luna from its orbit so its not a planet.
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According to some definitions, Earth + Moon s a binary planet system.
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Luna, Terra, Sol?
I suppose you mean the Moon, the Earth, and the Sun, as we scientists call them?
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Uh, those are their names.
Sol is the name of our star and sun.
There are many stars and suns, but not all stars are suns.
No other star is Sol.
Luna is the name of our moon.
There are many moons, but the term "moon" is meaningless without specifying which moon (or, by relation which planet) you are referring to.
No other moon is Luna.
Why do you think we call it the Solar System? It is the system of the star Sol.
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"lunar", "solar" etc. are used as adjectives.
But, in professional publications, the bodies are called by their regular English names (although with the initial letter capitalized).
See this from the IAU (International Astronomical Union):
https://www.iau.org/public/the... [iau.org]
The designation of our Moon is, therefore, the Moon, with a capital M and used as a name (a proper noun). The same applies to the designation of our planet — the Earth
e.g. there's a refereed journal specifically called: "Earth, Moon, and Planets".
https://link.springer.com/jour... [springer.com]
The only place I've seen "Sol", "Luna", and "Terra" used is in science fiction!
Although I mainly work on objects beyond the Sola
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This entire shitshow sounds like when marketing gets their hands on something and decides to fuck it up for everyone else. Here's an example from cars and engines. A piston bearing isn't a piston bearing, it's a friction impact reducer. A wheel bearing is now a front hub assembly, but not always. Because some cars still use separate baring assemblies outside of the hub which contains the other components for ABS, skid control, and speed sensor. It just pisses everyone off in their specialized field.
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What the hell is a piston bearing?
Do you mean piston ring or connecting rod bearing? A gudeon / wrist pin?
Wheel bearing and hub assembly are exactly as they state.
One is literally just a bearing (made of a bearing and race, or a sealed bearing) that is pressed into the hub, and the other is the bearing already pressed into the hub as an assembly.
Wheel bearing: https://www.rockauto.com/en/catalog/honda,1997,prelude,2.2l+l4,1170201,brake+&+wheel+hub,wheel+bearing,1672
Hub assembly (bearing already in hub):
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What the hell is a piston bearing?
That's a piston bearing [tpub.com], note not bushing.
Wheel bearing and hub assembly are exactly as they state.
Nope. Those are two different pieces, your links show that. Know why? Because not all wheel bearing are already pressed into the hub, in some cases they come as separate parts because the hub assembly is another one-off manufactured component. GM/Opel/Suzuki/Toyota for example used both in various on-off model years. In the last decade it's only become standard to use a pressed bearing into a wheel hub assembly because of the integrated components and the poss
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As I stated, if you'd read, they are as their names state.
Please re-read my comment and read the whole thing.
I said wheel bears are just the bearing (sealed on piece or with a race as common in trucks). This then pressed into a hub
A hub assembly is a pre-assembled bearing and hub.
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Wheel bearings, not wheel bears.. that's what I get for quick typing on a phone
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I should also qualify I have mechanic backgrounds
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In that very journal, "Earth" is listed separately from "Planets".
It's obvious that as long as you perceive an object differently than all others of its kind, you at least instinctively exclude it from the grouping even though you rationally know otherwise.
So far, it's only science fiction where the Sun has no special distinction and thus needs an actual proper name -- as when you're standing on a planet "the sun" will refer to the local star. For today astronomers, all observations are done from our parti
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But then Neptune also fails that test, since it hasn’t “cleared its orbit” of Pluto - and therein lies the problem.
Pluto actually approaches Uranus closer than it does Neptune. Neptune did a pretty good job of getting rid of Pluto.
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There actually is no planet that has "cleaned its orbit".
How actually is that supposed to work?
All majour planets have asteroids accumulated in the two troyan points in front and behind them, how are they supposed to "clear that"?
The summary is correct. (Score:2)
You are incorrectly assuming that 'clearing it's orbit' is to be interpreted literally. It's not!
'Clearing its orbit ' doesn't mean an planet's orbit is completely devoid of any object, whether it's an asteroid hundreds of miles across. or a grain of sand. An object that is gravitational dominant in its orbit, has no other objects of comparable size in it's orbit and is not under the gravitational influence of any other objects with the exception of it's satellites has 'cleared it's orbit' and along with
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It should. Nobody is going to be living on Jupiter, but people will live on Ganymede and Ceres.
