'Yes, Pluto Is a Planet' (sfgate.com) 301
schwit1 quotes a Washington Post perspective piece by the authors of a new book about Pluto:
The process for redefining planet was deeply flawed and widely criticized even by those who accepted the outcome. At the 2006 IAU conference, which was held in Prague, the few scientists remaining at the very end of the week-long meeting (less than 4 percent of the world's astronomers and even a smaller percentage of the world's planetary scientists) ratified a hastily drawn definition that contains obvious flaws. For one thing, it defines a planet as an object orbiting around our sun -- thereby disqualifying the planets around other stars, ignoring the exoplanet revolution, and decreeing that essentially all the planets in the universe are not, in fact, planets.
Even within our solar system, the IAU scientists defined "planet" in a strange way, declaring that if an orbiting world has "cleared its zone," or thrown its weight around enough to eject all other nearby objects, it is a planet. Otherwise it is not. This criterion is imprecise and leaves many borderline cases, but what's worse is that they chose a definition that discounts the actual physical properties of a potential planet, electing instead to define "planet" in terms of the other objects that are -- or are not -- orbiting nearby. This leads to many bizarre and absurd conclusions. For example, it would mean that Earth was not a planet for its first 500 million years of history, because it orbited among a swarm of debris until that time, and also that if you took Earth today and moved it somewhere else, say out to the asteroid belt, it would cease being a planet.
To add insult to injury, they amended their convoluted definition with the vindictive and linguistically paradoxical statement that "a dwarf planet is not a planet." This seemingly served no purpose but to satisfy those motivated by a desire -- for whatever reason -- to ensure that Pluto was "demoted" by the new definition. By and large, astronomers ignore the new definition of "planet" every time they discuss all of the exciting discoveries of planets orbiting other stars.
Even within our solar system, the IAU scientists defined "planet" in a strange way, declaring that if an orbiting world has "cleared its zone," or thrown its weight around enough to eject all other nearby objects, it is a planet. Otherwise it is not. This criterion is imprecise and leaves many borderline cases, but what's worse is that they chose a definition that discounts the actual physical properties of a potential planet, electing instead to define "planet" in terms of the other objects that are -- or are not -- orbiting nearby. This leads to many bizarre and absurd conclusions. For example, it would mean that Earth was not a planet for its first 500 million years of history, because it orbited among a swarm of debris until that time, and also that if you took Earth today and moved it somewhere else, say out to the asteroid belt, it would cease being a planet.
To add insult to injury, they amended their convoluted definition with the vindictive and linguistically paradoxical statement that "a dwarf planet is not a planet." This seemingly served no purpose but to satisfy those motivated by a desire -- for whatever reason -- to ensure that Pluto was "demoted" by the new definition. By and large, astronomers ignore the new definition of "planet" every time they discuss all of the exciting discoveries of planets orbiting other stars.
So... (Score:5, Informative)
If Pluto is a planet, aren't a large number of other bodies in the solar system also planets? [washingtonpost.com]
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Yes. At the very least, any reasonable definition that excludes the "cleared the neighborhood" requirement would mean that Ceres would go back to planet status (currently dwarf planet, previously asteroid), as would Eris, and possibly the other dwarf planets.
Personally, I am of the opinion that "planet" is correctly defined, except for the "orbiting Sol" part, which should be revised to "orbiting a star" (with "star" defined as "non-singularity body capable of fusing hydrogen", which excludes deuterium-burn
Re: So... (Score:2)
That would mean a planet ejected be the star becomes a brown dwarf star (as per current definition) and turns back into a planet on recapture.
Dunno about you, but I'm a little unhappy with this planet-star duality depending on where it is.
Rule number one in science is that things should be space-invariant and time-invariant. This is clearly neither.
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Is there any supportable theory of planetary or stellar evolution in which a planet sized object could be "ejected by a star" ? Even stars such as neutron stars, struck by other neutron stars, would eject matter so unstable without the stellar mass of the neutron star that it would explode into gas during its departure from either host star. While larger atoms such as gold have been detected after neutron star collisions, It's unclear that anything like a planet could form from the ejecta.
