Pluto a Planet Again? It May Happen This Year

By David A. Weintraub, Vanderbilt University | February 25, 2015 12:22 pm


[Keep up with the latest news on New Horizons here]

Ceres is the largest object in the asteroid belt, and NASA’s Dawn spacecraft will arrive there on March 6.

Pluto is the largest object in the Kuiper belt, and NASA’s New Horizons spacecraft will arrive there on July 15.

These two events will make 2015 an exciting year for solar system exploration and discovery. But there is much more to this story than mere science. I expect 2015 will be the year when general consensus, built upon our new knowledge of these two objects, will return Pluto and add Ceres to our family of solar system planets.

The efforts of a very small clique of Pluto-haters within the International Astronomical Union (IAU) plutoed Pluto in 2006. Of the approximately 10,000 internationally registered members of the IAU in 2006, only 237 voted in favor of the resolution redefining Pluto as a “dwarf planet” while 157 voted against; the other 9,500 members were not present at the closing session of the IAU General Assembly in Prague at which the vote to demote Pluto was taken. Yet Pluto’s official planetary status was snatched away.

Ceres and Pluto are both spheroidal objects, like Mercury, Earth, Jupiter and Saturn. That’s part of the agreed upon definition of a planet. They both orbit a star, the Sun, like Venus, Mars, Uranus and Neptune. That’s also part of the widely accepted definition of a planet.

Planet Problems

Unlike the larger planets, however, Ceres, like Pluto, according to the IAU definition, “has not cleared the neighborhood around its orbit.” The asteroid belt is, apparently, Ceres’ neighborhood while the Kuiper Belt is Pluto’s neighborhood – though no definition of a planet’s neighborhood exists, and no agreed upon understanding of what “clearing the neighborhood” yet exists. Furthermore, no broad-based agreement exists as to why “clearing the neighborhood” need be a requirement in order for an object to be considered a planet.

Some planetary astronomers would argue that were the Earth placed in the Kuiper Belt, it would not be able to clear its neighborhood and thus would not be considered, by the IAU definition, a planet; apparently location matters. Here a planet, there not a planet. I’d argue that location shouldn’t matter; instead, the intrinsic properties of the objects themselves should matter more. And so we are led back to Ceres and Pluto.

Never before visited by human spacecraft, Ceres and Pluto, as we will soon bear witness, are both evolving, changing worlds. Yesterday, Ceres and Pluto were strangers, distant, barely known runt members of our solar system. By the end of this calendar year, however, we will have showered both objects with our passion and our attention, we will have welcomed them both into our embrace. And we almost certainly will once again call both of them planets.

Two views of Ceres acquired by NASA’s Dawn spacecraft on Feb. 12, 2015. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Two views of Ceres acquired by NASA’s Dawn spacecraft on Feb. 12, 2015. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Ceres, Temporarily a Planet

Ceres was discovered on New Year’s Day in 1801, by Italian astronomer Giuseppe Piazzi, a member of an international team of astronomers dubbed the Celestial Police, who were searching for a supposedly missing planet in between the orbits of Mars and Jupiter. When discovered, Ceres was immediately recognized as a planet, the eighth one known at the time (neither Neptune nor Pluto had been discovered yet).

But within a few years, other objects in the asteroid belt were discovered and Ceres no longer seemed to stand out as far from the crowd. In 1802, the great astronomer William Herschel suggested that Ceres and Pallas and any other smaller solar system objects should be called asteroids – meaning star-like. In telescope images, they were so tiny that they looked point-like, like stars, rather than disk-like, like planets. And so, more than a century before Pluto was discovered, Ceres was plutoed.

What is Ceres?

But Ceres does still stand out. It’s the largest asteroid, by far, nearly 1,000 kilometers across (twice as large in diameter as Vesta, the second largest asteroid), though not perfectly spherical in shape.

As happened inside Earth and other planets, planetary scientists think that long ago, the denser material in Ceres separated from the lighter material and sank to form a core.

Astronomers think Ceres is rich in water – as much as one-third of Ceres might be water – and may have a thin atmosphere. Bright, white spots on its surface might even be large frozen lakes. Ceres may, in fact, have as much fresh water as Earth, have Earth-like polar caps, and might even have a sub-surface liquid ocean layer, like Jupiter’s moon Europa and Saturn’s moon Enceladus.

Beginning this month, we’ll start to learn more about these tantalizing possibilities. With our increasing knowledge of and familiarity with Ceres, we will no longer be able to identify meaningful criteria that will allow us to continue to classify Ceres as not-a-planet. Ceres will continue to be a small planet, but in 2015 we will come to understand that dwarf planets are planets, too.

Hubble images of Pluto taken in 2010.  NASA, ESA, and Marc W. Buie (Southwest Research Institute)

Hubble images of Pluto taken in 2010. Credit: NASA, ESA, and Marc W. Buie (Southwest Research Institute)

Pluto’s Short Planetary Reign

When Pluto was discovered by Clyde Tombaugh in 1930, many astronomers were certain that a large planet orbited the Sun beyond Neptune. Instead they found Pluto, which turned out to be small compared to Earth and Neptune, though more than double the size of Ceres, with a diameter of 2,300 kilometers.

Pluto also has an unusual orbit, as it crosses Neptune’s orbit, though it does so in such a way that it can never collide with Neptune.

Pluto’s modern-day troubles began in 1992, when astronomers David Jewitt and Jane Luu discovered the first objects in the region of the solar system now known as the Kuiper Belt. Whereas the asteroid belt where Ceres resides is made mostly of house- and mountain-sized rocks that orbit the Sun in between the orbits of Mars and Jupiter, the Kuiper Belt is made mostly of house- and mountain-sized chunks of ice that orbit the Sun beyond the orbit of Neptune. Pluto, as it turns out, is one of the biggest objects in the Kuiper Belt.

What is Pluto?

Pluto is the last unexplored planet in our solar system. And the Kuiper Belt may contain hundreds of other planetary worlds like Pluto. These may be the most numerous worlds in the solar system; they may contain, together, the most total surface area of all the solid-surfaced planets.

Pluto has one large moon, Charon, and at least four small moons: Nix, Hydra, Kerberos and Styx. It has an atmosphere that expands and contracts as Pluto warms and cools during its 248 year orbit around the Sun. The surface is likely rich in water ice, enriched with methane and nitrogen and carbon monoxide frosts; these ices might contain complex organic molecules.

The New Horizons mission is poised to answer some of our myriad questions about Pluto. How did it form? What is the atmosphere made of? What is the surface like? Does Pluto have a magnetic field? What are the moons like? Does Pluto have a subsurface ocean? Is the surface of Pluto’s moon Charon pure water ice?

Pluto has guarded its secrets for four and half billion years. But in a few months, a few intrepid humans will pull back the curtain on Pluto and say “Hello, Pluto, we’re here.” And Pluto will begin to share her secrets with us. When she does, as with Ceres, our familiarity with Pluto will help us recognize that Pluto is, was, and has always been a planet, albeit a small one.

We only get to visit Ceres and Pluto for the very first time, once. This year. March 6 and July 15. In your lifetime. In this incredible year of the dwarf planet. Get ready to party. Ceres and Pluto are coming home.

The Conversation

Top image by International Astronomical Union

This article was originally published on The Conversation.

CATEGORIZED UNDER: Space & Physics, Top Posts
  • rolando


  • TalkingMoose

    The “Pluto is a planet” clique is basing its opinion on sentimentality, not science. Even as a kid I was confused as to why Pluto was the only “planet” with a skewed orbit, and one so elliptical that it gets closer to the Sun than Neptune at it’s closest approach. IF all planets were formed form a single disc of dust, should they ALL be co-planar?

    But we all grew up being taught Pluto was the 9th planet and some people just can’t let go. So let’s go on believing that Pluto is a planet, Columbus proved the Earth was round, George Washington chopped down a cherry tree, Brontosaurus existed, and whatever other misinformation we were given in our youth because that’s what science is about after all: sticking to our beliefs in spite of new evidence. Right?

    • Guy Faulkes

      What’s wrong after all with the designation of “dwarf planet”? It’s a sub-set of Planet anyway, it just means “extra-small planet.” Some folks get so emotional over mere semantics.

      • john doe

        I prefer using minor planet, it brings to mind the indication that it’s not fully matured yet, instead of being stunted lol

        • The Man

          FULL Planet. FULL Stop.