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Ceres has not enough gravity to be habitable, regardless what you build there.
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Ceres has not enough gravity to be habitable
By what measure? If a habitat in open space can be habitable, then something with 0.02g can be habitable.
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For a few month ... not for the typical life span of a human.
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but people will live on Ganymede and Ceres.
Make sure to finish your drink before the bar closes.
$250 for a new textbook I can see why they flipit (Score:2, Funny)
$250 for a new textbook I can see why they flipit
duh (Score:2, Interesting)
As people who classifying and organizing information is second nature, this is a pretty huge "duh" kind of thing.
Far from removing things from the "planet" group, the higher super-set of "planet" should be all inclusive and loosely defined itself.
Instead there should be sub-sets of different types of planets, like you know, how most of them have been for some time now.
A good naming hierarchy is your friend.
Even the name "dwarf planet" implies a sub-type of "planet" called "dwarf"
Keep splitting up groups int
Re: duh (Score:2)
Well, yeah. That's how ontologies are normally devised and how astronomers devise them for all other objects. Except here.
But this is ridiculous (Score:2)
How is historical literature relevant? (Score:5, Insightful)
We don't consider medical definitions in the context of the four humours, heck late 19th century astronomers thought space was filled with luminiferous aether [wikipedia.org] so why are their opinions on the definition of planets suddenly considered insightful.
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We don't consider medical definitions in the context of the four humours, heck late 19th century astronomers thought space was filled with luminiferous aether so why are their opinions on the definition of planets suddenly considered insightful.
Labels for many body parts and symptoms originally named by Greeks hundreds of years B.C. are still widely used.
What isn't EVER relevant is constructing arguments based on some whacked blanket appeal to age and prejudice rather than actual merit.
My personal view the IAU's behavior is simply illegitimate and I refuse to recognize it.
Domain experts are free to develop whatever specific terms they want to refer to whatever they damn well please AMONGST THEMSELVES. They are not free to take ownership of popula
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Labels for many body parts and symptoms originally named by Greeks hundreds of years B.C. are still widely used.
And they had no idea what most of it did - naming body parts only demonstrates they had eyes.
My personal view the IAU's behavior is simply illegitimate and I refuse to recognize it.
And what behaviour is that exactly? Clarifying and re-classifying as we learn more?
Domain experts are free to develop whatever specific terms they want to refer to whatever they damn well please AMONGST THEMSELVES. They are not free to take ownership of popular language used by everyone and modify popular language by decree. Certainly not by vote on the last day of an IAU meeting when many had already left involving less than a 4% of astronomers /w zero feedback, input or outreach to the general public. Bullshit to that.
Got it, I assume you also don't believe the skin is an organ because we didn't consider it to be one in the past?
Personally I don't care either way if pluto is a planet or not.
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And what behaviour is that exactly? Clarifying and re-classifying as we learn more?
This was explained specifically in the immediately following paragraph. You cited it in your response:
"Domain experts are free to develop whatever specific terms they want to refer to whatever they damn well please AMONGST THEMSELVES. They are not free to take ownership of popular language used by everyone and modify popular language by decree. Certainly not by vote on the last day of an IAU meeting when many had already left involving less than a 4% of astronomers /w zero feedback, input or outreach to th
How many planets do you want (Score:3, Interesting)
So how many planets do you want?
If we let Pluto be a planet, then our solar system will also have to start officially calling all the other minor planets, planets. i don't think that's reasonable or important. its simply not worth it. Pluto is a an object, we know its there, but it doesn't need to be on a list that includes the 8 major planets. i don't care how you categorize it, we simply cannot have a never ending list of planets to include in our definition of the solar system.
-Jeff
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So how many planets do you want?
The more the merrier!
How many moons should Jupiter have?
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... we simply cannot have a never ending list of planets to include in our definition of the solar system.
Sure we can. We just need to use the appropriate data structure to store the list.
Re:How many planets do you want (Score:5, Interesting)
Yeah, and there are too many chemical elements (118) on the Periodic Table, so what we need is a new rule that limits the number of elements to a nice, easy-for-schoolkids-to-memorize list of between 8 and 12 "major elements". I don't care how you categorize it, we simply cannot have a never ending list of elements to include in our definition of reality.
