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Since it was stripped of planetary status, Pluto’s defenders have been fighting
- KineticLensman 1mo ago"How I Killed Pluto and Why It Had It Coming" - awesome title for an Astronomy book
- drxzcl 1mo agoIt’s not exactly an astronomy book. It’s more a memoir of an astronomer. But it’s funny and very well written. Also, if you have the opportunity too see @plutokiller teach planetary science or give a lecture, I can recommend you do so!
- baggy_trough 1mo agoBring back Pluto!
- drxzcl 1mo agoIt’s still there. Where it always was.
- gus_massa 1mo agoAs the article explains, if you bring back Pluto you must include Eris too, and perhaps Makemake and Haumea if you ignore is not as round as expected, and who know how many other undiscovered small object near them. (And Ceres? I like Ceres.) Anyway, 9 is not an option, you must choose 8 or 10+.
- snapcaster 1mo agono you don't. just because some nerds say it doesn't make it true. just bring back pluto and nothing else
- wolrah 1mo agoScience works on logical rules. What logical rule would you propose that allows Pluto to be a planet without also bringing in a bunch of others? If you just want to arbitrarily declare things are they way you like them to be, religion is over there.
- snapcaster 1mo ago>What logical rule would you propose that allows Pluto to be a planet without also bringing in a bunch of others? The rule would be: pluto is a planet, stay mad nerds
- amanaplanacanal 1mo agoI don't have a dog in this fight, but the real rule appears to be "that's the way I learned it in school".
- flerchin 1mo agoI'm on board with all the dwarf planets. MVEMCJSUNPHME should be easy to make a mnemonic.
- elictronic 1mo agoPluto is grandfathered in through the collective Consciousness of society. Just treat it the same way as tomatoes, which are officially fruits but no child believes that crap.
- gus_massa 1mo agoMy daughter heard that tomatoes are fruit in YouTube, and now she wants to reclassify pumpkins and half of the vegetable as fruits. Next time you go to the grocery, grab a cucumber and a watermelon and try to find the differences.
- mr_toad 1mo agoScience doesn’t care about collective consciousness. Nor does the universe.
- heyitsmedotjayb 1mo agoIt's been renamed to Planet America, thank you for your attention on this matter.
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- drxzcl 1mo ago> “One of the biggest flaws with the IAU definition is that you can have the same object in two different orbits,” says Kornfeld. “In one, it’s considered a planet, and in the other, it’s not considered a planet.” So… planet Ganymede when? Or Titan?
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- adolph 1mo agoIt seems as though Pluto's primary problem is "clearing the neighbourhood." Given Pluto's orbit travels closer and further from the sun than Neptune, does Neptune also have the neighborhood clearing problem since it has not cleared Pluto? In celestial mechanics, "clearing the neighbourhood" (or dynamical dominance) around a celestial body's orbit describes the body becoming gravitationally dominant such that there are no other bodies of comparable size other than its natural satellites or those otherwise under its gravitational influence.[0] https://en.wikipedia.org/wiki/Clearing_the_neighbourhood https://en.wikipedia.org/wiki/Clearing_the_neighbourhood
- drxzcl 1mo agoTrans-neptunian objects, including Pluto, are in orbital resonance. They owe their stable orbits to the existence of Neptune. It’s like saying Jupiter is not a planet because the Trojans exist.
- beloch 1mo ago...or like saying Earth is not a planet because NEA's share our orbit. If you have to argue that it doesn't apply to Jupiter or Earth because they are obviously planets, it implies that "clearing the neighbourhood" is a vague and not particularly useful criteria.
- drxzcl 1mo agoExcept I said nothing of the sort. I said the opposite. Jupiter, Neptune and earth in your example dominate the gravity of their orbit by locking the smaller bodies into orbital reasonances. It’s not a vague criterium. It might be an irrelevant one if you are interested in geophysics, but it’s concrete and testable.
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- hn_submit 1mo agoI'm in the same camp. I believe the classification of Pluto as a dwarf planet was arbitrary and inconsistent. I mean, it's been known as a planet for almost 80 years and suddenly we demote it? I believe someone was trying to make a name for themselves here and ignoring the history of Pluto and its discovery.
