“Pluto-Killer” Sets Sights on Neptune


The confessed (and remorseless) “Pluto Killer” Mike Brown has turned his gaze – and the 10-meter telescope at the Keck Observatory in Hawaii – on Neptune, our solar system’s furthest “official” planet. But no worries for Neptune – Mike isn’t after its planetary status… he’s taken some beautiful infrared images instead!

Normally only visible as a featureless blue speck in telescopes, Brown’s image of Neptune — along with its largest moon Triton —  shows the icy gas giant in infrared light, glowing bright red and orange.

Neptune and Triton in infrared. Credit: Mike Brown/CalTech.

Brown’s initial intention was not just to get some pretty pictures of planets. The target of the imaging mission was Triton and to learn more about the placement of its methane, nitrogen and seasonal frosts, and this sort of research required infrared imaging. Of course, Neptune turned out to be quite photogenic itself.

“The big difference is doing the imaging in the infrared where methane absorbs most of the photons,” said Brown. “So the bright places are high clouds where the sunlight reflects off of them before it had a chance to pass through much of the atmosphere. Dark is clear atmosphere full of methane absorption.

“I just thought it was so spectacular that I should post it.”

No argument here, Mike!

Neptune, now officially the outermost planet in our solar system, is the fourth largest planet and boasts the highest wind speeds yet discovered — 1,250 mph winds scream around its frigid skies! Like the other gas giants Neptune has a system of rings, although nowhere near as extravagant as Saturn’s. It has 13 known moons, of which Triton is the largest.

With its retrograde orbit, Triton is believed to be a captured Kuiper Belt Object now in orbit around Neptune. Kuiper Belt Objects are Mike Brown’s specialty, as he is the astronomer most well-known for beginning the whole process that got Pluto demoted from the official planet list back in 2006.

Read more on Skymania.com here.


Jason Major is a graphic designer, photo enthusiast and space blogger. Visit his website Lights in the Dark and follow him on Twitter @JPMajor or on Facebook for the most up-to-date astronomy awesomeness!

119 Replies to ““Pluto-Killer” Sets Sights on Neptune”

  1. Neptune is NOT “officially the outermost planet of our solar system”; the planet definition by four percent of the IAU is no more “official” than is the alternative geophysical planet definition, in which dwarf planets are a third subclass of planets in addition to terrestrials and jovians. These pictures of Neptune are beautiful, but I urge you not to play into Brown’s whole “plutokiller” scenario, as not only did he not “kill” planet Pluto; he is also far from the only specialist in Kuiper Belt Objects and the outer solar system. The fact that five years later, the IAU definition is being questioned more and more and accepted less and less shows that Brown, who happens to not even be an IAU member, is far from the only voice in this debate. Kuiper Belt specialists Dr. Alan Stern, Dr. David Weintraub, Dr. Ken Croswell, Dr. Stephen Maran; Dr. Mark Sykes; Dr. Hal Weaver; Dr. Marc Buie; Dr. David Grinspoon, and writer Alan Boyle all oppose Brown’s position in favor of a geophysical planet definition that does not require an object to gravitationally dominate its orbit to be considered a planet. Brown may have no remorse, but his attempt at “kiling” Pluto failed. As another astronomer who specializes in Kuiper Belt Objects and the outer solar system, I urge you to discuss this issue in a more fair and balanced manner.

    1. Laurel:
      As you know I respect your opinion and unflagging position as a Pluto-planet supporter, but until I hear that the IAU and astronomical community as a whole have decided to “reinstate” Pluto as a planet – versus dwarf planet – then I have no choice at this time but to call Neptune the outermost official planet. It may be a case of semantic dispute, but it is what it is.

      Since the rest of the article is about Brown’s recent images of Neptune, his role in the whole Pluto issue and any claims he may or may not have made elsewhere are besides the point.

      1. You always have a choice, and this article could be written equally well without the “plutokiller” reference, instead, focusing on Brown’s discovery of Eris, which re-ignited a controversy that continues to this day. In the book I’m writing, I go into explanation of how the controversy over Pluto’s status dates all the way back to its discovery in 1930. The controversy did not start with Eris’s discovery. Also, given current divisions in the astronomical community, I don’t think anyone can be said to speak for that community as a whole–definitely not four percent of the IAU, most of whom are not planetary scientists but other types of astronomers, whose decision was opposed formally by an equal number of astronomers. Pluto’s reinstatement may very well end up coming through the formation of a new planetary science organization, something that has been talked about for several years now. In short, I would just like to see more acknowledgement of the ongoing controversy than description of this as a done deal.

      2. It seems like he is gonna win. No matter what definitions you come up with, it just seems not very important to whore Pluto. For the sake of simplicity. It’s just very simple to have 4 terrestrials and 4 jovians and the rest bagged into dwarfs and asteroids…or even dust. 😀

        So, maybe it’s better to stop this nostalgic, conservative and political cry.

      3. It has to do with what is right. If your son was framed for murder and went to prison, would it be nostalgic and conservative if you tried to get him freed? The 2006 deplanetization of Pluto was a farce, and the more I have learned about it, the more unjust it becomes. Earth has two asteroids in its orbit. According to the IAU, Earth should not be a planet, either.

      4. I refuse to go into comparisons, they are distracting and often false.

        Well, what is right. Obviously, it’s complicated and there are a lot of parameters to base its status on. So you can choose your preferred parameters.

        He killed it naturally with simplicity look at things. You can basically throw the science away in this case. You can decide what do you feel like as a human because it is aesthetic to you. He had the power and opportunity.

        Of course, this is until some serious arguments come to overthrown it, but so far the opposition seems unnatural and they are pushing the nostalgy without a reason.

        Earth could still be a planet. You just have to add “except the first 8 traditional planets” or “that it doesn’t hold true for big objects”.

        It might end up like with “what is a galaxy” and people will vote. Also, maybe we have to wait for other planetary systems, lots of exoplanets are tilted.

      5. I agree with you and with Christopher Marlowe, who once said, “Comparisons are odious.” My aversion to the deplanetization of Pluto may have an element of nostalgia, but I have done my homework and the decision was seriously flawed. In fact, I saw the session of the 2006 Prague General Assembly online and witnessed the Executive Committee ram-rod the Resolution through using shameless, raw abuse of power, actually cutting off pro-Pluto speakers in mid-sentence. The IAU should be ashamed of itself.

      6. It may be true, but I think it was a great marketing strategy for astronomy. Lots of people discussed it. It was a good decision based on current knowledge. At the end it might come back as a planet with a new evidence.