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Yeah, and there are too many chemical elements (118) on the Periodic Table, so what we need is a new rule that limits the number of elements to a nice, easy-for-schoolkids-to-memorize list of between 8 and 12 "major elements". I don't care how you categorize it, we simply cannot have a never ending list of elements to include in our definition of reality.
I know you're using that poor form of argument called sarcasm. But say, someone decided to call water an element. Would that bother you? This isn't about limiting the count, but classifying similar objects the same way. The people in favor of Pluto being a planet often say, that's how they learned it. Should new elements be denied because they hadn't been made when I was in high school? Because I did a report on the heaviest element and now it isn't any more?
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Yes, this is about classifying similar objects in similar ways. As opposed to the IAU definition that says one of two physically identical bodies would be a "planet" if it is in orbit around the Sun directly in an orbit with no other bodies, but "not a planet" if it happens to orbit a gas giant, or has a lot of other bodies in its orbit, or orbits any star other than the Sun, or just is wandering in interstellar space.
Yes, there are idiots who want Pluto to be a planet because that's the way they learned i
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In the case of elements, there are clear rules as to what distinguishes and element from something else. Although there is a recognized heaviest elem
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Yeah, and there are too many chemical elements (118) on the Periodic Table, so what we need is a new rule that limits the number of elements to a nice, easy-for-schoolkids-to-memorize list of between 8 and 12 "major elements". I don't care how you categorize it, we simply cannot have a never ending list of elements to include in our definition of reality.
Earth, Air, Fire, Water, and Aether?
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Re: How many planets do you want (Score:3)
I don't care about the number. That should be a function of how many there are. You should not choose the number of planets and then set a definition accordingly.
If a sensible, scientifically useful, definition ends up with 100 planets then there are 100 planets.
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Yeah, numbers bigger than 8 confuse me too!
Oh my god! What happened to your thumbs?
Earth too! (Score:3, Insightful)
Impacts on Earth and Jupiter clearly show they haven't "Cleared their Orbits" either.
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Also the moon is really a co-orbiting planet, so we really, seriously, haven't cleared our orbit.
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Jupiter has two huge blobs of so called Trojany (asteroids) sitting in the two langrange points 60Â in front and behind on its orbit.
I doubt it is actually possible to "get rid of them" in the sense of clearing your orbit :D
Partly Nonsensical (Score:5, Interesting)
Read the Wikipedia article on clearing the neighborhood [wikipedia.org]. It's defined well enough and people know what it means. Claiming that "If you take that literally, then there are no planets, because no planet clears its orbit." is like pointing to the requirement that a planet must be round, and saying that if you take that literally, no planet is round. Yes, no planet is 100% round, but it's possible for a planet to be close to round or not very close to round, and the same goes for clearing the neighborhood.
The research that shows that nobody used this definition in the past is probably correct. But it doesn't help. Scientists can make up new definitions.
Furthermore, while it's also true that planetary scientists call lots of things planets, the report itself admits that they also use the term for moons. Nobody else is going to start calling Pluto a planet under a definition that also includes moons.
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Scientists can make up new definitions.
And we will roundly reject them when they are arbitrary, ambiguous, or deleterious to existing definitions.
Case in point - jackasses trying to deplanet Pluto.
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And we will roundly reject them when they are arbitrary, ambiguous, or deleterious to existing definitions.
Case in point - jackasses trying to deplanet Pluto.
By "we", you must mean the set of people who failed to master Sesame Street's rudimentary "One of these things is not like the others" game.
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No, I mean people with brains.
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Since you failed at Sesame Street, it's not surprising that you continue making mistakes.
Re: Partly Nonsensical (Score:2)
The definition says rounded not round. And that is why nobody looks for round planets. However, you'd argue a snooker ball is round, right? Earth is founder by several orders of magnitude.
What a crock. (Score:3, Insightful)
A planet has more than just orbit-clearing characteristics.
Additionally, its mass should be enough to form a spheroid. Pluto looks like a goddam potato.
A planet should stay in its own orbit.
Because the orbit is elliptically challenged, Pluto is sometimes the seventh planet and sometimes ninth, making Neptune sometimes eighth and sometimes ninth. Planets gotta make up their minds.
The fucking tater-shaped object travels all the way out to the Kuiper belt.
It's gotta be a publicity stunt. I smell money somewhere in all this.