- space_fountain 1mo agoThe issue is that when we discovered Pluto we thought it was much bigger than it turned out to be. If it was as big as they thought then sure it would be a planet. As it is it isn’t even the most massive dwarf planet
- hn_submit 1mo agoThey saw a problem with the discovery of other Kuiper Belt Objects and came up with a pseudo-scientific definition to "solve" the discrepancy.
- vova_hn2 1mo ago> pseudo-scientific definition How is it pseudo-scientific?
- jerf 1mo agoOr alternatively, how would any conceivable definition not be equally "psuedo-scientific"? There isn't going to be a bright, shining line. Our own Solar System is complicated enough and if we could see out into the cosmos with equal detail the lines would get even fuzzier. Judgment calls are inevitable.
- nemomarx 1mo agoHow to keep Pluto as a planet but say larger objects than it that also orbit the sun aren't planets, is the question I guess?
- Oarch 1mo agoBack in school I learned the acronym: My Very Easy Method Just Speeds Up Naming Planets And it was so convenient! Does anyone know a good alternate now that the P is gone?
- petcat 1mo ago> Does anyone know a good alternate now that the P is gone? My Very Easy Method Just Speeds Up Naming
- kazinator 29d agoAnd fitting; since by means of a vote we messed up the definition of planet, we omit from the acronym the claim that we are naming planets.
- Aachen 1mo agoI think of them more as by properties: Mercury hasn't even an atmosphere, it's too close to the sun; Venus is a hot earth so it sits closer than us; then comes its sister planet Earth; Mars is cool by comparison and sits further away than we do. Jupiter and Saturn are harder but sit before the ice giants Uranus and Neptune, again making logical sense. Whether Jupiter or Saturn comes first, I guess there's some memorisation, with or without some sentence about it
- onraglanroad 1mo agoI just remember the 4 inner rocky planets which is pretty easy, and then the giant outer planets spell JSUN. Asteroid belt in between and the second asteroid belt (the Kuiper belt) on the outside. Then the Oort cloud surrounding the whole thing as a shield to protect the system from alien incursion.
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- adrian_b 1mo ago> “One of the biggest flaws with the IAU definition is that you can have the same object in two different orbits,” says Kornfeld. “In one, it’s considered a planet, and in the other, it’s not considered a planet.” No, there is no flaw in this, and moreover there is nothing new in this. This is how it has always been, it is not something invented recently. In the Solar System, there are 3 Mercury-sized satellites and other 3 Moon-sized satellites, besides the Moon. If they had not been in their orbits as satellites, they might have very well been planets. Therefore the old definition of "planet" also depended on the orbit of the body, not only on the size and shape of the body. Most of those satellites are bigger than Pluto. Triton, the biggest satellite of Neptune, had been in the distant past another planet with an orbit close to Pluto, but it was captured by Neptune and it has become a satellite. Otherwise it would have remained a "dwarf planet", orbiting close to Pluto. So Triton was demoted from "planet" to "satellite", by Nature, not by a human organization. The current definition of "planets" and "dwarf planets" is fine. If anything, there are too few planet classes, not too many. A more useful classification is into big planets, medium planets and small or dwarf planets, where the Solar system has 4 big planets, 4 medium planets, and a lot of small planets. The big planets, i.e. which are big enough to retain the volatile chemical elements, like hydrogen and noble gases, not only the refractory elements, have a very different chemical composition from the medium planets, and this difference will also exist in any other stellar system that has condensed from gases like those at the origin of the Solar System, with more oxygen than carbon (there exists the possibility of stellar systems with a different chemical composition than the Solar System, formed by condensing from gas mixtures with more carbon than oxygen).
- ivan_gammel 1mo agoI‘m seeing this classification for the first time, but it sounds very reasonable and feels like it should have been like that. Is it your idea or is there any story behind it?
- adrian_b 1mo agoMany people use it, but it is not something codified formally by an international organization, like in the IAU definitions of "planet" and "dwarf planet".