      7. “He killed it naturally with simplicity look at things. You can basically throw the science away in this case. You can decide what do you feel like as a human because it is aesthetic to you. He had the power and opportunity.”

        Please explain what you mean by “he killed it naturally” and why you feel it’s okay to “throw away the science” when in another post you referred to Brown’s “killing Pluto as a scientific decision based on the objects around it. Which one is it, scientific or not? Trying to artificially create “simplicity” by blurring the distinction between tiny shapeless rocks or bits of ice shaped only by their chemical bonds on the one hand and complex objects rounded by their own gravity, with geology and weather, on the other hand, is simply bad science. We cannot make the universe “simple” just because we would like it to be that way.

        And what’s this “he had the power and the opportunity?” The power is with the data, not with any person or group of people. You make this sound like a presidential election. The opposition has presented serious arguments that have nothing to do with nostalgia, but you refuse to answer them, instead repeating the same nonsense that our view is based on sentiment. At least wait for the new data we get about Pluto from New Horizons in 2015.

        You are correct about exoplanet systems, many of which have giant planets in orbits far more eccentric than Pluto’s, planets that formed the way stars do rather than the way planets do, planets orbiting their stars backwards, and even two planets sharing the same orbit. The IAU definition excludes exoplanets, which is another reason it makes no sense. We cannot have one planet definition for our solar system and a separate one or none for all others.

        The question of “what is a galaxy” has in fact been raised, as there is no clear demarcation line between small dwarf galaxies and large globular or open star clusters. This time, astronomers are reluctant to hold a vote, given how poorly they did with the planet definition.

        I prefer to describe our solar system the way Alan Boyle does in his book “The Case For Pluto.” Regarding the number of planets, he says we have four (terrestrials) plus four (jovians) plus more (dwarf planets).”

      8. Naturally, because KBOs happened and Pluto wasn’t clearly like a planet. You are not natural, because you are crying and being off-topic.

        It was based on science, but he could throw it away for a moment (or years or decades), because it was unclear and complicated, obviously we need more data, but still a good decision. You know, it’s simple now and we can decide in the future if we want to have 100, 50, 9 or just 8 planets. Plus, he made a nice marketing for astronomy. He showed that things are happening. Now, you are writting Pluto book and we will see if you’re gonna be as successful as him.

        It’s not artificially simple, 8 planets are scientifically clear and then he threw it away. It’s not continuous, it’s discrete.

        LOL, obviously it happened, so not only data have the power. 😀 Be scientific, please. 🙂 Don’t fight the reality. It can be political, we can politically decide what we like about nature or not and then we can name it however we like.

        I don’t refuse to listen to your arguments. So tell me what are your strongest ones. Hopefully, it’s a new evidence, not what was known in 2006.

        Well, we don’t know a lot about other star systems so it makes sense to me so far. We can decide on the current knowledge. If we find a lot of for example 3rd exoplanets like Pluto and 7 other will be clear, then it might change. But still we could ditch them because they wouldn’t be big enough. Or we could find lots of typical objects like Pluto as the last significant objects in exosystems and decide to name them planets.

        Yeah, dwarfs. If it stays like that, a lot of people won’t take them as planets. They are just smaller and a lot of them. They just won’t bother. You have to politically win it and punish little kids with learning about the outermost dwarf planet. 😀 The kids of the future will be able to learn 300 objects in 300 seconds. :p Also, do people bother with jovian or terrestrial??? You see, that’s why I’m talking about simplicity.

      9. Okay, I get that the comment about “punishing kids with 300 planets” is a joke. However, memorization is not important for learning. We don’t ask kids to memorize the names of all the rivers or mountains on Earth or even the names of Jupiter’s 63 moons. The idea is for kids to learn the main characteristics distinguishing the different types of planets. Many find it exciting to learn that there is such a wide variety of planets in such a vast universe.

        I am not “crying,” or off topic, and I hope that comment was also a joke. I am presenting legitimate scientific arguments in favor of classifying dwarf planets as a third subcategory of planets.

        I do not believe in oversimplifying things for convenience; that shortchanges kids by dumbing down the curriculum. We already know there are billions of planets in the universe. That is part of the real paradigm shift we’re undergoing, which is from 9 known planets to billions, with our solar system alone containing as many as 100 planets. Of course, dwarf planets in exoplanet systems will be the last to be found because they are the smallest and hardest to detect.

        I don’t know what you mean by comments like “don’t fight the reality.” What I am doing is fighting the idea that one interpretation of the reality in our solar system somehow takes precedence over another equally legitimate interpretation. This isn’t about winning and losing or about power but about presenting an accurate representation of what is out there. Everything in nature is a continuum, not an either/or. Just look at the extent and detail of the Herzsprung-Russell diagram for stars.

        Here are my scientific reasons for classing Pluto and all dwarf planets as a subclass of planets:

        A geophysical planet definition, based on the physics of the objects in question is actually the most simple. We know a planet when we see it; planets are round. They are round because their gravity squeezes them into a round shape. When this happens to objects, the objects become significantly more complex than the vast majority of tiny asteroids and Kuiper Belt Objects, which are shaped only by their chemical bonds.

        We define stars by a very similar method. To be a star, an object has to be large enough and massive enough for hydrogen fusion to take place in its core, making it self-luminous. Attaining this threshhold is a matter of geophysics, just like attaining the threshhold for hydrostatic equilibrium is.

        Objects like Pluto and Ceres compositionally are small planets. Many are geologically differentiated into core, mantle, and crust, just like Earth. This happens only when an object is large enough for the heavier elements to sink to the core. These bodies have geological processes; for example, Pluto may very well have cryo-volcanism. Ceres and Pluto may have subsurface oceans. Some have atmospheres and weather. Pluto is the only known solar system body other than Earth to also have nitrogen in its atmosphere. Pluto-Charon is the only planetary system other than Earth to have been formed via a giant impact. Dwarf planets may be located in belts of much smaller objects, but in and of themselves, they are far more like planets and have features none of those objects have.

        The latest findings on Pluto indicate the following: Pluto’s lower atmosphere contains methane gas, as revealed in March 2009 by ESO’s Very Large Telescope. This lower atmosphere is significantly warmer than Pluto’s surface, where the average temperature is –180 Celsius. Unlike Earth, Pluto has an “upside down” atmosphere where temperatures increase at higher levels by 3-15 degrees Celsius per kilometer.

        Pluto might harbor a subsurface ocean that could host microbial life and could also drive a weak magnetic field. Pluto’s largest moon, Charon, may also host a subsurface ocean and shows evidence of cryovolcanism. Again, all of these are features of planets.