Re:What a crock. (Score:5, Informative)
Additionally, its mass should be enough to form a spheroid. Pluto looks like a goddam potato.
You may want to check that again before you say it around anyone in person. Pluto is nicely spherical. Perhaps you're thinking of Vesta?
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Oops. You are right. Vesta.
Thank you for the catch.
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It's gotta be a publicity stunt. I smell money somewhere in all this.
By that definition everything is a publicity stunt. It's a sloppy definition. I've only found one instance from 1802 that uses that definition of publicity stunt.
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Prior to the War of 1812, publicity stunts did not exist.
The first publicity stunt was performed at the Chicago World Fair when Rufus Hockersmith served "tea," that was purported to provide tannin that would aid in curing skin blemishes.
Toxicologists outed Rufus after an analysis proved that the tonic was actually brown water from Village Creek near Burkeville, Texas.
The "tea" had a side-effect of stunting people's growth immediately, and the people at the fair were publicly humiliated.
Re: What a crock. (Score:2)
Most exoplanets violate your requirements. Some of them are super Earth in size. A few are super Jupiters.
And yet you don't complain about them. Nor does the IAU.
You don't get to pick and choose when a definition applies. If an extreme eccentric super Jupiter that crosses multiple orbits and has a rotation that deforms it horribly is a planet, then neither eccentricity nor staying in orbit nor roundness can be factors.
It's that simple.
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And yet you don't complain about them.
And yet I can't SEE them.
Their existence is only visible through a gravitational lens that neither of us has.
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Some are indeed directly visible and have been imaged. Although I don't know if the Chinese have done so, their radio telescope has easily sufficient resolving power and sensitivity to look at Proxima b's reflected radiation. Things have moved on.
No explanet has been seen by gravitational lensing, as far as I know.
When SKA is complete, every explained inside 100 LY and every super Jupiter inside of about 3000 LY will be directly visible.
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For imaged planets [caltech.edu], these are usually the planet properties, typically including, at minimum, the semi-major axis and planet mass, and the stellar properties, usually, at minimum, the distance to the host star and the stellar mass.
So we don't know if, for example, they are orbit-clearing.
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Correct. We know a few are inside still-condensing accretion disks and therefore can't have. Highly eccentric, criss-crossing orbits also happen. We can't be sure of the rest.
However, this creates an amusing situation. Any planetary mass that hasn't cleared its orbit is a dwarf planet. There are therefore dwarf planets upwards of ten times the size of Jupiter.
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Expolanets? In the IAU definition, a planet must orbit the Sun. Which means any and all exoplanets, by IAU definition, aren't planets.
It is rank nonsense, and that after twelve years such an asinine definition still stands is to the clear discredit of the IAU.
He didn't look very hard (Score:2)
Seriously there was more literature out there, like the one published in 2006.
But in all seriousness what kind of a stupid basis for a new definition is that? "You can't use this new definition because it's different than the old definition". No shit Shirlock.
Because nostalgia (Score:2)
That's why!
oh boy (Score:2)
I think few people would call that a "planet". In common usage, moons orbit planets, planets orbit stars.
The only issue is that there are some other things that orbit stars: asteroids, stellar rings, etc. Among those, planets are objects large enough to have been shaped into a spheroid under gravitation.
Re: oh boy (Score:2)
Common usage includes rogue planets. Rogue planets do not orbit stars.
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No, but they used to.
A rogue planet is to a planet kind of like a dead parrot is to a parrot.
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That is perfectly true and I wish the IAU had included that in the definition.
So, I guess the first question is, we know the planetary orbits shifted dramatically when Saturn formed. It shifted Jupiter out of the inner solar system. Did Saturn or Uranus forming shift Neptune or Pluto in any way that would mean both had cleared their orbits prior to this?
Secondly, the moons of Pluto are all inside its atmosphere and are probably shattered fragments from Pluto being struck. If we track their motion backwards,
Planet! Planet! Planet. (Score:2)
Who are we to decide? (Score:5, Funny)
If Pluto identifies as a planet then I think we should respect that decision. Maybe Pluto is astronomical body fluid, one day a planet, the next day not.
Obligatory - NY Times Pluto-crisis (Score:2)
Brought to you by ThePeople's Cube [thepeoplescube.com]:
Pluto is a World (Score:3)
Blut Pluto is a world in it's own right now that we've visited it. It's a place. So is Ceres, Vesta, even P/67 Churyumov–Gerasimenko is a world now that we've been there. They are no longer points of light or blurry objects in our telescopes. I use world as a poetic term not a scientific one. I know this comment is short on details arguing against considering Pluto a planet but considering it a world.