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I think you're misunderstanding ejected. 2 planets pass by close enough that their orbits are perturbed, one makes a close pass by its star and gets accelerated enough to leave the system.
Some of the leading theories of our solar systems early days have an extra gas giant or two that get ejected from the solar system.
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That could be what was meant. If so, I'd like to clarify the language. I'm not sure what phrase would be more clear. There were some older theories of planetary formation that included extrusions happening from stellar passby's, but those have been almost entirely discarded.
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Well the over poster did continue to say recapture, which to me implies gravitational ejection.
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I personally find any "scientific" taxonomy that requires the pre-existence of a theory to be... absurd.
The empirical method involves observations, then the development of a taxonomy based on repeatable observations, and only then the development of a theories. If you decide on your theory first, you do not get Darwin's origin of species, nor do you get the periodic table of the elements. What you get is what happens when the Church persecutes Galileo because his discoveries cast doubt on accepted theory a
That's not what Galileo got in trouble for (Score:2)
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I personally find any "scientific" taxonomy that requires the pre-existence of a theory to be... absurd.
To the contrary: Every taxonomy needs a founding theory. Terms and words only have a meaning within a theory. That's why for instance "ring" has completely different meanings in Mathematics, in Telephony and in Wedding ceremony.
It doesn't make sense to discuss the meaning of words without first agreeing on a common theory the words are part of.
To go back into Astronomy: In the Inka terminology, there are also constellations, but they are completely different from the Mediterran ones we use. Even the wor
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Rule number one in science is that things should be space-invariant and time-invariant. This is clearly neither.
Huh? There are plenty of things that change and are called something else. Off the top of my head...
Water->Ice->Steam
Meteor->Meteorite
Lava->Igneous rock
Star->Black Hole
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Apparently Jupiter isn't big enough to fuse hydrogen
It needs to be 75 times more massive to fuse hydrogen and 13 times to fuse deuterium like a brown dwarf
Yes, that was actually the point (Score:5, Interesting)
The whole reason for "demoting" Pluto had nothing to do with Pluto itself. It had to do with Eris [wikipedia.org]. When Eris was discovered, it appeared to be (because of its albedo) larger than Pluto. It is, in fact, more massive tham Pluto is though slightly smaller. Because of its size, the discoverer was making a strong case for having it accepted as the solar system's 10th planet. While this gave NASA a huge ole woody, because they were counting the dollar signs of how a newly discovered actual planet would spur public opinion for exploration, it caused significant consternation at the IAU. That's actually understating things. A few members of the IAU were quite literally horrified at the prospect. They were looking at the fact Michael Brown's team had discovered scads of Trans-Neptunian-Objects, that there very well could be half a dozen or more additional ones the size of Pluto/Eris, and they were quite happy with the set of planets we already had, thank-you-very-much. There was a certain historical congruency to it and no upstart finding a TNO that happened to be as large as Pluto was going to get his name listed in the same breath as such nobility as William Herschel. So they decided that in the end, that since they really couldn't call Eris a planet if Pluto was a planet, they did what they thought was the lesser evil. They preserved the sanctity of the rest of the solar system by demoting Pluto.
Of course the definition has holes and is not even self-consistent. The whole purpose of it was to demote Pluto and all other similar objects and to ensure that it was worded such that no other TNO could ever be labelled a planet, by nature of being out in the area where nothing is "cleared".
What people need to ask themselves is this: does the fact that the IAU had its collective head up its ass tell me what I consider to be a planet? The answer for me personally is a big whopping no. And when it comes up in conversation, usually after I name all 9 traditional planets (sometimes adding Eris) and get "corrected" that, hey, don't I know Pluto isn't a planet any more, that's when I let the poor smarty-pants have it with both barrels. Not really their fault, but anyone toeing the IAU party line and not willing to think for themselves deserves to get it.
The IAU isn't an official body with any authority other than what they have taken on themselves. And if they are going to let historical politics cloud scientific thinking, they certainly aren't going to speak for me. I'd like to see some textbook publishers take a stand too.