        Earth is actually much more like Pluto than like Jupiter. Jupiter has no solid surface and has a composition like that of the Sun, mostly hydrogen and helium. Its moons formed with it, not via collision with another object. How then does it make sense to put Earth and Jupiter in the same category but claim Pluto is “too different?”

        The IAU definition is inherently biased against objects further from their parent stars because those objects have larger orbits to “clear.” Astronomer Hal Levison, who supports the IAU definition, has done the calculations and admits that if Earth were in Pluto’s orbit, it would not “clear” that orbit of tiny Kuiper Belt Objects either. A definition that takes the same object and makes it a planet in one location and not a planet in another is inherently flawed.

        As to arguments that Pluto formed differently than the other planets, the latest exoplanet data shows that astronomers know a lot less about planet formation than they previously thought.

        Marketing is completely separate from science. A book can be very successful but have little scientific value, as can be seen from the many 2012 books that are popular. There are a host of other books recently published about Pluto, and all have sold quite well, as this is a topic of interest to a wide range of people.

      10. Not really a joke, one day kids might be super smart. So, you don’t find the idea of learning about the outermost dwarf planet bizzare? If it’s not gonna be a planet, kids might still learn about 10 most interesting dwarf planets or proto-planets.

        I’m not joking. You refuse politics as a part of this world. Science is not everything. Some people will just rip your ass appart. You can have argumets, but they don’t seem strong enough. You have to rank them, which one are the most important or what weight do they have. You’ll have to win it politically. Lots of people will be against the 3rd type of a planet.

        1. argument, geophysical, might be round, 1 point for Pluto, but also for Earth and Jupiter
        2. Pluto is small, -1 point for Pluto, E and J are not, so 1 point for them
        3. core mantle crust, everyone 1 point except maybe J, Juno mission will tell us more about how it’s inside
        4. cryovolcanism and subsurface oceans, ??? earth doesn’t have cryo or suboceans as far as I know, E has volcans and J nothing at all, I don’t know what to make of this argument, it’s more like Enceladus properties
        5. nitrogen, lol, is that a serious argument? That’s like grasping at straws.
        6. a giant impact formed, who cares? Mercury or Venus wasn’t. What’s the point?
        7. they are in belts, -1 for them! E and J are not in Belts, +1 for them
        8. cryovolcanism again, so which of the 8 planets have cryovolcanism?
        9. “Earth is actually much more like Pluto than like Jupiter.” That deserves deeper and complicated analysis. You posted only 2 arguments! And then you have to compare these arguments with others objects possibly making these arguments irrelevant.
        10. “How then does it make sense to put Earth and Jupiter in the same category” LOL.
        – argument a. they are precious, there are only 4 terrestrial planets and 4 jovian objects compared to x dwarfs, moons and KBOS. +1 points for E and J, -1 for Pluto
        – argument b. they don’t cross into orbits of other planets. + points for E and J, -1 for Pluto, it goes inside Neptune’s orbit.
        – argument c. they are not in belts or clouds
        – argument d. they are not as eccentric and tilted +1 E and J, -1 Pluto
        11. clearing an orbit, you migh be right, but that argument therefore is not important. It doesn’t work for Pluto either. But, I’m not surprised that Pluto lost again. 😀

        You see? That’s how you get your ass ripped apart.

      11. The last time Pluto was in a match, it won, showing the Universe that it is larger than Eris, and now has four moons, not just three. The days of Pluto losing “points” due to the corruption of the IAU’s Executive Committee are long past.

      12. You can’t have it both ways. First, you imply arguments must be based on science; then you say we have to include politics as well. This simply makes no sense.

        I am not arguing that Earth and Jupiter aren’t planets. What am I arguing is that there are more than two classes of planets. Cryovolcanism, subsurface oceans, and presence of nitrogen in the atmosphere all are important because they illustrate Pluto is a complex object, one much more akin to planets than to shapeless asteroids. This does not mean that to be a planet, all objects must have cryovolcanism to be considered planets.

        I have already stated rejection of the argument that just because an object orbits in a belt of other objects, it cannot be considered a planet. If it is in hydrostatic equilibrium, it is a planet. If it does not gravitationally dominate its orbit, it is of the dwarf planet subcategory.

        As for orbit crossing, again, we have found quite a few examples of this in exoplanet systems where both planets involved are giants more massive than Jupiter.

        Pluto has not “lost” anything. It does not serve the discussion well to treat this as some sort of score-keeping exercise.

      13. You can. He did it. It makes sense, it’s a reality. After a new evidence we can decide what to do and then you can search again. I think it will be a long time till you can beat my arguments, well if ever…

        So you rejected it. I didn’t. 😀 What a beatiful world.

        It seems like exoplanets could change everything, but so far it’s an open argument. Such systems might not be stable for a long period of time.

        Well, Pluto is losing so far. Lol, score keeping exercise? Then, how do you summarize gathered scientific knowledge? How do you you decide? You pick only couple arguments you like and then ignore everything else? Or you just study and wait forever?

        So, you totally wouldn’t use politics if you found a new evidence? Let’s say you’ll find it in 2056, you won’t vote because you don’t like politics?

        Isn’t it scientific if I have more arguments?

      14. The punishment is not just to kids, it is to all of Mankind who, since 1930, have known and loved Pluto for what it is, the farthest, most mysterious planet of our Solar System. Even Mike Brown’s daughter loves Pluto and has been punished by the irrational, political move by the IAU. What do you think about the fact that an IAU member was actually threatened with the loss of his career if he would not to vote for Pluto’s demotion? Is that science? If you watch the session of the 2006 General Assembly in Prague, as I have done, you will see an abuse of power by the Executive Committee as they ram-rod through the rancid resolution, cutting off Pluto huggers in mid-sentence, et cetera. The IAU is afraid on online voting for its members, because the Executive Committee can only intimidate so many of its members and it would be harder to ram-rod.

      15. Pluto is larger than Eris, haven’t you heard the news? The official paper should be out soon by Bruno Sicardy of the Paris Observatory, but prelininary data suggests such.

      16. Because of history? Nostalgy that people have? Because it might be closest to being a planet? I don’t know, we will see. It wouldn’t be such a controversy if it wasn’t somehow special. You could do a great marketing with Pluto covering the whole bunch of similar objects.

      17. If it was a joke, then why does he call Pluto lovers liars? He is a classic narcissist. Why does he pretend to be the sole discoverer of Eris? Is that a joke, too? You are being an apologist. Let him say it is a joke.

      18. It’s a joke that has gone a bit too far, especially with journalists constantly repeating it. I would rather have people learn about the discovery of Eris.