- jerf 1mo agoYou know, this is really just a fantastic opportunity to realize the phenomenal psychological power of "headcanon". Who cares if Pluto is or is not tagged with the word "planet" by some organization you know effectively nothing about, have no control over, has no control over you, and couldn't so much as move a pebble on the planetary body in question any time in the next 20 years, if not more? Have whatever emotional relationship you like with "Pluto" and don't wait around for others to validate it. It's fine. Nobody can stop you. I'm a bit fond of Ceres myself. Nobody can stop me. Nobody needs to approve it. Take control. Write your own headcanon.
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- autoexec 1mo agoI agree, call whatever you like whatever you want. Just don't expect schools to teach that to anyone else. We get enough of that from the folks who want to replace science class with "God did it".
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- b0rtb0rt 1mo agowho did do it?
- jsbisviewtiful 1mo agoIn case anyone was curious, the Moon is bigger than Pluto. Pluto's 2/3 the size of the Moon. If any dwarf planet should be upgraded to a planet, it's Eris. Eris's diameter is over 600km bigger than Pluto's.
- lenerdenator 1mo agoAye, but what does Pluto orbit, and what does the Moon orbit?
- vova_hn2 1mo agoPluto orbits center of combined masses of itself and Charon, which does not lie within either of them. Also, they are both tidally locked to each other, just like Moon is tidally locked to Earth.
- jsbisviewtiful 1mo agoIn order to be defined as a planet, an object needs to meet 3 criteria: - Orbits a star (Pluto does and I assume that's what you were asking about) - The object has enough mass to pull itself into a sphere (meets this criteria) - The object has enough gravity to have cleared its nearby orbit of debris and other objects Neither Pluto nor Eris qualify for a planet because of that last one and, like I mentioned, the Moon has more mass than Pluto and Eris. The Kuiper belt objects all have this issue, but my point was that dwarf planets are pretty small - especially compared to other objects around Sol. If you walked non-stop around the Moon it would take 91 days compared to Pluto's 62 days and Eris's 61 days. The designation of dwarf planet is not that big of a deal imo.
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- odyssey7 1mo agoYou’re describing the planets that are conformant to the 2006-IAU specification.
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- bryanlarsen 1mo agoThe main objection to calling Pluto a planet appears to be that if Pluto is a planet then up to about 200 other objects should also be called planets, that the list would be of unknown size and regularly changing. That's an objection? No, that's a benefit! I think it'd be awesome to be regularly discovering new planets.
- andrewflnr 1mo ago"Discovering new planets" only has the cachet it does because there are so few of them, and they are individually so significant. It would quickly lose that significance if there were hundreds of them. To be precise, it would acquire exactly the significance it actually deserves, but having diluted the meaning of "planet" as applied to the big eight in the process. We would soon want another name for the originals to compensate. We can still be reasonably excited about discovering new things in the solar system without pretending they're in the same category as Earth and Neptune.
- odyssey7 1mo agoWith or without the IAU definition, you still end up with innumerable planets. Scientists regularly claim to have found planets orbiting other stars. They do this even though they have no way to verify that their neighborhoods have been cleared. And yes, you can decide that some particular things are special. That’s why culture is a big part of this. Many people consider Pluto to be special even though they are well aware that it’s not the only one out there, and that’s why they refer to it as a planet. The idea that there would be too many planets isn’t really a problem that needed solving. Would we start classifying every dinosaur as either a T-Rex or a triceratops because otherwise there would be too many dinosaurs? It’s plainly ridiculous.
- derbOac 1mo agoThat's sort of what bothered me the most at the time. It seemed like the argument was that it was "emotional" or something to keep Pluto a planet when there might be so many of them. But I never understood why it was less "emotional" to insist that a planet be a certain size or that there should be a certain number of planets.
- Sharlin 1mo agoThis seems like the least important issue in the world to keep complaining about.