        • laurele

          Minor planet is inaccurate because that term is already in use as a synonym for asteroids and comets, objects not large enough to be rounded by their own gravity (those the IAU calls “Small Solar System Bodies”).

      • laurele

        Actually, the problem isn’t with the term “dwarf planet”; it’s with the idea that dwarf planets are not planets at all. That was not the intention of the person who coined the term, Dr. Alan Stern. In astronomy, dwarf stars are still stars, and dwarf galaxies are still galaxies. The only reason some people do not want to call dwarf planets a subclass of planets is a sentimental objection to our solar system having “too many planets,” even if the latter is reality.

    • Aaron Link

      Scientific re-categorization ≠ paleontological fallacies and historical anecdotes

    • john doe

      lol you had a point, aaaaand then you lost it. Planets aren’t dependent on their orbit being non-elliptical. Much like the surface is never 100% spherical, neither is the orbit going to be 100% circular(even earth’s orbit around the sun is slightly elliptical, but slightly, only slightly)

      • Angela Zalucha

        Hindsight is 20/20. He was asking the same kind of questions scientists ask. While his observations ultimately didn’t make it into the planet definition, this is the way scientists think, and a number of ideas about what constitutes the definition of a planet were thrown around before the current one was in place.

      • TalkingMoose

        It’s not just the eccentricity of the ellipse, but the orientation. All of the “established” planets are relatively co-planar. Pluto ‘s orbit is skewed, like the orbit of a comet.

    • Kyle McAfee

      Well honestly I would contend that it’s not childish nostalgia keeping the argument of Pluto’s previous denomination as a planet alive, but rather the upstart crowd of eager astronomers entering the field that have made a redundant and preposterous change to nomenclature that was driven by their desire to be a part of something and should be recalled. Does it make any sense that a massive gaseous celestial body such as Jupiter would be declared under the same name as a relatively minuscule terrestrial planet like Mercury? Yes, you know why? Because the dictionary definition of a planet is simply a celestial body that orbits a star and though when referring to them we may say “gas giant” or “rocky planet” we still call them both planets. Yet for some reason, in spite of the fact that there is more in common in volume, mass and composition between Earth and Pluto than there is between Earth and Saturn we still call Saturn a planet and Pluto a dwarf or twin planet. Why? Because it’s difficult to make a name for yourself in astrology and people want to constantly deviate their time to medial actions that they know that they’re capable of and know they can be a part of. The circumstances of Pluto’s odd orbit are irrelevant; it is still clearly a large celestial body orbiting the sun and it’s large enough to have at least five of it’s own permanent satellites.

      • Angela Zalucha

        Key point: astronomy, not astrology.

        It’s actually not young scientists who are leading the charge, senior scientists are deeply ingrained on the Pluto is a planet siide. But you also bring up a good point about gas giants vs. rocky planets. As the number of exoplanets that have been observed increases, some are more Jupiter like than star like. The definition of a (main sequence) star is an object that sustains nuclear fusion. But people call brown dwarfs stars, even though they don’t sustain nuclear fusion. So then, rhetorically, are they planets?

        • Rational Muslim

          I think that if there is no physical surface on which to land, it is rather difficult to consider it a “planet”.

          • Angela Zalucha

            Fair point. But we think Jupiter and the sun do have physical surfaces, sort of. whether or not you suddenly hit a hard surface or it is a gradual transition is not known. One day when it becomes feasible to go deep enough we may have another argument…..

        • TheSinndogg

          A lot of people DON’T call brown dwarfs stars or planets, actually, and with good reason. Brown dwarfs’ internal properties are like neither, so they’re best placed in their own category (called- surprise, surprise – brown dwarfs).

          • Angela Zalucha

            Alright. So then how come nobody lost their marbles over this? Settle down Pluto people….

          • laurele

            To be fair, the people on the “Pluto isn’t a planet” side are just as passionate and intense as those on the “Pluto is a planet” side. Using terms like “lost their marbles” for only one group in an ongoing debate could be viewed as a way of trying to demean members of that group.

        • laurele

          I think the idea with brown dwarfs is that at one point they conducted fusion in their core, even if they no longer do so. They may have fused deuterium rather than hydrogen.

          We need a schematic for planets similar to the Herzsprung-Russell Diagram for stars. That or we need to seriously look at the Star Trek planet classification system. Either way makes room for numerous subcategories under the broader umbrella term “planet.”

        • John Rooksby

          Key point: ‘rhetorically’. Since people call brown dwarfs ‘stars’ even though they don’t sustain nuclear fusion, they remain, rhetorically, stars. We talking about the general public here, not cosmologists. When scientists (in any field) talk to laymen they must simplify their language or risk not being understood. Indeed, this goes for any expert in any field since all fields of expertise develop their own jargon that the layman will not understand. A dictionary of astronomical terms would be a book intended for astronomists, cosmologists, etc. A dictionary (which will contain a few astronomical terms) will be specially written to be comprehensible to the general reader.

          Scientist to scientist, precise definitions are necessary, and to be expected; scientist to layman, simpler definitions are likely to be necessary; layman to layman, the most basic definitions are likely to be used which can even be totally false and produce no communication of any intellectual meaning (but which may still have different kinds of meaning e.g. the mere act of having spoken to someone could be of emotional meaning).

    • Rational Muslim

      The funny thing is that when Pluto were still considered a planet, it wasn’t the 9th planet from 1979 to 1999, it was the 8th planet since it was closer to the sun than was Neptune due to the crossing paths. Yet when my kids were going to school during that time, they were still taught that Pluto was the 9th planet. Go figure.

      • Angela Zalucha

        its semimajor axis makes it the former 9th planet

        • laurele

          Nothing scientific makes it former. According to the geophysical planet definition, it is the tenth planet from the Sun.

        • Rational Muslim

          According to NASA, it was the 8th planet, not the 9th planet from 1979 to 1999. From the NASA website when responding to its “Starchild Question of the Month for January 1999” when Pluto was still considered a planet:

          “Pluto is usually farthest from the Sun. However, its orbit “crosses” inside of Neptune’s orbit for 20 years out of every 248 years. Pluto last crossed inside Neptune’s orbit on February 7, 1979, and temporarily became the 8th planet from the Sun. Pluto will cross back over Neptune’s orbit again on February 11, 1999 to resume its place as the 9th planet from the Sun for the next 228 years.”

          I trust NASA much more than you since the planetary order was specific to the dates in question.

          • Angela Zalucha

            I don’t doubt that they cross, I was a school child when they did. It’s kind of an “everybody knows that” statement. And your statement is contradictory, NASA pays my salary. I am not some anonymous internet person, I post under my own name, google me.

    • Christian Burgess

      Pluto is a planet, if you remove the water from Earth it is hardly a sphere in fact there is a huge chunk of it missing

      • Alex Leonard

        The depth of the Earth’s oceans is minuscule compared to its overall size (we’re talking a variation of 10km over a planet close to 13,000km across. For all intents and purposes, Earth is extremely round, even factoring in its topographical features.

      • TalkingMoose

        Sorry to dispute your supposition, but if you removed the water from the surface of the earth, it would appear just as spherical as it does now, for all intents and purposes. The oceans, at their deepest, are only about 11km below sea level. The highest point on land is about 9km above sea level. The diameter of the Earth is 12,700km.

    • laurele

      Your analyses are not comparable because the question of Pluto’s planethood is not a question of the data but of an interpretation of the data. In fact, one could argue that the “Pluto isn’t a planet” clique is motivated by sentimentality, specifically the sentiment that our solar system cannot have too many planets. Why the resistance to having a lot of planets if that is what we have?

      Having an elliptical orbit does not preclude an object from being a planet. Many giant exoplanets have orbits around their stars that are far more elliptical than Pluto’s orbit around the Sun. If they aren’t planets, what are they?

      Those of us who continue to view Pluto as a planet do not do so because it’s what we were taught in school. We do so because we adhere to a geophysical planet definition instead of a dynamical one. Many top planetary scientists share this view. We also oppose the notion that a vote by a self-proclaimed “authority” can change the reality of what is out there. That is not science; it’s dogma, and it’s exactly what Copernicus and Galileo opposed.

  • pin head

    Growing up in the 70s I could never grasp why Pluto was even considered as a planet, it seemed to be something that didn’t fit the pattern. Now we know about the Kuiper Belt, it looks pretty clear that we now have a more appropriate class of objects in which to classify it.

    The biggest asteroid and the biggest Kuiper Belt object should no more be classed as planets than the biggest chunk of ice in Saturn’s rings should be classed as a moon.