    2. the planet definition by four percent of the IAU is no more “official” than is the alternative geophysical planet definition,

      Of course it is the official definition by fiat and praxis, IAU is the International Astronomical Union, and it has become the internationally accepted definition outside science. Geophysics is the physics of the Earth.

      What more can we wish for here?

      Also, it was an IAU open vote decision, so it is 100 % IAU and 100 % support. Actually many years of discussion led up to it.

      Of course individual astronomers may have personal opinions. But it is incorrect to claim ” four percent of the IAU” is behind it.

      And it is really unsavory to make a democratic vote out as a minority decision, by definition it is always decided and supported by the majority.

      1. The vote was held on the last day of the 2006 General Assembly without proper vetting or notice. It was a classic ram-rod job. If Earth was in Pluto’s orbit, it, too, would not be a planet. The 2006 deplanetization of Pluto was an exercise in raw power that had nothing to do with science and, in fact, one man who was there, was threatened in order to vote for deplanetization and said so publically. Stop being an apologist for the IAU. Are you on their payroll?

      2. One man there was “threatened”? How? Did the IAU threaten to send the boys ’round to break the legs of his telescope’s tripod?!

      3. He was a graduate student who was told that if he didn’t come to Prague and specifically vote against Pluto, there would be “consequences” for his academic career. In other words, he would be blackballed from getting a job in a university astronomy department. Politics unfortunately are alive and well in academia. If people have to resort to intimidation to get their way, even they know their science is on shaky ground.

      4. So, the next thing you’ll claim is that the “I” in I.A.U. is for “Illuminati”, eh?

      5. No, none of that. No 2012 stuff either. All I can say is, this happened, and I have to respect this person’s desire to for privacy. From our correspondence, it is very clear he did not make any of this up.

      6. I know for a fact that 100 percent of the IAU membership does not support this decision, as I have spoken personally to many IAU members about it. Only four percent voted, meaning 96 percent did not. No absentee voting was allowed, so anyone not in the room on that last day of the conference had absolutely no say in the matter, including Dr. Alan Stern, who was busy taking his daughter to college. Additionally, the resolution was put on the floor of the General Assembly in violation of its own bylaws, which state that a resolution has to first be vetted by the proper IAU committee before being put to a General Assembly vote. This was not done. And of the 424 (out of 10,000 IAU members), only 333 voted against the umbrella resolution that would have made dwarf planets a subclass of planets. Hundreds of professional astronomers rejected the definition in a formal petition and continue to do so. Many planetary scientists are not even IAU members. Shouldn’t they have a say in defining a planet rather than IAU members whose fields are areas other than planetary science? Other than the vote of 424 on 8/24/06, there is NO data indicating the widespread support you claim the decision has.

        Science is not decided by fiat, and I am troubled to hear this justification, as it is an appeal to authority, which is a logical fallacy. An authoritative body can decide the sky is green, but that doesn’t make it any less blue. This issue has been debated since 1930 and is not about facts so much as about interpretation of facts. Putting it to a vote was a poor choice to begin with. Time and data are what determine whether ideas rise or fall, not a vote by a closed body. That is dogma, not science.

        Geophysics may originally have been the study of the Earth, but now, it has been expanded to refer to planetary science. “Geophysicists” are those who specialize in the geology, weather, and composition of planets, a relatively new subfield of astronomy. What more can we wish for? How about recognition that this is an ongoing debate, and that it cannot be ended by decree?

      7. “Science is not decided by fiat”, you said, and that is entirely true. But is the naming of planetary bodies science? Is it something that can be verified and proven false? No. So it is to be decided, not to be proven. You can discuss about it till the cows come home, but eventually a decision must be made.
        By whom? I have no outspoken opinion on that, but I think it would be really hard to find and organize a larger community than the IAU to decide upon this (save perhaps for the UN General Assembly). And as the decision is controversial, it is not so difficult to find IAU members who do not agree with the definition that was adopted.

      8. There is a simple answer here. The IAU could have brought together its Working Groups on Planetary Nomenclature and on Small Bodies Nomenclature and had them both come up with a name. Instead, they created this debacle for no reason other than to determine which of their committees should name the object (Eris). No one is disputing the name or even the designation of dwarf planet. What is being disputed is the notion that dwarf planets are not planets at all. At this point, even many IAU members feel the proceedings of 2006 should never have happened. So what if things are open-ended for a while? And if anyone at all is to make a decision, it should be those who study planets, not those who study other areas of astronomy and never deal with planets at all.

    3. Oh for the love of Zod, give it up! classifications are only words, so who freaking cares!? Besides, with larger objects than Pluto out there, what, do you want a solar system in 50 years with 100 planets? They’re only thinking towards a simpler future per classifying. There are SO many more important things to get upset over, really…………………….

      1. What objects larger than Pluto are out there? So far, not a single one. Eris is marginally smaller than Pluto although it is more massive. And yes, I do want recognition of a solar system with 100 planets if that is what we have. Making things simpler for the sake of convenience when doing so blurs a distinction as important as that between asteroids and small planets is not something desirable. Memorization isn’t important either; what is is having kids learn the characteristics of the different types of planets. Look at how we classify stars, via the Herzsprung-Russell Diagram. It is an entire spectrum that encompasses a huge range of objects with tremendous variety while recognizing that all fall under the broad classification of “stars” because they fuse either hydrogen or deuterium and are therefore self-luminous. Why not do the same with planets, to encompass the wide variety we are finding? FYI, this has nothing to do with being “upset.” It has to do with valid objection to a lousy classification system.

      2. What objects larger than Pluto are out there? So far, not a single one.

        Triton – moon of Neptune; suspected to be a captured Kuiper belt object: Diameter – 2700 km (Pluto: ≈2330 km); Mass – 2.14 × 1022 kg (Pluto: 1.31 × 1022 kg).

        So, stick that in your pipe and smoke it!

      3. Ivan, I thought we were talking KBOs, planets and dwarf planets, not moons of giant planets such as the mighty Neptune. All the same, I commend you for thinking of Triton, which is a very cool moon, indeed.

      4. The point that I am trying to make is this: Triton (a moon of Neptune) is bigger than Pluto; therefore, since Pluto is such a pipsqueak, it does not qualify as a fully fledged planet – period!

      5. Pluto is larger than Eris, Ivan. It is 2/3rd the size of the moon, and the largest-known KBO, and was a planet for 76 years, longer than Ceres, I believe. It meets all the criteria for being a planet, except for one that the Earth also does not meet, as we,too, have not cleared our orbit, since two asteroids share our orbit, at least. It is also big enough to have four moons.