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First of all your question assumes facts not in evidence. You are stating as a fact within your question that that Pluto has few similarities to the other eight planets. While it's difficult to nail down Pluto's geology precisely, best evidence suggests that Pluto has a rocky/metalic core, a probably liquid mantle, and a solid crust. How much other differentiation there are between layers (an outer/inner mantle, outer/inner core) is pure guesswork right now, but as it stands it has quite similar enough g
Comment removed (Score:4, Interesting)
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...was going to get his name listed in the same breath as such nobility as William Herschel.
Not to mention a farm boy named Clyde.
Re:Yes, that was actually the point (Score:5, Insightful)
The thing is, if you don't accept the IAU's authority, then whose authority are you going to accept? Textbook publishers? They're one notch above those scammers who sell you the "right" to name a star.
The IAU's membership is over 12,000 professional astronomers [iau.org], which as best as I can tell is a pretty good percentage of the people with careers in astronomy. The next largest professional group is the American Astronomical Society [wikipedia.org], with about 7,000 members all in the Americas. Their stance on the issue is decidedly neutral [aas.org].
In the end, the definition of a planet is merely semantics. What's important is that whatever definition you decide to use is functional, allowing generalized statements to be made easily without running afoul of the terminology. In that respect, I don't have a problem with the division between "planet" and "trans-Neptunian object" and dwarf planet [wikipedia.org]. They are different enough and the terms selected for them, although not perfect, are definitive enough to make statements and issue papers about them without tripping over the semantics.
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The thing is, if you don't accept the IAU's authority, then whose authority are you going to accept? Textbook publishers? They're one notch above those scammers who sell you the "right" to name a star. The IAU's membership is over 12,000 professional astronomers [iau.org], which as best as I can tell is a pretty good percentage of the people with careers in astronomy. The next largest professional group is the American Astronomical Society [wikipedia.org], with about 7,000 members all in the Americas. Their stance on the issue is decidedly neutral [aas.org]. In the end, the definition of a planet is merely semantics. What's important is that whatever definition you decide to use is functional, allowing generalized statements to be made easily without running afoul of the terminology. In that respect, I don't have a problem with the division between "planet" and "trans-Neptunian object" and dwarf planet [wikipedia.org]. They are different enough and the terms selected for them, although not perfect, are definitive enough to make statements and issue papers about them without tripping over the semantics.
And yet only 424 [space.com] of them were allowed to vote on the matter, on the last day of a conference.
I can't find the source, but I read somewhere that a previous measure, agreed to by most, would have preserved Pluto as a planet. Thinking the matter settled, most of the delegation went to play golf or drink beer, and a small minority pushed their agenda through.
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This! This got me upset. I'm not a member of the IAU, but an amateur who has a degree in physics and has taken astronomy, astrophysics and planetary geology courses at the graduate level.
Astronomers play politics.... this one got nasty. Then NASA got involved, then celebrities and it snowballed. I still answer 9 when asked how many planets there are by a kid when he looks through my telescope. Most people I know do too... including professors of astronomy... but there is a small minority who loves beating y
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The real problem was that Pluto was ever considered a planet, given the history of Ceres. It is just not big enough compared to the rest and its orbit is quite different then the rest.
At the time of its discovery there were arguments about it and one of the reasons it was accepted as a planet was due to being an iceball, it looked bigger (brighter) then it actually is. Originally comparable to Mercury in size, the estimates kept shrinking its size until really it is more comparable to an asteroid.
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Isn't that a bit like saying, if your penis is small enough, we should call it a clitoris?
*shrug* (Score:5, Insightful)
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So the IAU is basically a religious organization intent on preserving the sanctity of their belief system? Oh wait, that is just one faction within the IAU. The IAU's problem is really that it had not developed a meaningful concept of "quorum" in time to prevent it from being subverted by a group of reactionary radicals.