- Aachen 1mo agoDeciding the color of the bike shed is easier than making important decisions about the building it sits next to. It's a well-known phenomenon https://en.wikipedia.org/wiki/Law_of_triviality https://en.wikipedia.org/wiki/Law_of_triviality
- Planktonne 1mo agoThe actual problem here is weirdly aggressive nerds who are incapable of nuance, and insist that an astronomical classification (Pluto is not a planet by the IAU definition) should be used in non-astronomical contexts. Historically and culturally, Pluto is considered a planet. An IAU classification shouldn't be used to try and retroactively change that, because the IAU does not have control over history and culture. It's a fun fact (did you know that Pluto is not classified as a planet by astronomers?) not a diktat. Similarly, a banana is 'officially' a berry, which means that it is classified as a berry by botanists. This does not mean it is considered a berry in any other contexts. If you told someone you had made a berry crumble and it was filled with bananas, you would look strange. We have countless examples of this (often focused around food): a tomato does not belong in a fruit salad no matter what botanists say. Different terms are used with different specificity in different settings. Language and culture and [older disciplines] are not governed by the rules of [newer disciplines or bodies]. If people with 'I love space' t-shirts would stop "um actually"-ing, no one would have a problem.
- ketzu 1mo agoI wonder how happy each group would be by this solution. Planet as a scientific and non-scientific usage. Conclusively, science class would not teach Pluto as a planet (it should after all stick to the science) and English class will discuss the cultural impact of planet Pluto! Maybe write poems about the importance and impact of 9 word mnemonics? Sounds fun. My headcanon is that people would hate it so so much! I can't wait to see that as a distant observer.
- odyssey7 1mo agoThis would be a really good discussion topic in schools. People need to understand the dynamic between science and society, because that is an important part of how the world works today. Pluto is an exemplar. And also, the value of culture. It might not be a scientific result, but it still shapes our experience of the world. Pluto is beloved.
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- kazinator 1mo ago> Pluto represents the underdog ... I see what Schindler did there!
- GrumpySciGuy 1mo agoLet the experts decide same with any other field.
- animitronix 1mo agoIt's time to give it up. Nobody wants there to be 23 planets...
- tehnoslow 1mo agoThe claim that the IAU vote was procedurally invalid is interesting
- baggy_trough 1mo agoThe correct planet criteria are, IMHO: - not a star - not orbiting a planet - roundish - greater than 1000km radius That would restore Pluto to its rightful place and add Eris.
- orwin 1mo agoWhy 1000 km radius? I know that 1000k diameter might be important for cold bodies to keep their equilibrium, but what does 1000km radius give? Because honestly anybody who played stuff like KSP RSS or any space game taking place in our solar system represented at scale with adequat orbit weirdness probably told themselves "that's Pluto? Ok i get it, not a planet".
- baggy_trough 1mo agoIt's just a nice round number to use as a clear boundary.
- Aachen 1mo agoWhy not just have it be rounded under its own gravity? Collapse two rules into one. If nice round systems with clear boundaries is what you're going for
- baggy_trough 1mo agoYou still have to have some subjective number to decide how round something has to be, and it admits too many small objects.
- metalman 1mo agoPluto as one of the outer Canadian planets in the Canadian solar system, which as you now know is part of the Canadian Galaxy is realy such a trifling concern back on one of the Canadian Continents that contains Canada proper the center of Universal Canada, but since there is dissent on it's status something can be done through a referendum. go ahead,laugh, but wait till google AND wikipedia both come on board
- odyssey7 1mo agoThe problem is that the word “planet” refers both to cultural symbols — mythology, gods, archetypes, and the heavens — and to objects of scientific study. Those are different domains, and one of them is cultural heritage, and the other is irritating when it tries to infringe on the first one. There’s no need for a god complex. Stop picking and choosing which planets are real. Scientists can create their own, more precise words for things. Planets are sacred. Things that clear their orbits are not. You can’t subdue the public into giving up their gods out of difference to science — you’re just losing people.
- zzo38computer 1mo agoI think not quite, although many planets have the names of the gods. They called them planets due to their motion, so it is still called that. The use of the same word in different contexts can have different usages and different (but sometimes related) meanings. "Planet" is used differently in astrology than it is in science (astronomy); this isn't a contradiction (although, like any words, can sometimes result in confusion if you do not make the meaning clearly).