      6. No. Pluto is less than 18% as massive as our moon. And Eris out-masses it by 30%, weighing in at 23% the mass of our moon.

      7. Again, the measurement that matters is that of the threshhold for attaining hydrostatic equilibrium. Pluto and even Ceres clearly meet that threshhold.

      8. Wrong. Pluto is large enough and massive enough to be rounded by its own gravity, which according to the geophysical planet definition, is enough to make it a planet. Triton, being spherical, is a secondary or satellite planet.

      9. “Besides, with larger objects than Pluto out there, what, do you want a solar system in 50 years with 100 planets?”

        This question specifically referred to Kuiper Belt Objects. There are no known KBOs larger than Pluto. Triton may have originated as a Kuiper Belt planet, but it is commonly viewed as a moon of Neptune, not a Kuiper Belt Object.

  2. Laurele,
    Mike Brown is known as “plutokiller” because he had a huge part in discovering the objects that brought up the original debate at IAU, not because it was necessarily his idea to reclassify the objects in the solar system.

    Do you really take this that seriously or was your post a Poe?

    1. But it is the journalistic community that keeps focusing on this “plutokiller” thing, which has no basis in science and largely appeals to sensation. As I said above, the debate existed long before Eris’s discovery and continues in spite of what happened at the 2006 IAU meeting. That decision is widely recognized by many astronomers as not having been the IAU’s finest hour.

      I don’t know what a “Poe” is, but yes, I take this issue seriously enough to have written a blog for five years and to be writing a book on the subject. In fact, I’m now in graduate school studying astronomy largely because of Pluto. Why are you okay with Brown taking it so seriously but question someone on the other side of the debate doing the same?

      1. A Poe is but a google or an encyclopedia away:

        “Poe’s law, named after its author Nathan Poe, is an Internet adage reflecting the fact that without a clear indication of the author’s intent, it is difficult or impossible to tell the difference between sincere extremism and an exaggerated parody of extremism.”

        Yes, you are so extreme some of your audience laugh as the first response. For example, “his “plutokiller” thing, which has no basis in science” – it was precisely the _science_ of object populations in general and Kuiper objects in particular that led up to the decision which the _science community_ made. You can google up those papers too, but essentially Kuiper objects doesn’t aggregate as planets nor behave as them in orbits (doesn’t mass enough to dominate over the time scale of the solar system).

        So what would you place against such a response? You say you have blogged for five years, you are writing a book on an astronomical topic and _then_ you are a graduate astronomy student – and a student motivated “largely” by this topic. Either that is comical or sad; excuse us for choosing the lighter version.

        And, as in evolution, AGW, and other closed science topics, there is no “debate”. There may be an open question in some areas, in this case which definition is the better one. But that is far from important to make science progress. You should know, or learn, the difference between societal debate on social matters and science review on science matters if you go in graduate school.

      2. “There is no debate?” Sorry, but that statement is little more than your opinion. The fact that this topic remains a matter of discussion in professional organizations such as the American Geophysical Union and the European Geophysical Union, in publications, and in university classrooms–and the fact that the New Horizons mission continues to refer to Pluto as a planet–indicate your statement is not accurate.

        The notion that an object has to gravitationally dominate its orbit to be considered a planet–specifically, the dynamical planet definition–is one legitimate viewpoint but not the only one. It focuses on how objects affect other objects, requiring gravitational dominance to classify an object as a planet. This definition is very much about where an object is rather than what it is. Equally scientifically legitimate is the geophysical or planetary science definition, which focuses on individual objects themselves. Under this definition, if an object orbiting a star is large enough to be rounded by its own gravity, regardless of where it is, it is a planet. These are two different ways of looking at the facts; neither is right or wrong. I don’t know how you judge an issue “closed,” but if active discussion continues as it does in the case of planet definition, any declaration of it being closed is premature and worrisome in that it totally cuts off debate.

        I believe that how objects like Pluto and Eris are classified should be based on these objects themselves, not on the characteristics of other objects or populations of objects.

        I stand by my statement that there is no scientific value in Brown calling himself “plutokiller.” He is the one who blurs the distinction between joking and serious discussion, the one who chose “killing Pluto” as part of his book title.

        So, it’s comical or sad that I, who disagree with you, choose to go into astronomy and focus on Pluto and the outer solar system, but it’s admirable when someone like Brown, who agrees with you, does it? Many people choose to go into astronomy after being inspired by observation of astronomical objects, public events such as the Apollo missions, etc. Are their decisions “comical” or “sad?” Or is that only true if someone decides to enter the field “later” in life? Given that I am pursuing a degree and have performed well in my classes, it is reasonable to assume my interest in astronomy goes beyond Pluto.

    2. I see no indication that laurele was doing a Poe. As far as seriousness goes, is Mike Brown doing a Poe calling himself “plutokiller” on Twitter and with the title of his book? In his case, I also submit he is not. My colonoscopy comment regarding why Neptune is laying on its side, though, was possibly a Poe, but I am not a fan of term as I find it obscure and bound to remain such. Edgar Allan Poe was a serious man, and I also find the term to be disrespectful to his memory, because not many people will equate the term with Nathan Poe. If he (Edgar) was a comedian, I would not have a problem with it. He should not need such a term to be remembered by today’s generations who should read the classics more and horridly-titled narcissistic books less.. The term reminds me of the Urban Dictionary Word of the Day. Most of them are pretty lame.

    1. What formula did you use to calculate your ‘wind chill’ factor? As the isochoric heat capacity and isobaric heat capacity of Methane would be quite different than earthly comparisons.

  3. Mike Brown is known as “plutokiller” because that is his Twitter name. Of course, Pluto is not dead and may even have life deep below a frozen ocean. Mike Brown’s claim to have killed Pluto is unprofessional and narcissistic. His claim that Pluto huggers are liars is also unprofessional. He should stick to what he is good at, co-discovering dwarf planets. He should also stop claiming to be the sole discoverer of Eris and a few other dwarf planets that he merely co-discovered. I wish a journalist would interview Chad and David to see what they think of his outrageous, disrespectful behavior. If you look up Eris on Wikipedia, you can confirm that he is the mere co-discoverer, yet every book review I have read on his recent book fails to mention this. I find this lapse in journalistic integrity very disturbing, and it makes me wonder if Mike Brown is telling his interviewers that he is the sole discoverer as it should anyone who can think their way out of a paper bag.

    1. “yet every book review I have read on his recent book fails to mention this”.
      Maybe you should read his book instead of relying on reviews. I am just reading his book and he duly mentions Chad’s role in discovering Quaoar. I have not finished the book yet, though.