Re:Yes, that was actually the point (Score:4, Interesting)
The whole reason for "demoting" Pluto had nothing to do with Pluto itself. It had to do with Eris [wikipedia.org]....
Everything you say is true, but it gets much, much worse.
They concocted this contrived definition of "planet" not long before we started finding lots more planets, thousands of them.
The IAU needs to sit down with all the exo-planet astronomers, and planetologists (like geologists, but not restricted to Earth), and think this through from the beginning, and come up with consistent, science-based classifications, and let the chips fall where they may - not use a pre-determined "correct" number of planets for the Solar System.
Of course the very term "planet" is of ancient origin and referred to those permanent naked eye lights in the sky that weren't stars. There were only the original set until William Herschel discovered Uranus (well, Earth too - after Copernicus). When asteroids were first discovered, they were planets too until astronomers realized they were dozens of them, make that hundreds of them, make that thousands of them. So the term never had a firm scientific definition.
I think a more complex classification system is called for myself. It is true that Pluto and Eris are a new class of body - Kuiper Belt Objects, just as asteroids were and are, but that doesn't mean they can't also be planets. Now that we know of some 4,500 confirmed or candidate planets (which will expand to tens of thousands in a decade or so) it is ridiculous to use those ancient six plus two planets as the standard to define what the term means.
Re: So... (Score:3)
No.
Pluto has many properties (structure being one) that Ceres and most KBOs do not have.
Second, should it matter? Once you have a scientific distinction between an asteroid and a planet, you destroy utterly the value of planetary science if you then contrive to select only that Sara which fits a preconceived notion of how many planets a solar system should have.
Only the planetary science should matter. School kids can have a cutoff point and ignore everything byond, same as they do in all other sciences. Th
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Pluto has many properties (structure being one) that Ceres and most KBOs do not have.
How so? Being more icy? Being in a less circular orbit? Or just discovered by an American?
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try the Greek god of the underworld.
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Dead language neatpicking: Hades Pluton (Score:5, Informative)
Hades is the Greek god of the underworld. Pluto is the Roman version.
And in old greek, Plouton is one of Hades' epithets [wikipedia.org] - i.e.: adjectives often used together with His name to describe Him. (Just like Zeus Himself is usually "all-seeing" or the "storm gatherer", etc.)
It means "the rich / the rich-giver", because Hades is the god of the underworld and earth itself (as opposed to Posseidon who's got the seas and Zeus who's in charge of the sky), and that's where most of mines are and on what crops grow. (Might also have been because, except for heros, most mortals - both good and bad ones - end up in Hades' realm - different sections of the underworld serve as both hell *and* heaven, unlike in christian mythology - so He ends up with the most follower).
Over time, this has shifted to his euphemistical name (the thing mortals use to name him as to not anger Him) He became known "The Rich / The Rich Giver". (Just like in christian mythology, Satan is called often "the devil" instead of by his name).
And then again, over time this became used as His official name. That's what the Romans eventually picked-up in Latin.
Fun fact, the Latin "Jupiter" (in nominative case) has a similar construction : it's the contraction of "Zeus + pater" ("the father" - obviously once you look at the genealogy of most of the Greeko-Roman pantheon). But when declined in other cases, only the name is kept, e.g.: Jovis (genetive case).
So for some period of time "Pluto" is also what the Greel go of the underworld was called,
and even for some period of time it was His actual name.
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Just like in christian mythology, Satan is called often "the devil" instead of by his name
"Satan" isn't a name either, it's a regular noun in Hebrew, usually translated as "adversary" or "accuser". In the books of the Prophets (I don't remember offhand that it's anywhere in the Torah), the Hebrew is always "Ha-satan", "the accuser". It's just an angel that tells God how horrible humans are, playing the role of prosecutor in a trial.
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Definitely a dog philosopher. For every Voltaire there has to be a Kant.
But surely a Dwarf Planet is a Planet, just as a Dwarf Poodle is a Dog, and a Dwarf Human is a Human.