- Timon3 1mo agoWhy would a change today be such a violation of a sacred concept, when Pluto was added not even a century ago? If anything, it seems like the scientists back then had a god complex, and this would be rectifying their mistake.
- odyssey7 1mo agoScientists can do whatever they like. The problem is when they try to exert control over other scientists and members of the general public. We have both freedom of speech and freedom of association, which means the IAU has no authority to govern my own speech, and it’s irritating that so many people seem gleeful to tell me otherwise.
- Timon3 1mo agoHow is the IAU trying to exert control or asserting any authority to govern your speech? I'm really having trouble seeing how the IAUs actions are in any way unusual for this kind of scientific organization, so please be specific about the consequences you expect to suffer for not following along. And more importantly, why does the incredibly recent addition of Pluto to the list of planets not fall under scientists "try[ing] to exert control over other scientists and members of the general public"? You'd have a point if the planets were set in stone for hundreds of years, but as-is I can't follow your logic why one is okay and the other is not.
- ecliptik 1mo agoIt's dumb, but whenever I see something representing the planets, I always count them. Occasionally you come across places that still include Pluto. Most recent example I found was the Swatch MoonSwatch Collection [1], which includes the Sun, Moon, eight planets and Pluto[2]. 1. https://www.swatch.com/en-us/bioceramic-moonswatch-collection.html https://www.swatch.com/en-us/bioceramic-moonswatch-collectio... 2. https://www.swatch.com/en-us/mission-to-pluto-so33m101/SO33M101.html https://www.swatch.com/en-us/mission-to-pluto-so33m101/SO33M...
- lloda 1mo agoPluto was only discovered in the 1930s. The only cultural heritage of Pluto as a ‘planet’ is a few decades of science schoolbooks, but going by these comments you'd think it's been in the same list as Jupiter since the Babylonians.
- nephihaha 1mo agoUranus and Neptune don't have a long human heritage either. Neither appears to have been known to the Babylonians.
- DSMan195276 1mo agoYeah apparently people are getting harassed on the regular about Pluto, I'm a little confused.
- odyssey7 1mo agoUnfortunately this is both a false dichotomy fallacy and an appeal to extremes. 1. Yes, there are culturally significant things that have happened since the 1930s, including the discovery of Pluto and its designation as being a planet. In fact, in 2006 -- far more recently -- a group of people got together -- known as the IAU -- and they also performed a cultural act amongst themselves when they decided to stop calling Pluto a planet, undertaking a social process ("voting") in adopting criteria for doing so. 2. If you would rather define a planet as a wandering star that's visible to unaided humans in the night sky, I'd respect that, and I kind of like the idea. It's somewhat romantic, and it avoids the myriad issues that the article here discusses that have caused the 2006 IAU definition to start to smell bad. However, it's really none of my business. The problem comes up when you police what other people call things, not when you decide to subscribe to the IAU of your own volition.
- 5555624 1mo agoAs fare as I'm concerned, Pluto is a planet. I've got a hand-written note from Clyde Tombaugh that says so. Back in the mid-1990s, a year or two before he died, I write him asking about some astronomers who were starting to question it.
- davidguetta 1mo agoPluto is a planet.
- atmavatar 1mo agoBack in my day, we had nine planets.
- bigstrat2003 1mo agoWe still have nine planets. The IAU has no power to tell me what to classify things as.
- d--b 1mo agoHumanity's need to categorize things never ceases to amaze me. Is it Art? It's not Art! Are bananas a vegetable or a fruit? Pluto definitely is a planet! No it's not! Jesus, what a waste of energy. Are we just realizing that asteroids come in all sizes? Do we really need a sharp boundary between those we call planets and those we don't call planets? Can we consider planethood a spectrum? Like should we REALLY care if someone says there are 9 planets in the solar system, and the next person says 8? We used to say there were 3 oceans, now there are 5. In reality, there's just one big saltwater lake. Do people fight about where one ocean ends and where the next one starts? Let them call pluto a planet if they want, let them call pluto a kuiper object. We shouldn't give a fuck.