      1. I will never read the book that gleefully delights in killing Pluto in its title, nor should any sane person. If it was the only book left on the face of the Earth, I would refuse to read it. I cannot think of a more wretched title for a book.

      2. Whoa, you seem like a horrible person. Why would anyone cry about a title of a book? I suspect a huge amount of jealousy.

      3. I am not crying, nor am I horrible or jealous. I am not the one who says Pluto huggers are liars. I am not the one who makes money by claiming to be the sole discoverer of Eris when two others are co-discoverers. I am not the one who uses a sensationalistic title of a book to sell a narcissistic, self-indulgent, megalomanical rant, denigrating Pluto and rambling about his family on a strange tangent as if no one was willing to stand up to him and edit the book. With all the great books in the world, why would anyone choose to read this one?

      4. You do seem to know a lot about his book despite never having read it. It really seems that its title hit a nerve with you. I found the title a bit ironic, but really not self-indulgent, let alone megalomanical, once I started reading the book.
        But judging a book from its cover is almost like calling something a planet without taking a good look at what’s behind it.

      5. Yes, it hit a nerve, as does his Twitter name. I have always loved Pluto and will always love Pluto, and he is gaining notoriety at the unjust expense of Pluto, making absurd claims. Pluto is a not a comet. Earth does not clear its orbit, either. What do you think of this inflammatory statement by him?

        He says, regarding those who view Pluto as a planet: “And honestly, I think manipulative is the word. They don’t believe what they say, they know what they say is not true and they say it in ways that are deceitful. That is maybe a strong statement to make, but they know what they are saying is not true. That bothers me. You shouldn’t say things that you know is not true just to make a point.”


      6. I’ll agree that “false” and “true” qualifications are not the way to discuss naming conventions.

      7. LOL. Grow up. You are not 5 year old anymore.

        You can love Pluto all you want, whether it’s a planet or not.

      8. The point here is that in this statement, Brown accuses respected scientists of not really believing their own publicly stated positions. Brown may not agree with the views of astronomers such as Dr. Alan Stern, but how can he presume to know what they are thinking and accuse them of lying? That is just plain unprofessional.

      9. He could be an assholish visionary genius using science, politics and everything. Beat him. 😀

        Do the same thing as him and then I’m gonna stalk you for a while and finally marry you because it’d be so hot. Yeah, I really need some non-comformist actress and astronomy superstar. 😀

      10. Sounds like we’re back to the ad hominem attacks again. I am not stalking anyone, and I am not looking to win a contest, but to put forward a broader planet definition than that of the IAU and to inform people that this debate is far from over.

      11. Wow, a double Poe! Thank Zod and Zom for non-conformists! Bertrand Russell once said, “Conformity is death!” By the way, Mike Brown may be a genius in co-finding KBOs, but if he is, using modern technology to ape Clyde Tombaugh’s efforts, then surely the great discoverer of Pluto is a greater genius–sort of like comparing Mt. Everest to Magic Mountain Amusement Park.

      12. Oh, yeah, sorry, HeadAroundU, I forgot I am 50, that whole times ten thing screws me up sometimes…..thanks for reminding me!

      13. By the way, I have seen Pluto through a large portable telescope near Cadillac, Michigan. I was a member of the Warren Astronomical Society at the time. Pluto is very beautiful. It was pretty dim and grey, but breathtakingly wondrous. I also saw the New Horizons launch on January 19, 2006 from Jetty Pier in Port Canaveral, Florida. That, too, was wondrous. I also asked President Bush, when I met him, to support the New Horizons mission back in 2002, and he quipped, “I’m gonna send YOU to Pluto.” Luckily, did not defund the mission, as President Clinton did to the Pluto Express mission. It may, eventually, be known as the greatest achievement of President George W. Bush’s presidency. Thus, I did “take a good look” at it.

      14. I share your excitement on the New Horizons mission, I really do, but I am equally excited about the good look that the NH probe will take at what’s behind it (meaning Pluto). And if you love Pluto so much, I am sure that you will equally appreciate the other KBO that will be explored.

      15. I am working with Zooniverse’s Ice Hunters KBO search and look forward to analyzing the data on both Pluto and the chosen KBO(s), as the latter will not be in hydrostatic equilibrium. At that point, we will have serious data to determine just how alike and different Kuiper Belt planets are from tiny Kuiper Belt Objects.

      16. I have taken the best look possible at the limited data we have on Pluto. Until the New Horizons flyby, we know very little although the data we do have show Pluto to be a complex world with geology and weather, that could even host a subsurface ocean and microbial life.

        As a writer, I see words and choice of words as important and believe Brown could have chosen a much better title. This one is just plain silly.

      17. Nobody here is a “horrible person.” Some of us, when choosing to read an astronomy book, want to read about astronomy, not about the author’s family life. I personally think the title of Brown’s book is misleading and egocentric and that refering to the discovery of Eris would be more appropriate. Plus, he talks about his daughter in his book, and his daughter has already rejected the demotion of Pluto and made it clear she sees it as a planet. It is therefore unfair to her to be identified with “killing” Pluto when she is opposed to that. And no one here is jealous; that is an obvious ad hominem attack.

      18. Now his daughter (six years old, isn’t she?) may think about it all she likes, how could it be “unfair” to call the book “How *I* killed Pluto”? Could I not voice a certain opinion, even if it would be different from my six year old daughter *supposed* opinions? Are you really serious that you are taking issue with that?

      19. What he does seems a lot like a political maneuver to make him appear more palatable to the public. Of course he can take a position different from that of his daughter, but he should consider that down the line, she might be unhappy to be so identified with a book about him “killing” Pluto, especially since he discusses her in the book. Again, that’s why he would have done better to choose a different title.

      20. Perhaps you assume the book deals with the killing of the nice and kind Disney character known als Pluto, but I can assure you that it only concerns the discovery of KBOs and the naming of planetary bodies.

      21. No, the book that deals with the dog is Neil deGrasse Tyson’s book, which I did read. While I disagree with Tyson’s conclusion, he at least stayed on topic regarding the science and has since admitted the debate is still open.

      22. I would be interested in what your impressions are regarding his accrediation of Eris when you get to that, Mr. Van Nieuwenhove. You should get a medal (and a barf bag) for being able to read his book. I simply cannot sink that low, but that is just me and I do not condemn you for reading it. For me, it would be, though, like swimming in a pool of vomit.

      23. Well, if it is really a pool of vomit, a barf bag is not going to help me much, is it?

      24. I would be interested in what your impressions are regarding his accrediation of Eris when you get to that, Mr. Van Nieuwenhove. You should get a medal (and a barf bag) for being able to read his book. I simply cannot sink that low, but that is just me and I do not condemn you for reading it. For me, it would be, though, like swimming in a pool of vomit.