The other reason I don't want Pluto to be re-classified as a planet is because people would lose interest in astronomy and forget about. It keeps people engaged in the debate. However, if you want to call it a planet, fine. I'll call it a world.
Expert is wrong (Score:2)
A planet should retain an atmosphere (Score:2)
Of some certain density, or at least have sufficient gravity to do so. If that means kicking Mercury out of the club along with Pluto, so be it!
This is not the simple problem people think. (Score:5, Insightful)
Any definition of planet has to be true for:
All objects universally agreed on in our solar system to be planets
All exoplanets of Earth size or larger
All rogue planets that are not brown dwarfs
All planets within accretion disks
This basically means you can't use shape, orbit or objects in proximity in your definition.
Your definition must exclude all:
Rocky asteroids
Rubble pile asteroids
Comets
Brown dwarves
Stars
Dead stars in orbit around other stars
That's not going to be easy, since a lot of characteristics are shared.
Finally, any definition must be as simple as possible and predictive. On seeing a new planetary object, given a certain perfect subset of characteristics plus the definition, we must be able to infer at least one other thing about the object. Otherwise, it's not a useful definition.
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Then when a white dwarf in a binary system dies it becomes a planet. It's a body that is no longer a star (it no longer undergoes fusion) that is orbiting a star.
It also means a planet that escapes a star stops being a planet until recaptured, despite never actually changing in and of itself.
I am fine with definitions of a system being about a system, but I'm not keen on definitions of an object being about a system. That's a scope violation.
It's also not good when classifications are not time invariant, si
Who is the "planet" label really for? (Score:2)
The classification of "planet" is mainly for the benefit of the general public. This is a pragmatic decision that helps keep knowledge of the Universe accessible and manageable for the masses. Sorry planetary scientists but your needs are secondary. Relax, you'll survive this.
We would'nt have this discussion if... (Score:2)
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Right, let's get this straightened out. Just like we did with planet "Urectum".
https://www.youtube.com/watch?... [youtube.com]
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Right, let's get this straightened out. Just like we did with planet "Urectum".
https://www.youtube.com/watch?... [youtube.com]
Urectum hell - damn near killed him.
Re:Sad (Score:5, Insightful)
Its not about emotions, it's about useful terminology. To a planetary scientist, a planet is a body that's large enough to be in hydrostatic equilibrium, which creates a fundamental distinction between two very different types of bodies. A body in equilibrium is differentiated, has been altered by fluids, has experienced geothermal heat over long time periods, etc. A body not in equlibrium is undifferentiated and - if old - comprised of the primitive relics of our solar system. To a planetary scientist, the large moons are likewise "planetary" moons, in that they're gone through the same sort of differentiating processes as planets; their position and path of motion does not change what they are.
The IAU, which is primarily astronomers and not planetary scientists, made a big mess for actual planetary scientists. Rather than creating their own new orbital classification for their needs, they took away a term in widespread use from another set of scientists. The latter have been the leading voices for overturning the IAU decision since then.
The fact that the planetary science definition is much closer to the popular definition than the IAU definition is is actually a side point. Although one worth bringing up nonetheless. New Horizons lead Alan Stern likes to bring up the "Captain Kirk Test", when discussing the popular usage of the term, as distinct from either scientific usage of the term. That is, if the Starship Enterprise was in orbit around it, and Captain Kirk said "Beam us down to that (blank)", would that word be "planet", or something else? As humans, we automatically recognize "object in space so large that its gravity has pulled it into a sphere" as a planet. To the point that we sometimes struggle when discussing science fiction when such bodies are presented as moons. Think of how many times you've heard Star Wars fans refer to the Forest Moon of Endor as a planet or whatnot.
Of course, all *this* is tangential to the fact that the IAU definition is a completely self contradictory minefield based on false premises (foremost of which is that planets actually clear their own neighborhoods - Mars's neighborhood, for example, was primarily cleaned by Jupiter, not Mars***), but that's an entirely different story....
*** No, the Stern-Levison parameter doesn't help. It's based on a current body's ability to clear asteroids, not a planetisimal's ability to clear other planetisimals. And indeed, Stern is as mentioned one of the biggest opponents of the IAU definition. Basing your argument on a guy who disagrees with it is never a good start!