- Shuddown 1mo agoCould someone explain what the IAU means by "clearing its orbit". For example, could we consider the Earth having not "cleared its orbit" because of the Moon? The Sun attracts the Moon more strongly that Earth does, so does that mean that the Earth doesn't fit the criteria? Or does the IAU have some sort exception for moons which they've defined some place else? I'd really appreciate if someone with more knowledge could explain.
- Dylan16807 1mo ago> Could someone explain what the IAU means by "clearing its orbit". To use a different phrase from wikipedia, "orbital dominance". Other objects that stick around are either captured as satellites or forced into resonant orbits. > The Sun attracts the Moon more strongly that Earth does, so does that mean that the Earth doesn't fit the criteria? The Earth's sphere of influence goes out to about a million km, 2.5x the moon's orbit.
- jscd 1mo agoI truly don't get why people have so much reverence for Pluto. And, unlike something like "fruit," which has a botanical and culinary definition which serve different purposes, I really don't get why anyone would care about the non-scientific definition of planet. Maybe I'm just ignorant here: what's the cultural significance of some celestial object being considered a planet?
- quickthrowman 1mo agoSome people simply like to be a contrarian to the official or consensus position, Pluto itself has nothing to do with why some people are irrationally upset about its.
- pfdietz 1mo agoThe obvious solution to this issue is to destroy Pluto.(*) Many problems can be solved by application of sufficiently powerful explosives. (*) Or, possibly, eject it from the Solar System.
- tehologist 1mo agoOMG, I was taught there was 9 planets my whole life. I had no idea there is now 8 planets in the solar system. My very educated mother just sold nine....
- Syzygies 1mo agoMy favorite nonfiction book in years is "Storia della pasta in dieci piatti" by Luca Cesari. The signature chapter explores the day in 2015 when celebrity chef Carlo Cracco stated on television that a clove of garlic is an ingredient that can go into amatriciana. Cesari explores the absurdity of the resulting uproar, given the actual history of the dish. People like to make rules. Leave them be in their tree houses, unless you really like to play too. I thought it was a right of passage in high school to laugh at the French forming committees to tell peasants how to speak their native language. We haven't generalized from this example? Who gives a rat's ass whether this governing body thinks Pluto is a planet or not?
- thinkingtoilet 1mo agoThis is hardly on par in terms of stupidity, but one thing you learn from flat-earthers is that humans love disagreeing with a consensus. Nothing make a certain type of person feel smarter than disagreeing with everyone. If you say the sky is blue I'm going to say it's green because I'm so smart.
- waterheater 1mo ago>If you say the sky is blue I'm going to say it's green because I'm so smart. Flat-earthers are definitely wrong about the shape of the earth, but even they admit the sky is blue, assuming they aren't afflicted with some unfortunate variety of colorblindness. In my observations of flat-earthers, they're people who reject the consensus surrounding a particular fact because they haven't observed that fact for themselves, which doesn't make them bad people or even crazy. I do rather enjoy their attempts to measure basic scientific facts about the earth, such as when a group of flat-earthers used lasers and the ocean to measure if the earth indeed has curvature. When the evidence incontrovertibly showed the earth indeed has sufficient curvature to match the scientific consensus, many participants were quite shocked. As long as they adjusted to the consensus, or even hypothesized another theory they felt worth testing, they're not crazy, just skeptical of authority.
- aceofspades19 1mo ago
- sebbul 1mo agoClassification is a human invention… are tomatoes, cucumbers and zucchinis fruit or veggies? Non issue.
- mr_toad 1mo agoIn science, classification should have some predictive value. You should be able to predict the characteristics or behaviour of a class member based on its classification. For example if you classify something as a fruit you could predict that its seeds should be on the inside. Classifying Pluto as a planet is problematic because it lacks the behaviour and characteristics of something that formed according to theories of how planets form. If you tried to describe what a planet should look like based on the nebula hypothesis, you would not be describing Pluto. Instead it has behaviour and characteristics a lot like the many trans-Neptunian objects, so it makes more sense to classify it that way.