    2. “yet every book review I have read on his recent book fails to mention this”.
      Maybe you should read his book instead of relying on reviews. I am just reading his book and he duly mentions Chad’s role in discovering Quaoar. I have not finished the book yet, though.

    3. I think Brown makes a very appropriate response to the fact that he was denied the opportunity to be planet discoverer. He may become more famous as “Pluto killer”!

      And, while you make some fun and some pertinent points, I think you could adopt Brown’s ability to turn grapes into wine. Your choice, natch.

      1. When it comes to jokes, Brown can dish it out, but he can’t take it. I’ve kidded around in my tweets, with my choice of the name “plutosavior,” and he has practically accused me of stalking him.

        Brown was NOT denied the opportunity to be a planet discoverer. He made that choice of his own volition. In fact, he was for Pluto and Eris being classed as planets before he was against it. That makes one question, why the turnaround? I think it is much better scientifically and educationally to become known as a planet discoverer than as a “planet killer.” For one thing, the latter confuses kids, who then think Pluto really is gone. And it’s not scientific because no “killing” has taken place.

        Those of us on the pro-Pluto as a planet side have plenty of fun and laughs ourselves. We even share Brown’s affinity for science fiction and astronomy in entertainment. He’s created a “character” centered on the notion of having “killed” Pluto; I’ve created a “character” centered on the notion of “saving” Pluto. The fun is a huge part of this whole deal.

    1. Because that’s probably a combination of our perspective from Earth and the photographer not knowing which way is “up” relative to the disk of Neptune.

      1. I once asked Neptune, “What is up?” He replied, “Dude, the IAU is messing with my little brother, Pluto!”

  4. As fare as I concern Pluto is still a planet if it a dwarf planet what does that make the inner planets medium planets by size they should be considered dwarf planets to.

    1. Well, there is the scientifically accepted definition of planet and the “nostalgic” version.

      Personally I would be much more warmed by “nostalgic planets” if those who clings to old culture would have first, or at least also, supported Ceres for planet. After all, it was demoted for precisely the same reason as the Pluto-Charon system. It turned out decades later that it was part of a larger population unrelated to planets as we know them.

      But in an ironic twist of fate it seems Ceres is more of a planet than the giant comet Pluto is. Ceres is likely a planetoid. But so, it seems, is Mars! That explains its rapid formation (~ 3 Ma against Earth ~ 30 Ma) and its inhomogeneous differentiation and lack of global intrinsic magnetic field.

      True, Mars dominates its neighborhood. But in latest models of planetary formation it was Jupiter that stopped Mars aggregation towards bona fide terrestrial, and first cleared its orbit.

      So who cares about that remote little cold hell hole inhabitant that is named Pluto. It is Ceres that grows on you: “It is named after Cer?s, the Roman goddess of growing plants, the harvest, and motherly love.” =D

      1. Ceres is a planet, and if you read my blog and online comments, you will see that I have always supported this position. The demotion of Ceres turns out to have been incorrect. That is because 19th century astronomers could not resolve Ceres into a disk, so they had no clue that it is any different from the other asteroids in the field between Mars and Jupiter. Today, we know Ceres is spherical and meets the geophysical/planetary science definition of planet, as it is a non-self-luminous spheroidal body orbiting a star. When Dr. Alan Stern coined the term “dwarf planet,” he intended it to refer to a third class of planets in addition to terrestrials and jovians, small planets large enough to be rounded by their own gravity but not large enough to gravitationally dominate their orbits. He never intended for dwarf planets to not be considered planets at all. In fact, establishing dwarf planets as a subclass of planets is consistent with the use of the term “dwarf” in astronomy, where dwarf stars are still stars, and dwarf galaxies are still galaxies.

        Support for the geophysical planet definition has absolutely NOTHING to do with nostalgia or emotion. That is a straw man tactic used by those who support the IAU decision to discredit their opponents. There are TWO scientifically legitimate planet definitions, the dynamical and the geophysical. Neither is “better” than the other.

        Pluto is not a “giant comet.” Its orbit may be eccentric, but it is not like the orbits of comets, which take them into the inner solar system. Pluto is 70-75 percent rock and geologically differentiated into core, mantle, and crust, while comets are mostly ice. Comets lose mass with every orbit around the Sun; Pluto does not. Many giant exoplanets have orbits far more elliptical than Pluto’s and also have tails. Mercury has a tail as well due to outgassing; that does not make it a comet.

      2. Thanks for clearing that up, laurele. Ice is nice, but not as nice as Pluto. It is goofy to think Pluto is not a planet.

  5. May be, I did not understand some of the comments, but it looks like there are ad hominem attacks. Stop this, please!

    1. I am trying to avoid ad hominem attacks, Mr. Ivry, but I see your concerns and will try to modulate a bit better.

    1. I am not only a Pluto lover, I am also a Pluto hugger. But as far as getting over myself, I have never tried to make money on a book claiming to kill a planet in its title. I dare him to try to kill Jupiter, too. I think Jupiter will win, especially if he gets too close.

  6. I don’t know Mike Brown anymore than I know Jason Major, but I think it was wrong to refer to Mr. Brown as the “confessed (and remorseless) “Pluto Killer.” Such words are completely irrelevant to the article presented here and serve only to bring up a sore subject. That sore subject is the focus of the discussion here and not the otherwise well written article presented.

    My biggest complaint about science in general is the terminology used to define everything in some sort of group. Our students spend more time focusing on the terms of science than on the science itself. When kids study astronomy; that which gets called a planet gets some attention in the textbooks and anything relegated to a lessor status gets little or no coverage at all. Just calling Ganymede a moon gives it a lessor status though it is larger than Mercury. “What’s in a name?”

    1. The problem is that very little time is spent on astronomy in school. I completely support the notion of giving coverage and time to the large moons of planets, especially now that we’ve sent probes that have imaged them and obtained detailed information about them. Some of these are worlds that could potentially host microbial life in subsurface oceans. Decades ago, we knew very little about these moons, which is likely why not much was taught about them. It’s not an either/or but a both/and situation regarding giving attention to both planets and moons.

    2. I don’t think calling a moon a moon is to insult it at all. If I don’t call broccoli cauliflower, am I insulting the broccoli?

    1. It is logical to have a body such as the IAU to decide certain matters, like names of planets and moons. The problems only arise when such an august body shirks its duty to act circumspectly as was the case in Prague. Hopefully a large contingent of Pluto huggers will converge on Honolulu in August 2015, including myself, and inspire the IAU to reverse itself and once again be all it was meant to be.