And yet, it is also still true that a random rock that was first distant rock somebody spotted isn't the same thing as a planet. Unless you love it so much that you're anthropomorphisizing it; then it is definitely still a Planet. So Dwarf Planets should feel like a real planet, even though they're not listed together with the other plan
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Reminds me of a comment as reported in No Laughing Matter by Joseph Heller. They had a group of men who would go out and eat dinner together periodically. Someone asked how come some other person wasn't invited seeing as he was short like the rest of them. The response was, he was too short.
Speaking of their dinner club, they had a rule about wives: it was okay for you to bring your wife, it is not okay for me to bring mine.
Related in that book is the Guillain-Barre syndrome that Joseph Heller contracted (n
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So the answer to the question "How many planets in our solar system?" is "What year are we talking about?"
When I was at school, it was 9
When my first child started school, it's 8
Now by the time my second child is at school is could be different again.
And we're all talking about the same set of objects orbiting the sun.
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It wouldn't be so bad if the number kept getting higher as more planets are discovered
What about Neptune (Score:5, Insightful)
Re:What about Neptune (Score:5, Informative)
Re:What about Neptune (Score:5, Informative)
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Pluto and it's moons are a pretty significant set of objects, and they cross Neptunes orbit
Pluto does not cross Neptune's orbit. Pluto's orbital perigee is within the radius of Neptune's orbit, but it is inclined by 17 degrees, so they are nowhere near each other. The minimum distance is 17 AU or about 1.6 Billion miles.
Pluto is in a 2:3 resonance with Neptune, so in that sense Neptune has "cleared" it.
Pluto actually gets closer to Uranus (11 AU) than it gets to Neptune.
so does that mean Neptune is no longer a planet since it sure as heck hasn't "cleared it's zone" ?
Then there are no planets, since comets pass through all of their orbits. Zone clearing means non-transients.
Re: What about Neptune (Score:2)
According to QI, Earth has tens of thousands of non-transient objects in its path.
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According to QI, Earth has tens of thousands of non-transient objects in its path.
What is "QI"?
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Re: What about Neptune (Score:3)
You can either have a valid definition and see what that gets you, or you can have a contrived definition arranged to fit a preconceived fact.
I do not encourage being insensibly drawn to fitting facts to theories.
Should we define a particle specifically to exclude electrons? Would that be useful or useless?
Who cares how large things are? Where is that a useful property to measure?
The only properties that matter are the properties that are invariant in a category and linearly separate themselves from another
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Reality is what it is, it is not a democracy and it doesn't give a shit whether you like it or not.
Nothing to add... munches popcorn... just thought it should be repeated.
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I think we should pick the definition that is the most useful. The definitions are for our benefit after all.
So if including Pluto in the planet category makes the planet category too broad (less descriptive), then it might be better to place it in the planetoid category instead. There will always be things at the margins that don't fit into either or fit into both. Maybe there are enough of these that another category becomes useful to define, maybe not.
To take an example from Math: is 1 a prime number? It
Who knows (Score:2)
Maybe they were trying to uncover A.I. spies?
I mean this is pretty ridiculous. They say "a dwarf planet is not a planet" and yet they affirm it is a planet by saying so. I mean, the first part does but then they say it's not one. That's the same as trying to convice me that TRUE equals FALSE while I perfaafkly knwaaop tiiss'stt ialllogiccccal+_(%$#@NO CARRIER
Re: Who knows (Score:2)
Incorrect. Ontologically, a dwarf planet is subcategory of planet. It is a subset, not a distinct class.
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Language is a bit more complicated then that. Is a dwarf tree a tree or shrub? The horticultural books I've read would classify the dwarf tree as a shrub but it is all a grey area with a tree being defined as bigger then a shrub, sometimes the number of stems mattering and sometimes not and what exactly is the cutoff when it comes to size?
Oh dear god, this again? (Score:5, Interesting)
Seriously, this again? Categories by nature have fuzzy boundaries. We'll have trouble telling how best to categorize the edge cases. What matters is what categories are most useful for understanding things. If the experts in an area decide to categorize something one way then let them.