- kazinator 29d agoIn science, they are all fruit, but an apple is a "false fruit". In cuisine, they are vegetables.
- paxys 1mo agoThe "battle" for Pluto is an interesting case study in indoctrination. A few generations of children grew up being taught a specific fact, saw it in textbooks, learned mnemonics about it, had memorable cartoon characters named after it, and then one day they were told – with sound reasoning and plenty of scientific evidence – that they should now update their views on the topic. You would think this group of well educated, critically thinking adults would go "sure", but something fundamental in their brains just refuses to let them accept this meaningless change to their lives. Now scale this up to actual impactful topics like religion, politics, relationships, race and more and most conflicts around the world start to make sense.
- fluoridation 1mo agoThe thing is, there is no real evidence to back up the classification. The assignment between words and objects is arbitrary. A consistent definition for "planet" can be given and immediately after define the Solar System as being comprised of nine planets, with the understanding that a "planet" and a "planet of the Solar System" are similar but distinct concepts. The same is already done in biology with paraphyletic groups, with for example "reptiles" not including birds. (I say this as someone who doesn't care either way whether Pluto is a planet or not.)
- odyssey7 1mo agoYep, it’s a word. We can make more of them. We use them differently depending on the context. It’s strange that armchair scientists seem unable to understand how words work. They seem to use words fine enough? But they struggle with the abstract concept of what words are and how their meaning comes from how they are used rather than from committees. I vote we cut science funding for universities since the humanities are clearly going through difficult times.
- bigstrat2003 1mo agoIt's a definition. That is not a matter of scientific inquiry or fact, the definition is whatever people want it to be. You're belittling people for ignoring scientific evidence, but there's no scientific evidence to ignore, and cannot be.
- wpollock 1mo ago[Edited for clarity.] My issue with the IAU's definition is that the body must "orbit the Sun". I would prefer they said "star" instead, and excluded other stars (so a binary star means neither star is a planet).
- mhabe 1mo agoIf the IAU had any sense they would have made Ceres a planet instead of axing Pluto. These decisions should be made in a way that makes funding exploratory missions as easy to sell as possible. Pluto the planet wis easier to sneak through congressional budgets than Pluto the Dwarf planet. Instead of waxing poetic on the Platonic form of planet, just draw a wide line around things people want to get probes sent too without going so broad as to lose the plot. Even better would have been to give Pluto a designation like the nearest Rim Planet, implying there are so many strange Rim Worlds for us to find and explore.
- kanemcgrath 1mo agoI really think dwarf planet is a fine classification. Pluto is a planet, just a really small one. Same with Eris and the other planets in the Kuiper Belt. I don’t know why the planet count of our solar system is seemingly such a Religious number. It seems as if it is the focus of why we should define what a planet is. When I think of what a planet is, I think of a destination. Somewhere that maybe in the far future we could visit one day. I think the definition for a planet should be a body with sufficient gravity that we could reasonably orbit and land on. And we can have as many sub-classifications as we want from nano-planet to Mega-planet.