      Without such a body, everyone could call Pluto by their own chosen name. Some would call it Goofy. Neptune could be called Poseidon. Some might still call Eris by Mike Brown’s first choice of Xena, named after a teevy show–talk about a “Poe!”(“Teevy” is how The Los Angeles Times spelled TV, circa 1981–and I think it is a better spelling as TV sort of deifies the boob tube with its capitalization, as if it were Zod or something……)

      1. TV does have a zombifying effect on people, so maybe the “Zod” reference should really be “Zom.”

  7. Regardless of how we chose to classify and object, it is there.

    Pluto is still there, still has the same mass, and newly discovered moons. I’m sure it is not offended to be re-labeled as a “dwarf planet”. While I do not fully agree with IAU definitions, my concerns have more to do with exo-planets, as their orbits can be much more elliptical and complex.

    1. Yes, but will people still know these facts about Pluto if it is simply excluded from discussions and models of the solar system? The issue isn’t whether Pluto is offended; it’s the resulting blurring of the distinction between small planets and asteroids that is at issue here. Given the diversity of types and locations of exoplanets we’ve found, it’s inevitable that we will have to expand rather than contract our definition of planet to include these new objects.

      1. It should not be excluded, but the new term sends interest to other dwarf planets as well, which makes the Solar System more interesting, in my opinion.

        Gas Giant planets, Terrestrial planets, dwarf planets. We basically just went from to types to three types, the later of which covers a wide number of bodies that are smaller than typical planets, but larger than asteroid/comets.

      2. I think we’re mostly in agreement with one another. There are three, not two types of planets. The entire debate would be resolved if the IAU resolution were amended to establish dwarf planets as a subclass of planets.

    1. There is actually a connection between Pluto and Edgar Allan Poe. Pluto was named after the Roman god of the underworld. In his poem “The Raven,” the main character has a raven fly into his home and refuse to leave. In one line, the man says, “get thee back into the tempest and the night’s Plutonian shore” referring to the underworld (Pluto the planet had not yet been discovered). The raven’s answer is exactly what I say when people say to give it up and accept the IAU definition: “Nevermore.”

  8. The central issue here is not specifically the classification of the Kuiper Belt object Pluto. It’s about the importance of classification in science. Classification is often crucially important in making sense of complex matters. To see this, you need only look to the value of the Linnaean taxonomy, or even better, the Periodic Table of Elements. Should classification be decided by public opinion poll as so many, including some posting under this story seem to think it should?

    Should the public be allowed to vote upon which column of the Periodic Table they think their favorite element should be put in? Maybe raise it to a higher row to get it a little more notariety?

    Clearly, no. We’d never have gotten basic chemistry worked out in the midst of that kind of chaos.

    And clearly, Pluto fits much better as a Kuiper Belt object than as a planet. The only reason it was ever misclassified in the first place is that we got Neptune’s orbit wrong. Thus the misguided “Hunt For Planet X” was on, and by the gods, we were gonna find ourselves a planet, no matter how hard we had to knock that round peg into a square hole.

    Personally, all the weeping and moaning about Pluto’s reclassification is just stupid and trivial. But it is not specifically the Pluto thing that is most important. It’s the underlying principle of whether public opinion polls should be allowed to determine scientific classifications. And taking a strong position on that is far from stupid or trivial.

    Think about it.

    -Steve Bergman

    1. I thought about it and you are wrong. Pluto meets two of three of the IAU’s elements for planethood, as does Earth. Thus, if Pluto is not a planet, nor is Earth. Have you followed this issue at all? It seems as though you just wanted to “weigh in,” throw in a “stupid” and a “trivial” into your post and send it. You might want to study the issue before calling the other side stupid. Nice chemistry analogy, but it is not the end all and be all of the debate. Nor is everyone here a lay person in astronomy. Just a thought. You don’t need to think about it, though, if you don’t want to.

    2. I have thought about this a great deal, as have the many astronomers who continue to reject the “reclassification,” which is based on the false notion that there can be only two kinds of planets. The comparison with the Periodic Table is not valid because the elements are clearly distinguishable by the unique propeties of their atomic structures. Elements are presented by increasing atomic number, the number of protons in an atom’s atomic nucleus. These are measurable facts. In contrast, the question of Pluto’s status is a matter of interpretation. We know the diameter, mass, density, orbital parameters, etc. for Pluto; these are not in doubt. Whether or not these facts make Pluto a planet depend on how the term planet is interpreted–a subjective rather than an objective criterion. The geophysical planet definition, according to which an object must simply be rounded by its own gravity and orbit a star to be a planet, is just as scientifically valid as the dynamical planet definition, which focuses on where an object is, requiring it to gravitationally dominate its orbit to be defined as a planet. We are talking about two different ways of looking at the same facts. Neither way is scientifically wrong.

      It was the leadership of the IAU that came up with the notion of voting on this to begin with, so you should take issue with them. Most who voted are not planetary scientists, meaning they don’t study planets. The entire idea of holding this vote was a mistake. Ideas rise and fall on their own merit over time. Nobody voted on relativity, gravity, whether we have one or billions of galaxies, etc. The IAU does not even encompass the entire astronomical community. Their votes should be limited to their own internal policies and procedures. Plus, you dismiss the objections of a large number of planetary scientists who formally rejected the demotion. It was a political decision, and that is why it is rejected by such a wide range of people.

      Pluto fits as BOTH a Kuiper Belt Object and a planet. Why is this so hard to understand? The first tells us where it is; the second tells us what it is. Yes, there can be small planets scattered among belts of tiny objects. Their location alone does not make them not planets. Pluto fits perfectly well with the planets once we add a third category, dwarf planets, for objects large enough to be in hydrostatic equilibrium but not large enough to gravitationally dominate their orbits. It may have been discovered through a search for something else (a gas giant), but that does not make it any less a planet. Pluto was never “misclassified.” Its discovery simply predated the discovery of other planets of the same category by many years.

      The situation is similar to the addition of new stellar categories to the Herzsprung Russell Diagram once brown dwarfs were discovered. We found another type of star previously unknown and accordingly made an addendum to the classification system.

      When you use terms like “weeping and moaning,” you are discrediting those who reject the IAU definition with the implication that we are motivated by our emotion. That argument has been used for five years, and it is simply wrong. Supporters of Pluto’s planet status base our view on a legitimate scientific principle, the geophysical planet definition. We are understandably disappointed when people, even those with PhDs, try to pass off a decision made by and for political purposes, as scientific, and by a wrongful declaration that the debate over planet definition is over when it is not.

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