    • laurele

      But this ignores the fact that Ceres and Pluto are structurally and compositionally very different from the numerous chunks of rocks and ice in their orbits. They are far more like the terrestrial planets than they are like tiny objects shaped only by their chemical bonds. Regardless of location, how is it scientifically accurate to classify objects with geology, weather, differentiation, and all the attributes of the larger planets with tiny shapeless rocks and iceballs?

  • Angela Zalucha

    Ok: as leading Pluto scientist, the facts in this article are true. EXCEPT FOR THE TITLE. There is absolutely no plan to conduct a re-vote. There is a small group of people very passionate about Pluto’s status, mainly in the camp of re-classifying it as a planet. The “Pluto-haters” label is just ridiculous. No planetary scientist “hates” anything. In their scientific reasoning Pluto needed to be re-classified based on new evidence (i.e., this discovery of Pluto-sized objects near Pluto’s orbit). And they happened to “win”. Yes, you could say there was not a quorum and that the vote should hold. So it’s an opinion piece. But you can’t just go stating incorrect facts (i.e., THE TITLE), even in an opinion piece. Most Pluto scientists would rather you ask them something about Pluto (how big is it, how cold is it, what is it made of….) than field the same irritating question over and over and over again. You may think it’s a friendly jest, but I assure you, the reason Pluto was demoted (why do we say demoted? Why is being a dwarf planet a demotion? Is importance in our solar system determined by which world is the biggest?) is very dry, we hate repeating it, and you will either be struck with boredom or laugh and argue with us about it, when we’d rather be telling you that Pluto is neat because we think its atmosphere (yeah, it has an atmosphere!) freezes and sublimates over the course of a Pluto year (248 Earth years, wow!).

    • Feanor22

      You have the coolest avatar pic ever!

      • Angela Zalucha

        I got it as a print from a colleague. It’s about 12 by 24 inches. There’s a larger one hanging in the New Horizons control center in Colorado.

        • laurele

          I sincerely apologize if I offended you in any way, as that was never my intention. Having been at the Pluto Science Conference in 2013, I enjoyed your presentation and respect your knowledge of the subject. I hope we can respectfully agree to disagree on this issue.

          • Angela Zalucha

            My silence is not offense. It is keeping in line with what I said above, that this issue is not of particular interest to me.

            For the record, my degree is in atmospheric science. People like to classify people apparently like they like to classify astronomical bodies. I’ve been tossed into the planetary science category. But I am much more qualified to vote in a resolution about terrestrial climate change than what Pluto is. I would most likely abstain were the vote about Pluto held again, unless both sides made their arguments much much more convincing. Now, enough of my time has been wasted about space policy. I need to debug code that will predict Pluto’s weather over an entire year, something that has not been done before. I’ll get back to you all on the scientific results.

          • laurele

            I just wanted to make sure I didn’t offend you and apologize if I did. I wish you were voting on terrestrial climate change. The Congress we have is a complete circus. Even climate change shouldn’t be subject to a vote–the data is compellingly clear on it.
            I would love to hear your thoughts about the possibility of Pluto and Charon sharing an atmosphere. That would definitely be unique in our solar system (as far as we know, anyway).

          • Angela Zalucha

            Well, now we put ourselves on another tricky slope because how do you define atmosphere? I am very much biased to the lower atmosphere, so anything above the exobase isn’t the atmosphere. (I’m not saying it’s not scientifically important. I just wouldn’t call it the atmosphere,). Stellar occultations of Charon have placed its surface pressure extremely low, nano-barish I think (I’m at home and don’t have access to journals so I can’t give you the number offhand) But by my definition of atmosphere, they most definitely do not share one, unless the calculations from stellar occultations (done by myself and others) and the spectroscopic observations (done by E. Lellouch and others) are grossly underestimated.

    • Kirstin Hendrickson

      Agreed. Though I am not a planetary scientist, I am a scientist, and it’s critical in the scientific community (or in articles purporting to represent science) to be very clear about the difference between fact and opinion. This is a shameful presentation of pure conjecture with a healthy sprinkling of wishful thinking and fantasy (“we will have welcomed them both into our embrace”) as scientific possibility – even scientific likelihood. Planets are not defined by our affection for them or our familiarity with them in space. A bit shocked at the venue for this article; it’s not something I would have expected from Discover. To the author: please, conjecture at will, but make it clear that you are doing so. Perhaps a more appropriate title would have been, “Why I think Pluto should be named a planet once more…and Ceres too.” That clarity, coupled with the accurate facts in the article, would make it worthy of publication in a popular science blog/magazine.

      • Oilcandroid

        Right, but scientists don’t decide what’s fact or what isn’t, since science is really just an informed opinion, at best. Scientific “fact” is only a fact until something comes along and disproves it. Real facts stay constant and science is much more fluid. That being said – I can’t wait to see what Pluto actually looks like! Exciting times, indeed.

        • dj Rogers

          Damn Newton and his informed opinion of gravity.

          • Feanor22

            Yes but his theory was wrong! Well, it was only an approximation of the truth…Relativity includes Newton’s mechanics but extends them to more extreme conditions. Even Relativity is probably incomplete as it fails to account for any quantum effects. So Oilcandroid’s comment is correct: Facts don’t change, but science evolves to understand and model them to more and more accurate degrees.

          • dj Rogers

            Were you the kid in class that never got the joke?

          • Emkay

            never trust an atom, they make up everything…

          • John Rooksby

            Oilcandroid *is* correct, I’m afraid, even if what he or she said seems ridiculous to you. Their perspective is that of the philosopher and philosophers are better at understanding thinking, *epistomology* (the resources and limitations of knowledge), and meaning, than scientists are. Scientists are obligated by the principles of their methods to define things in a very rigid fashion e.g. they should – if they wish to be taken seriously by their peers – utterly dismiss anything that cannot be made to fit the model of their methods. By definition, the truism that their facts are actually mere ‘facts’ (impossible to verify beyond *all* doubt) can only infuriate them.

        • Skip Nordenholz

          Thats why the labelling of Pluto as a planet or not is not really science, you can list a lot of facts about Pluto, but where we choose to draw the dividing line in our how we categorise nature is pretty much arbitrary. Nature is mostly continuims from on state to another. Even the dividing line between stars and planets is grey with brown dwarfs sitting between the two. From the largest star to a the smallest piece of dust, objects at all points in-between are possible.

          • Mitch Robertson

            Someone give this man a beer!

          • Bob Bigellow

            Where we choose to draw the dividing line in how we categorize nature is pretty much arbitrary? In that case, I shall call Pluto a vegetable by tweaking the arbitrary definition of vegetable a bit.

          • Skip Nordenholz

            You could do that and it would not change the science at all, though it would make it more difficult to talk about the science of vegetables, you would have to add a disclaimer to any statement about vegetables to exclude everything like Pluto. We choose categorization dividing lines informed by science to make it easier to talk about scientifically.

      • Mitch Robertson

        Where the facts are ambiguous enough to be objectively uncertain, scientists will quite often fill the factual vacuum with conjecture, opinion, and belief. This subjective (opinion) injection into the objective facts is probably done unconsciously for most – but some would admit that they simply wish to “see” it like this. Regardless, this can become the beginnings of a hypothesis. The flavours of ‘interpretation’ of quantum mechanics (many worlds, etc) come to mind. These exist because the lack of facts in certain areas allow opinion as to where these facts lead. I think you confuse principle over the practice. The varying opinions in fact interpretation (where the ambiguity allows), makes many scientists uncomfortable – but it really shouldn’t. This is integral to the growth of the area in question. A hunch or idea, where compatible with the facts, is a direction to look – a conceptual place to try discover more facts in.

        Your colouring of this article as “shameful” is especially laughable, considering categorisation, as it occurs in science, is very far from the rigidity of the domains of mathematical models. Defining the limits of a word’s definition is often simply the collective ‘decision’ to draw a line in the sand at a particular point.

        • Kirstin Hendrickson

          Unless you are a scientist, you have no business speculating about “what scientists do.”

          • Mitch Robertson

            I’m a computer scientist. Am I allowed now? Now please formulate a reply pertaining to my last paragraph on why I think you’re wrong to call this article shameful.

          • Elaine Meyer

            No, no, you’re really not. Just because computer scientists study technology and use the word “scientist” in their title (do we call it a title if you have a bachelor’s degree?) does not mean they are proponents of the scientific method. If you displayed an understanding of the scientific method, you’d be “allowed” regardless of whether you used the word “scientist” in your name.