- ButlerianJihad 1mo agoOne of the best edutainment YouTubers made a video about Pluto's fate, and it made a lot of sense. The story goes that the IAU redefined "planet" to satisfy schoolteachers and keep curricula sane. That was the primary goal. So in classical times, the Sun and Moon were classical planets, on the same plane as Mercury, Venus and Jupiter and all the rest. Since the Sun and Moon were planets, they could figure in astrological reckoning in certain ways. And face it, from our observer's perspective, they have a lot in common with actual planets. In fact, the seven days of the week derive from seven planets: SUNday, MOONday, Mars, Mercury, Jupiter, Venus, and Saturn. (It helps if you list them in Spanish rather than Germanic tongues.) No, there was no EARTHday or URANUSday (thankful for small favors.) And in school growing up, many of us learned the nine scientific planets as traditionally defined. Uranus, Neptune, Pluto: all great modern discoveries to add to our pantheon. So nine is a good number. Lots of people can memorize nine and keep a set of nine in our heads. But then they discovered a tenth and an eleventh and a twelfth, and scientists began to get nervous, because something was up: there were, potentially, dozens or hundreds of "planets" to be discovered at this point, among the asteroids and among the Kuiper Belt. That's all well and good: we can name a lot of bodies out there, but school children cannot learn 3 dozen planets in a row! School teachers would never stand for it! So tedious! So there you go: the canonical list of planets needed a hard-cap and so, they lined up the 8 we had, and found all the commonalities, crystallized those into the definition, and then circumscribed the list so that it would never again grow without bound. It's not unfair to have a lot of planetoids, or dwarf planets, or asteroids and other things, just floating around. But, the good news was that third graders wouldn't need to memorize them all, and third grade teachers wouldn't need to model a solar system of 30 wonky planetary bodies. And it's that simple, really. 8 standard planets makes for good basic astronomy, good solid astrology going forward, and peaceful middle-school curriculum. Everything else is just semantics.
- jgalt212 1mo ago2 things 1. When the IAU voted to demote Pluto, it was the last day of a conference and most of the attendees had already headed home. 2. Pluto has 5 known moons. The week before the New Horizons flyby its computer crashed. This necessitated a multi day reboot. During this downtime the probe had been scheduled to be hunting for additional moons. This hunt never happened. Would Pluto still be a dwarf planet if it had 10 instead of 5 moons?
- andrewdubinsky 1mo ago"Tell them Jerry, Pluto is a planet."
- odyssey7 1mo agoFun fact: The 2006 IAU definition was explicitly scoped in a limited way so that it does not apply to anything beyond the Solar System. Planets outside the Solar System are not held to the same level of scrutiny. Over 6000 planets have been discovered outside the solar system, and none of them are required to clear their neighborhoods to be designated as planets. The IAU’s Official Working Definition of an Exoplanet can be read at: https://www.iau.org/CommissionF2/CommissionF2/Documents.aspx https://www.iau.org/CommissionF2/CommissionF2/Documents.aspx So, if someone really thinks we ought to have a universal definition for what a planet is, then they might start by having a word with the IAU.
- Timon3 1mo agoDo you have examples where data definitely shows an exoplanet that hasn't cleared the orbit? Since the accurate detection of small non-glowing objects becomes exponentially more difficult as you look further out, that seems like a perfectly reasonable explanation - far more reasonable than the evil cabal of astronomers conspiring to defeat Pluto's defendants with organized harassment campaigns...
- odyssey7 1mo agoI have not pointed any fingers at the IAU for harassing people. But do be mindful of placing words into the mouths of others.
- Timon3 1mo ago> Perhaps the IAU didn’t attempt to exert any influence over the general public and perhaps they have had nothing to do with the legions who have since been irritatingly telling people that their words are scientifically incorrect, as if the IAU is an infallible god of science and that everyone must heed the IAU at all times regardless of whether they are practicing science at the particular moment. https://news.ycombinator.com/item?id=49528442 https://news.ycombinator.com/item?id=49528442 You see where you are calling into question whether the IAU have something to do with the "legions" who you've been in other comments saying are harassing you?
- belviewreview 1mo agoI think the people who pushed to remove Pluto's status made a mistake by focusing on new discoveries. They should have told the whole story forward, starting with the thousands of years before the telescope was invented, then the gradual evolution of understanding after it was until we arrived at the idea of 9 planets plus asteroids and comets, and then the further series of discoveries since then including the Ort cloud and the Kuiper belt, and also include Newtonian physics and how the solar system was seen as stabile, but now chaotic. Then after you tell this whole larger story the whole idea of Pluto being something other than a planet makes a lot more sense to people since it was originally based on the idea the solar system has a lot fewer types of features than we know it has. But the Pluto planet demoters didn't do this. The started with the present decision and just referred back to the history in bits and pieces, and out of order. And worse than not arguing for their position as effectively as they could, they missed an opportunity to get the public interested in the whole story and how it is continuing to evolve today in various ways.