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As it seems to me: the "clearing the neighbourhood" argument is obvious bullshit even to a non-astronomer like me, but it was used to get through a more reasonable distinction that has no plausible definition: the difference between a pebble and a boulder. And here, the difference is massive: Pluto is over 25 times smaller (by mass) than the lightest new-definition planet. It's also a chunk of ice rather than of rock.
You're also right about the pointless requirement that a planet needs to orbit a fusor.
Re: Sad (Score:3)
Proper classification is essential in science, as all things classed the same should behave the same at that level.
It's pointless to have models, classification or even science if groupings are arbitrary and models aren't predictive.
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I'd ideally use two naming conventions.
For the scientific name, I'd borrow from biology and computer science. Biological classifications use a complex tree to describe the ontology. In computer science, neural nets are very good at finding the different ways two populations can be linearly separated. So we end up with a tree that runs from coarsest to finest divisions.
For the common name, I think your suggestions are just fine but those specific divisions might end up not really existing. We need to find ou
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Re: Not (Score:5, Insightful)
It makes a huge difference. Basically, if you can't classify Pluto then there's no point in bothering with astronomy or planetary science since you can't predict or classify. In fact, you might as well jump off a building since it renders science and modern life futile if you cannot predict or classify. You're left only with religion.
One, and only one, designation will be useful in any predictive or functional sense. To use any other designation is the work of mystics, not planetary scientists.
What that designation is can be determined only by looking at what has actual scientific value, not what has votes in a conference.
Understood? Good.
Re: (Score:2)
Basically, if you can't classify Pluto then there's no point in bothering with astronomy or planetary science since you can't predict or classify
...? You trailed off there. If you can't classify Pluto as a planet or a non-planet, you can't predict what about it? Seems like knowing its size, chemical makeup, etc. would be way more useful than knowing its IAU classification.
Re: (Score:2)
If those follow a pattern for a certain class of objects, you can give the class a name.
If there is no class, you can't predict. Every observation is unique and devoid of meaning.
Those are your choices. Order or randomness.
Re: (Score:2)
You trailed off again there. "If there is no class, you can't predict..." ...what? Throwing around hilarious hyperboles like "devoid of meaning" and "those are your choices, order or randomness" and "you might as well jump off a building" takes the spotlight off the fact that nobody's really using the "planet" classification to predict anything specific, simply because the definition is so ad-hoc, and there's no real tweak to it that makes it significantly more useful than it is now.
Re: (Score:2)
Look, it's very simple.
A definition should have certain properties.
First, any classification is itself a hypothesis and must therefore follow all the rules governing a hypothesis. This includes the ability to predict, since a hypothesis must be falsifiable.
Second, if you contend that nothing in the observable universe can be categorized or understood by science, what else could you call it but random? Even most religions have structure and rules that science could infer. If you have no such structure, if sc
Re: (Score:2)
Wrong split. And that is why that particular split is useless.
Rather than split between two magnitudes (which is rarely helpful), you split between two categories (which is).
You can categorise between reflection, refraction and diffraction. THAT is the correct division.
You have demonstrated precisely why arbitrary classes are useless, why you must use classes that have distinct, predictive, meaning. You have shown why value-based definitions are abhorrent, why classifications should have intrinsic rather th
Re: (Score:2)
Basically, if you can't classify Pluto then there's no point in bothering with astronomy or planetary science since you can't predict or classify.
This is beyond retarded. Pluto has been classified in different ways over the last decades. Did people stop doing astronomy or planetary science in any of those periods ?
Re: WUT?! (Score:4, Interesting)
No. The eggheads didn't attend the IAU conference. Most aren't even astronomers.
This hasn't been settled because nobody agrees on the basis. The IAU doesn't want school textbooks with 22 planets in the solar system, the some reason for reclassifying. Planetary scientists don't give a crap about the books and want a definition with actual meaning.
Re: Sinbad was wrong (Score:2)
Occasionally, people are wrong. It happens. Scientists are scientists because they're willing to be wrong. It's the nature of a hypothesis that you're going to be wrong most of the time. Science is not about being right, it's about figuring out why something was wrong and not doing it again, becoming less wrong with time.
If you want Truth, theology is down the hall.