To add insult to injury, they amended their convoluted definition with the vindictive and linguistically paradoxical statement that "a dwarf planet is not a planet." This seemingly served no purpose but to satisfy those motivated by a desire -- for whatever reason -- to ensure that Pluto was "demoted" by the new definition.
If I'm following this argument correctly, they are arguing that it is "linguistically paradoxical" to have something of the form "[adjective] x" to not also be in the category labeled "x". But we do this all the time. For example, in math a "skew field" is not necessarily a field https://en.wikipedia.org/wiki/Division_ring [wikipedia.org], and one can come up with many other examples in STEM fields. This is a natural thing that we do all the time. And the specific reason in this case that dwarf planets were not planets was to avoid then making Eris and Ceres and a a whole bunch of other objects also planets.
I'm fascinated that with everything else going on the world, serious people apparently think that arguing over what we call a planet or not is an important issue.
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Re: Oh dear god, this again? (Score:2)
More examples...
A red panda isn't a panda
A red dwarf isn't a dwarf
A fake Gucci handbag isn't a Gucci handbag
Solution: Pluto "identifies" as a planet. (Score:4, Funny)
It's pretty simple. If Pluto identifies as a planet, then it is one. All of this classification by scientists is just an attempt to create a privileged, sexist, and racist system that discriminates against small planetoids.
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Hey, don't expect society to conform to your delusion!
if you want to play planetary dress up, feel free. but if you were born a planet, then you're a planet.. and no amount of mental gymnastics will change that.
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OK. I just snorted wine out my nose. Thanks, guys, for my laugh of the day.
Settled (Score:3)
Politician == Scientist (Score:2)
It seems that 40, 50 years politicians were different.
Not since.
This might be the 13th sign of the apocalypse.
The bakers dozen of failures.
There's a rather important misunderstanding there (Score:3)
The reason that they think the IAU's definition of a planet is ambiguous is because they have the definition wrong. A planet does not have to completely clear its neighborhood of all other objects (the earth would not qualify if that were the case, since it shares its orbit with Luna, its moon). What makes it a planet is when it has cleared the neighborhood of all similarly sized objects.
So yes, Earth would not be a planet if it shared an orbit with a planet like mars or venus, and would be considered either a moon or possibly even an asteroid if it shared an orbit with Jupiter or Saturn, depend on whether it was gravitationally captured by the gas giant or not.
Re: There's a rather important misunderstanding th (Score:2)
The moon is large enough that the Earth and moon are considered a binary planet.
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Re: There's a rather important misunderstanding t (Score:2)
Which was indeed the case 250 million years ago. So the moon was a planet in the relatively recent past. Which means the Earth did not clear its orbit, the moon did.
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Which was indeed the case 250 million years ago. So the moon was a planet in the relatively recent past. Which means the Earth did not clear its orbit, the moon did.
Huh? What are you talking about? The Moon formed closer to the Earth and is slowly moving away. 250 million years ago it was somewhat closer and in a few billion years it may become a double planet.
Besides by your definition, Charon is also a planet.
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Even if what you're saying is true, it doesn't help your argument.
In 5 billion years the Sun will be a Red Giant. Does that mean we have to call it one right now?
Is it possible, perhaps, that the Universe is dynamic and not static?
Obligatory Rick and Morty reference! (Score:2)
https://www.youtube.com/watch?... [youtube.com]
No, Pluto is not a planet (Score:2)
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It depends [wikipedia.org]. It moves around so sometimes it's inside the Sun and sometimes it's not. It depends on how the planets are oriented relative to one another in their orbit.
Reminds me of T-Rex (Score:2)
and the idiot who went around claiming that T-Rex was a scavenger and could not hunt anything. He was a professor of something or another.
All I hear is... (Score:2)
Wah, wah, wah
It orbits the Sun and has a name (Score:2)
It is "far out", orbits the Sun, has a name.
PLUTO
is good enough - who cares about legalities when there are no lawyers out there?