          • Mitch Robertson

            Yeah but you claim to be a scientist and you injected nothing more than a load of emotionally charged unfounded vitriol?

          • Emkay

            never trust an atom, they make up everything!

          • Sgt K USMC

            Remember this comment the next time you chose to express an opinion about any group in which you are not an alumni.

            Are you a politician? If not “you have no business speculating about “what politicians do.”

            Are you a member of the armed forces? If not “you have no business speculating about “what military personnel do.”

            Are you a right winger? a left winger? “you have no business speculating about “what right wingers or left wingers do.”

            Are you a person of faith? If not “you have no business speculating about “what people of faith do.”

            In one posted reply you perfectly encapsulated all of the arrogance you seem to believe the sheet of paper on your wall entitles you to, as if science itself is a mystery that is only viewable by those of the “noble clique” to which you belong and all others need to remain seated because, as non-scientists, their opinions are not welcome.

            THAT is what is shameful here… your arrogance.

          • Kirstin Hendrickson

            I do not speculate about what other groups do. There’s a difference between commenting about what a group or member of a group has done and speculating about what they do out of the public view. I can object to the actions of a politician without being a politician. However, without experience in politics and an “insider’s view,” as it were, it would be uneducated and hubristic for me to suggest that politicians, say, make all their decisions while they’re drunk. That would be pure conjecture. Similarly, it’s one thing to say that one objects to a particular study or piece of science, but to suggest that scientists, behind closed doors, fill in their facts with beliefs (etc) is false. It’s ridiculous to suggest that this is what happens, and unless one has firsthand knowledge of it happening (through having experienced it with other scientists behind closed doors (in which case the hypothetical scientists in question would have no place in the broader scientific community), one has no reason to speculate about it. I maintain that it is shameful to present conjecture or wishful thinking (“I hope Pluto is called a planet again”) as fact (“Pluto will probably become a planet”).

          • John Rooksby

            You may be a scientist Kirstin but you’re no expert on English because you’ve completely misinterpreted the writer. Saying ‘I hope Pluto is called a planet again’ is not conjecture. Conjecture is forming a conclusion from incomplete evidence. Nor is ‘Pluto will probably become a planet’ a fact (it is, ironically, conjecture). Moreover, the writer at no point stated as a *fact* that Pluto *will* be re-designated as a planet. His statement that it *will* happen (however certain he feel about this) could ONLY be mere *conjecture* since facts can only be facts once they have been proven (and when the article was written the facts weren’t known). Nor can you claim that the writer intended what he wrote to be *taken as fact* because he very specifically drew attention to the *forthcoming* date until which there could *be* no certainty.

          • Kirstin Hendrickson

            Actually, he didn’t say “I hope Pluto is called a planet again.” He said, “Yesterday, Ceres and Pluto were strangers, distant, barely known runt members of our solar system. By the end of this calendar year, however, we will have showered both objects with our passion and our attention, we will have welcomed them both into our embrace. And we almost certainly will once again call both of them planets.” That is conjecture. “…we almost certainly [anything with incomplete evidence]” is conjecture.

          • John Rooksby

            Kirstin, I did NOT say that the writer said, “I hope Pluto is called a planet again”. I quoted you – that was what *you* said. Here it is again:

            “I maintain that it is shameful to present conjecture or wishful thinking
            (“I hope Pluto is called a planet again”) as fact (“Pluto will probably
            become a planet”).”

            Your reply to me illustrates that you’re still making the same mistake i.e. misunderstanding what is a statement of fact and what is a statement of conjecture. Allow me to explain. You first made this when you cited the statement, ‘Pluto will probably become a planet’ as *a statement of fact*. It is not. It is a statement of conjecture. The single word ‘probably’ is what makes it mere conjecture because this word indicates *uncertainty*; and uncertainty is precisely was a fact is not.

            You have repeated this mistake in saying:

            “To suggest that “we almost certainly will…” is to form a conclusion on the basis of incomplete evidence.”

            “We almost certainly will” is NOT to form a conclusion. You are mistaking it for a conclusion because you’re *failing to factor* the words ‘almost certainly’ into the meaning. These words, as was the case with the word ‘probably’, indicate the writer’s *lack of* certainty. ‘Almost certainly’, ‘probably’, ‘surely’, ‘might’, ‘could’, ‘should’ – all these words (and there are plenty more) indicate a lack of certainty.

            That the Pluto scholar also misunderstood the writer only goes to prove that scientists can be mistaken (shock, horror!) and arrogant (shock, horror!) – capable of thinking that their expertise in one field enables them to be equally certain of themselves in others, in this case, English language.

          • Marc Sainte-Marie

            HA HA What a scientist Kristin is. Though I am not a scientist, it’s critical in the non scientific community to be very clear about the difference between said facts and opinion. That was a shameful misinterpretation of pure misdirection with a healthy sprinkling of wishful thinking and fantasy. Woe to the world with such priestess for Science!
            (jeez imagine with complicated scientific stuff what she dishes out, hope not medical as one doc took out my useless evo tonsils… at least I still have my junk DNA)

          • bromo33333

            You are correct that the prediction isn’t very good. And since the reclassification was almost a political process (voting), the exact facts might not be that important about what they find about Ceres.

          • NanuNanu

            Apparently, aliens don’t bother with the planet, dwarf planet, asteroid classifications, they just call them satellites and the apply useful dimensions like orbital distance/path, weight & composition & habitability…seems sensible to me. Apparently, or anal retentiveness is a bit of a joke, reading this thread, I can see why but please don’t stop, it brings levity and helps pass the interstellar hours… 😉

          • asdf

            This is amazing, and now for the big question…
            Do aliens poop?

            Can’t wait to hear more about this from someone who knows what aliens call planets.
            Also massively fascinating that aliens speak english…

            You would think they call planets “blarghs” or something like that 😛

          • Elaine Meyer

            Conjecture = drawing a conclusion from incomplete evidence, per your own words. Kirstin pointed out, correctly, that the author drew a conclusion (“we almost certainly will once again call both of them planets”) from not just incomplete, but nonexistent evidence. The author was not expressing a hope as such; he was expressing a hope as a near-certainty, which is fine in a lay-blog, but nearly unforgivable in a medium that advertises itself as passingly scientific. Kirstin, you’re absolutely right on here; this has no business in a scientific forum. That said, the comments are, in large part, an indication of the sort of audience to which the magazine apparently panders; it appears there is no place for real scientific discussion here.

          • John Rooksby


          • Thomas

            you are entirely correct.

          • bromo33333

            “we almost certainly will once again call both of them planets” isn’t conjecture, it’s prediction.

            “almost certainly” is the words that take it from ‘conjecture’ and throws it into ‘prediction’

          • laurele

            How is it any different when Mike Brown claims he “killed” Pluto and tries to leverage that into money and fame? He has repeatedly stated that as long as he is alive, Pluto will never be a planet again. Is that science or wishful thinking?

          • bromo33333

            That’s a taxonomist with an ego the size of Pluto. Changing classifications, and then showing off about it, is hardly what I’d want to hang my hat on as a scientist – but if he wants to be one of the folks that are famous for being famous rather than accomplishing something real, the world these days are filled with that type.

          • Vatnos

            He discovered quite a few dwarf planets, including Eris. That’s pretty immortalizing.

          • asdf

            Yea, finding one of UNLIMITED planets, makes you SOOOOO immortal…
            I know more people that collected stars in Super Mario Galaxy then i know names of people that discovered stars or planets in the real world…

            Seriously, i can’t even remember the name without looking up… Looking further up… well… screw that guy… can’t be bothered to scroll up to look at his name… THAT is how immortal that idiot is 😛

            Shoutout to Arin Hanson and Daniel U Sexbang for their amazing Super Mario Galaxy Playthrough!
            That’s what EEEEEYEEEE call immortal *wink*

            Btw, gotta look up Eris now… you sound like it’s something important and i have NEVER heard of it…

          • Johannes Wiberg

            I read Mike Brown’s book and I didn’t take that from it at all. I saw the title as a joke based on media’s overdone take on the issue. In the book he actually laments Pluto’s “demotion” – although he also argues that there’s nothing wrong with being a non-planet, and that we should use the nomenclature that fits facts the best.

          • Emkay

            Pluto, the goofy dog at DisneyWorld does not care…but thanks for your effort..

          • Weston Chambers

            Pluto is a mutt. Goofy is a dog.

          • Stahl Helme

            So is that conjecture, supposition, speculation, prediction or fact? Forgive me, I don’t have a scientist card and get confused..which one was Mickeys best friend?

          • Emkay

            READ ABOVE….

          • asdf

            Actually the goofy dog is Goofy, Pluto isn’t funny at all, thank you very much! ^^

          • Emkay



            Goofy is a funny animal cartoon character created in 1932 at Walt Disney Productions. Goofy is a tall, anthropomorphic dog, and typically wears a turtle neck and vest, with pants, shoes, white gloves, and a tall hat originally designed as a rumpled fedora. Goofy is a close friend of Mickey Mouse and Donald Duck and is one of Disney’s most popular characters. He is normally characterized as extremely clumsy and dimwitted, yet this interpretation isn’t always definitive; occasionally Goofy is shown as intuitive and clever, albeit in his own unique, eccentric way.

            Pluto, also called Pluto the Pup,[1] is a cartoon character created in 1930 by Walt Disney Productions. He is a yellow orange-color, medium-sized, short-haired dog with black ears. Unlike most Disney characters, Pluto is not anthropomorphic beyond some characteristics such as facial expression, though he did speak for a short portion of his history.[2] He is Mickey Mouse’s pet. Officially a mixed-breed dog,[3] he made his debut as a bloodhound in the Mickey Mouse cartoon The Chain Gang.[4] Together with Mickey Mouse, Minnie Mouse, Donald Duck, Daisy Duck, and Goofy, Pluto is one of the “Sensational Six”—the biggest stars in the Disney universe.[5] Though all six are non-human animals, Pluto alone is not dressed as a human

          • asdf

            Do you even Space Disney?

          • Emkay

            of course….

          • Sgt K USMC

            Speculation is the bread and butter of science, and yes, it is perfectly acceptable to speculate on the motives and personal opinions of those who make decisions worthy of discussion in the public eye. Because like it or not, BIAS is a factor in all science, hell, in all walks of life.

          • bromo33333

            Except the act of labelling and label changing is a political process (voting) not one of scientific discovery.

            But also saying that scientists are the only ones that can have opinions on scientists might be true in the sense that firefighters have the most valid opinions on firefighters … it is a useless definition and restrictions. It’s more used to shut down argument, than encourage understanding and discovery.

            I’d love for Pluto be be labelled once again as a planet. Any of these classifications are arbitrary in nature (with a rationale), and you can change the label and rationale at any time. The labels help people understand their world, but in no way change the objects themselves. A scientist wouldn’t be deterred, but it might influence the general population’s perception unduly.

          • ISDAMan

            You speculated that he speculated without any direct knowledge of his direct knowledge or possibility of greater knowledge than your own. As such, you cast aspersions upon his potential for being qualified to speak on the matter. You speculate.

          • gth

            You don’t have to work in the specific field to have an informed opinion on that subject matter and to suggest otherwise is obtuse.

          • Jonathan Wallace

            How can you call yourself a scientist when you are guilty of propagating unscientific logical fallacies? This is tragically ironic.

          • Gemini

            Well considering No Scientist has ever been to Pluto, everything said about Pluto is an assumption not a fact.

          • Francisco Salinas

            Wrong … it is a fact that Pluto exists .. a fact that Pluto is far away … a fact that Pluto was discovered by Clyde Tombaugh … a fact that Pluto has satellites … fact … well there are hundreds of facts we know about Pluto …

          • Francisco Salinas

            Yadunnonuttin’ … Gemini

          • Elaine Meyer

            You must be kidding. She was not speculating about what members of any other group do, she was only saying NOT to speculate about what members of a group of which one is not an alumnus do behind closed doors. Actually, I am also a scientist and I also take offense at the notion that anyone could possibly think we supplement fact with belief. This article is ridiculous, unscientific in the extreme, and a frank example of a click-bait title.

          • Sgt K USMC

            Correct me if I am wrong here but is it not speculation itself that drives the search for answers?

            Now… as to your example.

            If I were to explain to you that your thinking on the topic of Marine tactics was “shameful” as opposed to either correcting your misinterpretation or offering you facts on the matter, and then further explained to you that you have no right to think the way you do… well then… that goes down a different alley altogether.

            Telling a person they have no right to “think” a certain thing about a certain group because they are not a part of that group, it is arrogant, it is also a perfect example of counter-intuitive reasoning.

          • Emkay

            ‘counter-intuitive reasoning’.. isn’t that kind of like holding a small mirror in one hand in front of your large mirror in your bathroom, while singing an old nursery rhyme?…

          • Neville

            This is a wasted opportunity. We have intelligent people winding around in tight little circles about grammar and context. Let’s try to talk less about nothing and more about something, maybe we’ll get somewhere. Are there any other spherical objects in our solar system that may qualify? Titan doesn’t orbit around the sun so it’s out, but isn’t it way larger than ceres? If you had the opportunity to propose what the definition of what makes a planet a planet, what would you propose? Would you also have a dwarf planet definition? Why, why not? If yes than what?

          • James38

            You got that one right, Sgt K. (and thanks for your service).

            I am a scientist, by virtue of many years of study, lately in the fields of energy and climate change.

            However, I hold no official degree, and may thus qualify for scorn from ol’ Kirstin. But maybe it isn’t arrogance, maybe it is just rigidity, stemming from that titanium rod she appears to have sat on.

            Methinks she protests too much.

          • Emkay

            so the naming of planets devolves to name calling and colo-rectal insertions… nice…

          • Muawiyah

            Geology magazine about 6 years back revealed that with space radar it is possible to penetrate 30 clicks into Earth’s crust ~

            That undoubtedly being way short of today’s space radar range, it is possible that we can see clean plum through our own planet and check out anyone’s colo-rectal regions without a great deal of difficulty from any point.

          • Francisco Salinas

            Any colo-rectal insertion volunteers?

          • bromo33333

            Keep in mind the classification was *voted* upon, which is a political process, not a scientific one.

          • Kathleen8523

            Fill up your pay pal account with money fast while freelancing at home… Check it out

          • Francisco Salinas

            Will you folk stop using 500 dollar words and come back to tierra¿

          • Rip Vanden Broecke

            You’re right on the mark Sarge!
            I believe it is the sole reason why far too many non-scientific members of society seem to have a hard time believing in many of sciences doctrines like evolution and paleontology and even astronomy just to name the most widely discredited amongst the non-scientific populace.
            It is this kind of snobbery that cause idiotic pronouncements by politicians and other notorieties like “I don’t believe in evolution”.
            They aren’t scientists either, but they have a lot more sway on the general populations attitudes and perceptions and it is counterproductive to the scientific efforts of the search for truth and the enlightenment of the masses.
            I too am not a scientist, but not by choice nor capability. Unfortunately if you come from a poor family, in a rural setting far from any educational institutions that provided this level of education, it was pretty nearly out of the question, as was my situation. But that didn’t stop me from pursuing my scientific interest personally as best as I could.
            So just because some of us didn’t get the opportunity to acquire that “sheet of paper on your wall” as Sgt K so accurately put it, doesn’t mean our opinions should be cast aside as rubbish, nor does it give anyone the right to tell another to basically “shut up”.
            I think if all scientists had or have attitudes like that it will forever be an uphill battle to convince the non-scientific community to listen to you and therefore, understand the truth and the benefit of your research.

          • David J

            whatever. I don’t need to be a monkey to know what monkeys do

          • sivakumar Srinivasan

            No one is a born scientist , newton , Einstein don’t HV PhD degree but they did something that is impossible for the so called current scientist to even imagine , more everever Pluto is a planet or not is of no real scientific significance to any one

          • bromo33333

            LOL. Like filling the vacuum of facts with opinion and conjecture? Scientists are human, too. I think trying to disallow someone their stated opinion is wrongheaded, though I do think that Mitch was out of line.

            Removing the emotion and insult from his post, there remains a grain of truth, but where he got it wrong, is the opinion, conjecture are usually based upon something, and have a category of “hypothesis,” no? Then you perform tests to see if the hypothesis holds.

            Having said all of that, I thought it was disappointing that Pluto was recategorized – I have had a soft spot for the PLANET Pluto. I figure the status of Pluto, Ceres and other small planet-like objects form the dividing line in which people want to have taxonomy like classification. You have to draw the line *somewhere* with some justification – especially when there appears to be a spectrum of characteristics and sizes. You could narrow up the definition of planet to only include the so-called “gas giants” and make the rest of the object “dwarf planets” if you like, too.