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"I was big enough for your mom" -- Pluto (Score:2)
Best Pluto joke IMHO
As long as there's still only 49 states (Score:2)
100+ Planets? (Score:2)
Ethan Siegal at Starts With A Bang (makes the point that https://www.forbes.com/sites/s... [forbes.com]) makes the point that what is a planet should be considered in light of what we know about solar system evolution. According to that perspective, it does not appear that Pluto is a planet. If Pluto is a planet, then there are over 100 of them.
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Besides, since when does the number of planets have to be limited? If it's round, made of regular matter and not a star, then does its location really matter?
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Cleared its zone? (Score:2)
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view from a linguist (Score:2)
Speaking as a linguist, this whole discussion on the planethood of Pluto is just silly. Pluto is still the same icy body it always was, what earthly (pardon the pun) difference does it make whether the word "planet" is defined to include it or exclude it? I just don't understand why anyone cares.
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The reason that some people care is because when they talk about what "planets" are, it makes a difference if it some small number of large things, or a large number of small things.
Also, some of them are visible at night and it is useful to have a word that means those things, and not every little icy body out there.
Words sometimes have value, as hard as that might be to believe.
Breaking news!!!!!! (Score:2)
In other breaking news!!!!! water is wet, and the sky is blue.
Still Not a Planet, but it is a World Now (Score:2)
People profiting from Pluto say Pluto is important (Score:2)
"Yes, Pluto Is a Planet" say people selling their new book about Pluto. And they're conveniently re-igniting the controversy at the time of publication. That seems to be the whole story. Wake me up when the IAU changes the definition again. That's likely to happen when they can form a consensus on extra-solar planets but it's unlikely to reverse the demotion of Pluto.
Reinstate the asteroid planets! (Score:2)
For decades, Pallas, Juno, Vesta, Ceres, Astraea, Hebe, Iris, Flora, Metis, Hygiea, Parthenope, Victoria, Egeria, Irene and Eunomia were officially classified as planets. Until a new planet definition was widely accepted in 1854. And once more, the book authors were not part of the process. Therefore, this needs to be rewound, and the planetary status voted publicly upon on Facebook!
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I understand that Pluto prefers the term "Gravitationally Different" to the term "Dwarf"
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I understand that Pluto prefers the term "Gravitationally Different" to the term "Dwarf"
Exactly. It's perfeckly acceptable to refer to Pluto as a G.D. Planet.
Re: Pluto is a swarf planet ! (Score:3)
I don't believe in scientific notation designed to limit a group to X. Either the definition is based on sound science or it is crap.
Pluto is structurally utterly unlike Ceres or any KBO, therefore it is not in the same category as those.
Pluto is structurally the same as Earth and Mars, therefore that is the category it belongs in.
Reality is not a popularity contest, I do not give a flying who thinks Pluto is what, it is structurally the same as a planet and is structurally distinct from anything not a plan
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So you're saying the gas giants aren't planets? Same with the ice giants? And various large satellites are planets?
Besides I think you might find that Ceres is more like a rocky planet then an iceball like Pluto.
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First of all, most planets (and former planets) were discovered before the US even existed. Most can be seen from Earth with the naked eye. So congratulations, other countries, you looked up!
Secondly, there are 2 kinds of countries on Earth. Those that use the metric system, and those that put a person on the Moon... and landed on Mars... and sent probes to Mercury...
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Re: What a stupid article (Score:2)
Your solution to #1 doesn't solve rogue planets.
Your definitions still don't take into consideration the need by scientists for definitions that categorise in ways useful to planetary scientists.
They're not interested in whether the planet count is single digit in a given number base.
They care that if you plot the properties of all the objects in the solar system and apply the categorisations, all of the properties and models group perfectly within those categories and that you can falsify a prediction.
They
Re: Thank God this has been decided (Score:2)
It is if you're a planetary scientist. If you don't know what is a planet and what isn't, you can't model either.
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Doing astronomy public outreach I deal with a lot of people who are angry about the Pluto situation. It's possible that you are the angriest of them all. Are you okay?
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You can't contradict the poster that was on the wall during my childhood! Change is anti-science!
ROFLCOPTER