            I guess what I am saying is that the definition might have a rationale behind it, it still feels somewhat arbitrary and like taxonomy.

          • bromo33333

            While I thought Mitch was out of line, I think your retort was just as out of line. Disallowing an opinion with your rationale would remove your ability to hold opinions about most things in the world. I suggest you revisit your comments.

            Having said that, ultimately the taxonomic classification of Pluto as a planet was *voted* upon, which is more of a political process than a scientific one. And while taxonomy is a scientific pursuit, it involves drawing arbitrary lines based upon principles that are decided upon to force categorization and bestow labels on things.

            We could have had equally valid classifications that Earth is the only planet (define “planet” as something that has sentient life upon it), or only the Gas Giants (Only planets are those larger the Neptune, not supporting fusion), or only everything BUT the Gas Giants (only rocky cores, and thinner atmospheres/vacuum than the gas giants) — all would be valid and have a rationale but in the end is a political decision (voted upon), and an exercise more in labelling than one of scientific discovery.

            My opinion on the subject is that the body decided to over-classify things to force “change” when none was needed. It was a political process (voting), not a scientific one.

            They could have waited to see where Ceres fell and then revisited it all with more knowledge. It’s possible they could have.

          • ISDAMan

            You’re not allowed to talk? That’s the best you can do? No salient rebuttal? If you had any manner of cogency from which to draw upon, you would have done so. If you truly are a scientist while concomitantly refusing to hear someone out because they are not vetted to your liking, you only prove yourself to be an egotistical self-deluded fool.

          • Astute, Ph.D.

            That’s arrogant, condescending, and just rediculous. Everyone has a right to their opinion, and science is subject to review from any source. If the science can’t take the review, it should not have been published.

          • Jim

            An “astute Ph.D” who doesn’t know how to spell ‘ridiculous’…

          • Jim

            An “astute Ph.D” who doesn’t know how to spell ‘ridiculous’…

          • Jonathan Wallace

            Classic appeal to authority logical fallacy straight from an arrogant closed mind. You may call that an ad hominem logical fallacy but I think you will still agree!

          • TheEdgeofMind.

            This was your jumping the shark moment.

            Maybe you forgot about the atom bomb and how that impacted everyone’s life on the planet.

            Your frame of mind is scary and dangerous and titters on fascism and close mindedness.

            By stating “Unless you are a scientist, you have no business speculating about “what scientists do.””

            You are drawing a line on public opinion. Remember space exploration is a humanity effort collectively and mostly funded by tax payers who fund space exploration. Pandering to speculation helps draw in the public’s attention. This is why private space programs with out public tax money will fail. Compare the budget of the moon program in the 1960’s and spacex’s budget. The public funded moon program in the 60’s dwarfs spacex budget by a whole lot. I am sure you can look at the facts your self. JPL and NASA both publicly funded are doing way more then any privately funded endeavor. Without the public using its imagination about what scientists do there would be no more future scientists and no public money in those projects. Which in turn means no more space exploration.

            Good day.

          • Francisco Salinas

            blah blah child’s talk

          • asdf

            Unless you are a robot, you have no business speculatin about “what robots do”…
            Are you serious? Since WHEN do people give orders to themselves?
            I can ASSURE you that scientists are NOT payed and ordered around by scientists. Every 6 year old rich kid can even COMMAND “what scientists do”

            How do retarded comments like this get 200 upvotes? Are there SO many idiots around or are you just upvoting yourself with next gen NASA tech?

        • Angela Zalucha

          Both sides of the Pluto debate are much more solid than quantum mechanics and many worlds. While I can see both sides of the Pluto debate, the definition of a planet is based on very observable quantities. If anything the pro-planet side fills in the factual vacuum (e.g., by hypothesizing that Pluto’s interior is differentiated). Even that is classical mechanics, hundreds of years old.

          • Mitch Robertson

            Could the earth “clear its neighbourhood” in the Kuiper Belt or not? If that is one of the considerations of the definition of a planet or not?

          • Angela Zalucha

            To the first question I don’t know the answer. But insofar as planet definitions, the body in question has to have cleared its own neighborhood, not some reference neighborhood of x number of objects at y distance or something.

          • Mitch Robertson

            Well I think the point of asking whether the earth would clear pluto’s neighbourhood is more to highlight that the neighbourhood-clearing restriction of the proposed planet’s definition cannot be an objective one – and therefore unsuitable for consideration on planetary status. This critique holds whether the earth was or was not massive enough to sweep up its orbital path.

          • Angela Zalucha

            These are points that pro-planet people bring up, and I agree they are valid points. But how do you make it testable? In planetary science (not just orbital dynamics, but geophysics, atmospheric physics…) celestial objects aren’t lying around for us to do test on. So then you have to rely on computer models. Sometimes these are testable (weather forecast model). Sometimes these aren’t, realistically (we don’t have 0.5 billion years). So where do you draw the line between models and observables? FYI I’m a computer modeler.

          • Mitch Robertson

            Good point. I think I meant more that the definition has to be boxed in – regardless of whether it could be tested yet. Unfortunately that would give every object orbiting a star “planet-pending’ status haha.

          • Old_ones

            Of course it is objective. The number of satellites orbiting in a particular region of the solar system is an observable quantity. Whether the distribution of matter in the solar system is more or less important than the mass of an object for “clearing its neighborhood” is more ambiguous, but also kind of irrelevant.

            Its important to understand that the debate over whether Pluto is a planet is a debate about arbitrary labels. Categories like “planet” and “dwarf planet” are a matter of convenience more than rigorous statements about reality. If planetary scientists felt that only gas giants should be considered true planets, and decided that terrestrial planets should be considered “pseudo-planets”, our annoyance at no longer living on a “planet” wouldn’t be a rebuttal to that. The nature of Pluto doesn’t change just because we came up with a new name to call it.

          • Mitch Robertson

            No one is claiming that the number of objects orbiting a star is a subjective fact? I then proceed to agree 100% with your second paragraph. Yes its arbitrary label land – not objective science land. Not every word that comes out of a scientist’s mouth is science.

          • Old_ones

            I was talking about the “neighborhood clearing” distinction. We can see whether an object has cleared its neighborhood, therefore “neighborhood clearance” is an objective standard. We can’t directly tell what size pluto would need to be in order to have cleared its neighborhood as far as I know, but I find that irrelevant.

          • Mitch Robertson

            Not really. Even if you could see all the impacts on a planet, its pretty hard to work out how many other objects that it simply ejected. As far as I can see, there is no way to tell what the orbital path of a planet used to look like unless you have a time machine.

          • zed james

            I think you’ve just made an ill formed argument here about “neighborhood clearing”. Your question “Could the earth “clear its neighborhood” in the Kuiper Belt or not?” it’s not a valid question. I could ask you something like: Could you be Lady Gaga or not? In both cases there is no answer. Earth can’t be in the Kuiper belt clearing other planetoids because it wouldn’t be the Earth as we know it. It would be something else. Maybe a bigger planet or an agglomeration of small asteroids, depending on the circumstances. On the other hand you and Lady Gaga are both humans, neither can be the other, you have to be “born that way” to be her. Therefore clearing it’s neighborhood seems a quite valid prerequisite.

          • laurele

            On multiple occasions, exoplanets have been found in orbits where they were supposed to be unable to exist. I would not rule out the possibility of an Earth-sized planet in the Kuiper Belt. Some astronomers believe one or two such planets still remain undiscovered as far away as the Oort Cloud.

          • Mitch Robertson

            I’ll take your point about can earth clear another planets orbit not being a valid question. That doesn’t take away my criticisms of orbit-clearing in general being quantifiable enough to include into a definition.

          • visibleunderwater

            I cleared out my closet, does that make me a bedroom planet?

          • James38

            Whoa, wait a minnit. You say “This critique holds whether the earth was or was not massive enough to sweep up Pluto’s orbital path.”

            But if Earth is to be set on the task of “sweeping up” Pluto’s orbital path, does that mean it would have to sweep up Neptune? We need to look at what Jimbow said: “Correct me if i am wrong since Pluto crosses Neptune’s orbit then Neptune did not clear Pluto out of it’s neighborhood so is Neptune a planet?”

            Well, obviously maybe not. But If Earth can’t gobble up Neptune, and Neptune fails to gobble up Earth as it failed to snarf Pluto, we have a real question on our hands.

            If Neptune isn’t a planet (by the “sweep up” standard), maybe there aren’t ANY planets in the solar system. I mean, really, SCIENTIFICALLY, if Neptune ain’t a planet, what is?

          • 7eggert

            Maybe I can ask a better question: What is the “neighborhood”? What is “clearing”? Is Neptune a “Dwarf planet” because it didn’t clear Pluto out of it’s orbit?

          • Angela Zalucha

            neighborhood is what it has gravitational influence on, and clearing means it isn’t going to be smacking into anything (well, besides dust maybe). Neptune doesn’t count because it is in a 3:2 resonance with Pluto. For every 3 times Neptune orbits the Sun, Pluto orbits twice. Today’s factoid: they will never collide because of this

          • 7eggert

            So if you can’t (don’t, for early systems) clean, it’s not your neighborhood? Then anything that’s not about to be smashed is a planet.

          • Angela Zalucha

            It’s your neighborhood if you have gravitational influence. So presumably neighborhoods could overlap, such as, the asteroid belt.

          • John Rooksby

            Most things (and possibly *everything*) in the universe has a gravitational affect upon everything else, however minute. At once the concept of the ‘neighbourhood’ requires a more precise definition than the one you have stated. Is there such a precise defintion? If there is, can it be applied equally in all situations? I doubt it. What we have here is a crossing of paths of science and *philosophy*; and while these fields often cross it is rarely the case that scientists are also philosophers (much less equally good ones) and vice versa. Being more of a philosopher than a scientist myself, I would suggest (as Old_ones did to some extent) that the scientists try to remember that we classify things, give them names, in order to talk about them meaningfully to one another. Considering that whether we understand one another’s definitions in the same way is *always open to question*, I think the most important thing is not what scientists, arguing between themselves, think is a planet or not but what the ignorant general public thinks because the word ‘planet’ is more for their benefit than it is for yours (because they far outnumber you and you i.e. scientists, tend, on the whole, to consider your purpose to be to bring enlightenment to the species. It’s no good to the species for the scientists to define things so accurately that they can no longer be understood by those for whom they work. This article was written for a wider audience than the cosmologists of the world. What is indisputable is that the definition of the word ‘planet’ is vague and imprecise *among scientists* YET this hasn’t mattered one iota so far – hence the matter has been left inexact. It’s ironic actually that the only people who *are* bothered about the definition of the word ‘planet’, and who *are* arguing about it, are the very people who know the most and hence should be in the least doubt!

          • 7eggert

            What is gravitational influence? Jupiter has gravitational influence on Mercury and would kick it out if it wasn’t for Earth. It didn’t … not a planet?

            Or do we define the influence as “does kick out things in it’s path”? Then everything that cleared it’s narrow path would qualify. (And for Neptune’s sake, we don’t even count non-colliding objects crossing it’s path).

          • Valentino Pintus

            You should consider that with Neptune’s size is way bigger than Pluto. It would be a pretty strong impact but Neptune would surely survive.
            That is the definitione of having cleared its neighborhood. When no other corp around you can smash you into pieces than you get the status of planet.

          • laurele

            According to Dr. Alan Stern, who did the necessary calculations, Earth would not clear its orbit if it were in Pluto’s location.

          • Rip Vanden Broecke

            But has Earth or for that matter any of the other “planet” truly cleared it’s neighbourhood? If so, could you enlighten me as to what that means? To me it would mean that the planet in question no longer gets bombarded by other celestial objects such as meteors or comets. If that is the case than why do all the planets still get this bombardment on quite a regular frequency? Is there a some guide line as to how many times a non-planet must be hit to be eliminated from it’s planetary status? If so, could someone enlighten me to those statistics? Or is it because Ceres resides within an asteroid belt and Pluto at times resides with the Kuiper Belt during it’s orbit, is that the definition of “clearing it’s neighbourhood”? Then Earth, which yearly goes through several minor asteroid belts [Perseids, Draconids, Leonids, etc…] to produce the annual meteor showers, by those standards should also lose it’s planetary status, no? There was resentment by one of the scientists commenting here that some were being referred to as “Pluto haters” although you may not be Pluto haters, all those that believe that a “dwarf planet” isn’t really a planet most certainly sound like Pluto bigots. Perhaps by this scientific reasoning we should stop considering dwarf people as real people too. Really, aren’t there more important astronomical events to argue over than whether or not Pluto or Ceres is or is not a planet?

          • Angela Zalucha

            You are very keen with your questions and spot on with “Really, aren’t there more important astronomical events to argue over than whether or not Pluto or Ceres is or is not a planet?” YES. YES. YES. That is exactly my take on things.

            I am not sure what the precise definition of “clearing your neighborhood” is. That is one of the arguments that pro-planet people point out.

          • dsfportree

            Earth hasn’t cleared its neighborhood. That’s why we have near-Earth asteroids. In fact, all planets are dwarf planets, since none has cleared its neighborhood.

            Never mind extrasolar planets – the IAU definition doesn’t admit them.

            “Planet” has been a cultural label for a lot longer than it has been a scientific one. Scientists co-opted it a few centuries ago, but for thousands of years before that planet meant a wanderer in the skies of Earth and a metaphysical entity.

            So, lots of problems with the current discussion.

            I suggest we call everything that isn’t a star a “world” and create subdivisions within that based on the need for planetary scientists to communicate clearly with each other. Much as has been done in the field of biology, for example.

            A subset of bodies that fall under label “world” can be the “classical planets,” a cultural label, which could include Pluto (whether Mike Brown likes it or not). Much as mere mortals refer to a “cow” as a “cow” and a “dog” as a “dog” and biologists use a more complex definition that aids them in their work.

            Scientists can develop meaningful labels for different kinds of worlds based on their inherent characteristics. Worlds for which we lack data can be called worlds and left at that – the label in that instance posing a challenge to the scientist to develop a meaningful classification through acquisition of new data and scientific debate.

            Science educators can use this as a broad teaching opportunity, since it admits culture and specific, meaningful definitions for types of worlds.


          • John Rooksby

            Excellent contribution, dsfportree.

          • Rational Muslim

            FROM THE NASA WEBSITE: “And third, it must have cleared other objects out of the way in its orbital neighborhood. To clear an orbit, a planet must be big enough to pull neighboring objects into the planet itself or sling-shot them around the planet and shoot them off into outer space.”

            Earth has done exactly that. The moon is within the Earth’s orbit while the asteroids all are sling-shot out into outer space whenever they come close (or they end up hitting Earth with relatively little damage as far as Earth is concerned — though they can cause considerable damage to LIFE on Earth, just ask the dinosaurs).

          • laurele

            There is no one “the” definition of a planet.There are currently multiple definitions of the term planet in use, each of which is scientifically sound.

          • Nem

            Yes there is a one “THE” definition. It happened in 2006, just because you might not like the definition doesn’t mean that it isn’t the one that is used.

          • laurele

            Really? What you are describing is dogma, not science, more characteristic of a church than an organization of scientists. The fact remains there are several definitions of planet currently in use by planetary scientists. Just because you don’t like their definitions does not mean they are not legitimate.

          • disqusaurus_rex

            The problem with the characterization of the planet by certain observable qualities (rather than quantities), is that the qualities chosen seem to have been fairly arbitrarily chosen to solve the uncomfortable problem of “we wouldn’t know how many planets our solar system has.”

            This is particularly true of the “orbit clearing” criterion, which the potential super-Earth at 700 AU might not meet (for at that distance, what could?) The notion that this body could not survive the planetary test, where small Mercury and Mars could would end up bringing the whole exercise into disrepute.

        • laurele

          If there are varying interpretations of an issue, why should one interpretation be given privileged status over all others?

          • Mitch Robertson

            I agree. I say let the controversy continue! I just objected to calls that this article is “shameful” and that the scientists discussions on the planet definition was hard science.

          • John Rooksby

            That’s a matter of philosophy, Laurele. Who here is an expert in philosophy (and if there is such a person, a) Would the others in the discussion agree to accept a philosopher’s expertise in the business of thinking, ascribing meaning, and its value here? and b) Would that philosopher be up to the particular task in question given that the discipline has four main branches not all of which pertain to this problem? Now I happen to be a philosopher and I would suggest trying to consider the elements under discussion as being either facts or opinions. I would also STRONGLY suggest avoiding a descent into an argument about the definition of a fact (we struggle with these questions so more immediately useful people don’t have to) or you’ll never get anywhere.
            Assuming no one here is a troll looking only to play silly buggers, we can should all be able to agree on our facts. The definition of an ‘opinion’ is, ‘A belief in the absence of facts’.

        • Mark Poepsel

          You’re demonstrating a fundamental misunderstanding of science. It’s apparently willful. You talk about science as though there are complete chunks of knowledge out there for us to grasp and then holes or “vacuums” out there that scientists fill with conjecture. That isn’t how it works. You can claim so but that’s not factually how the hundreds of thousands of scientists (professional and amateur) in the world approach it. There is a tendency to extrapolate from fact and to make new hypotheses, but when they’re stated as such they’re part of the process not filler as you would describe.

        • localvagrant

          It’s shameful because the article’s certainty is misplaced – this article is a huge non sequitur. Let’s have an honest conversation on Pluto’s planethood, not wishful thinking woo-fests like this.

      • Emkay

        oh please, Pluto is a big goofy dog at DisneyWorld… get over yourself.. we don’t care if you call him a planet or not.. it DOES NOT MATTER….

      • Clint Henry Utiripse

        Like you guys dont even contribute to real earth problems lols..Would have been great if you can prove your theories but you cant. In fact i think you guys just sit there and make up stories and pass it as scientific fact. In the hierarchy or scientists you are the lowest. You are just as scientific as a science fiction writer. Dont be proud of yourselves. now tell me how will we benefit from the information you got about space? Will it cure cancer? Solve global warming? feed the hungry? Cure diseases? No!

    • Jacon

      I agree totally. The article viewpoint is silly. Did realizing that Earth orbits Sol rather than the other way around amount to a demotion for Earth? This author would seem to think so.

      • celebrate logic

        Well, the Catholic Church sure seemed to think it was a demotion. In fact they were pretty mad about it, much more so than any ‘Pluto is a planet’ fanatics.

        • Emkay

          so, now the church is in it! does anyone really care what an object that is a half billion miles away is called..seriously.. who cares..

        • Webster

          They didn’t, really. In fact, cathedrals all over Europe were used as solar observatories to advance our understanding of the relationship between the sun and the earth.

    • The Man

      So how do you respond to the location argument? If you put Earth in either Ceres or Pluto’s location it wouldn’t be able to “clear its neighborhood” either. Location shouldn’t matter.

      • Old_ones

        Why shouldn’t location matter? Its an observable difference. Also, you don’t know that Earth wouldn’t clear its neighborhood if it was located in the Kuiper belt. That’s a speculation, not a fact.

        • Angela Zalucha

          I’m not sure about whether or not Earth could clear Ceres or Pluto’s orbit (that doesn’t mean someone doesn’t know, probably someone does, but I’m an atmospheric scientist). The location bit is tricky because it assumes that solar systems follow the same model (rocky inner planets, gas giant outer planets) and all the stuff floating around in between. When other solar systems were discovered they had a completely different configuration and everyone scratched their heads

        • Kerberos

          But the Earth did clear it’s own neighborhood. The early solar system was all a big swirling disc of rocks and gas. Some rocks got bigger and bigger colliding together, more mass giving more gravity (and pulling the whole thing into a sphere – one requirement to be at least a dwarf planet over an asteroid) and attracting more and more, growing into the planets as they clear out their neighborhood, at least for the most part. There’s still stuff out there, but not to the extent of the Asteroid Belt or Kuiper Belt. It was probably Jupiter’s gravity that kept the Asteroid Belt from grouping up into a single planet with a cleared neighborhood, pulling everything out a bit as it passed by. Also, Pluto is not the largest member of the Kuiper Belt as stated in the article, the dwarf planet Eris is larger.

          • laurele

            No, actually Eris is not larger than Pluto. It was initially thought to be so, but in November 2010, a team of astronomers led by Dr. Bruno Sicardy obtained a more accurate measurement of Eris when it occulted a star, and determined it is marginally smaller than Pluto though 27 percent more massive. More massive means more rocky and therefore more planet-like.

          • chopshopstore


          • Webster

            Rocks don’t stick together. They bounce.

        • The Man

          The Kuiper Belt is about 20 AU, so you’re telling me if you took a planet as relatively small as the Earth you think that it could clear the Kuiper Belt even though it can’t clear the Asteroid Belt that’s about 1.3 and 2.3 AU away from it?

          • Old_ones

            No, I’m saying I don’t think that fact is known. It doesn’t really matter what I think, it matters that Earth isn’t embedded in a “belt” of bodies.

          • laurele

            What an object inherently is should be more important to its classification than whether or not it is embedded in a belt of objects. Being embedded in a belt of objects much smaller than itself does not in any way change the initial object.

        • John Rooksby

          I agree with you Old_ones. Location certainly does matter because the most widely understood definition of the word ‘planet’ is in part down to the most widely understood definition of the word ‘moon’ i.e. planets orbit stars and moons orbit planets (hence planets are not moons nor vice versa). However, if one were to relocate the Earth next to a much bigger planet, the Earth could fall into orbit around that planet and consequently become a moon, a satelite. The writer opined that the Earth, in such a situation, must still be considered a planet *because most people would object* to scientists changing the designation of the Earth but I would argue that this wouldn’t make any difference to scientists; and it certainly wouldn’t make any difference to the facts. The scientific method demands that everyone gets in step with what science dictates and not the other way around. Copernicus didn’t care that most people weren’t happy to hear that the Earth revolved around the sun and not the other way round; and in short order the people aligned themselves with the truth. However, the writer of the article was VERY CLEAR in saying that this ws just his *opinion*.

      • 7eggert

        Location does matter for Titan.

        • sadoul1

          Can you imagine reclassifying Saturn as a binary system?!

          • 7eggert

            Not while keeping a straight face. My Avatar isn’t supposed to be a self-portrait.

        • laurele

          Actually, Titan is considered a secondary or satellite planet by adherents of the geophysical planet definition. According to this definition, a planet is a non-self-luminous spheroidal body orbiting a star, free floating in space, or even orbiting another planet. If the object isn’t a star itself and is large enough and massive enough to be squeezed into a round or nearly round shape by its own gravity, it is a planet. This definition classifies objects first and foremost by their intrinsic properties rather than by their locations. Titan has most of the same processes and complexity that terrestrial planets have; it just happens to be orbiting another planet instead of orbiting the Sun directly. Calling Titan a satellite planet does not make Saturn-Titan a binary planet system because the barycenter, or center of gravity between the two objects is inside Saturn, unlike Pluto-Charon, where the barycenter resides outside of Pluto and between the two bodies.

    • nono

      You are clearly not any form of Scientist. Else you would have educated enough to know when one should use “i.e.” vs “e.g.”

      • Angela Zalucha


        • Webster

          In your initial post, you said:

          > But you can’t just go stating incorrect
          > facts (i.e., THE TITLE), even in an
          > opinion piece.

          What nono was saying is that the “i.e.” there is incorrect. The abbreviation “i.e.” stands for “id est”, Latin for “that is”, while “e.g.” stands for “exempli gratia”, Latin for “for example”. This part is probably correct: you referred to “facts”, which is plural, then identified one, which is singular, so they can’t be the same, and “i.e.” is wrong.

          The post also said that any scientist should be well-educated enough not to make this mistake. Here I think nono overreaches. And is maybe joking.

      • Robert

        CLEARLY, you don’t know that ANGELA ZALUCHA is a Spanish name and that E.G. is I.E. in SPANISH.

        • Webster

          Um, no.

          Even if it were a Spanish name, that would not mean you could assume she speaks that language.

          But it’s not. It appears to be Russian.

          And the equivalent of “e.g.” in Spanish is not “i.e.”, but “p.e.” or “p.ej.” for “por ejemplo”.

          So, strike three, yer outta here!

          • Robert

            You might want to GOOGLE that, genius. A first grader could do that…. and find the answer.

          • Webster

            That’s what I did, to add detail to my existing background knowledge of the matter. So, you’re wrong again. Don’t bother replying unless you have some actual data to back you up, and are willing to cite your source(s).

          • Robert

            Google “ie stands for”. Beware you will have to stand corrected and eat crow.

    • visibleunderwater

      admit it, you hate Pluto!

    • Skip Nordenholz

      I don’t think anybody has taken the “Pluto-haters” seriously, I think everybody understands its a joke.

      • laurele

        More accurately, they hate the idea of our solar system having what they consider to be “too many planets.”

    • sysfailure0x5a

      Well, man, it’s just your opinion that he can’t state his opinion.

      • Angela Zalucha

        He can state his opinion that the IAU will re-vote. But he needs to make it more clear that it is an opinion

        • John Rooksby

          He needs to make it more clear *for you* but it was perfectly clear to many of us.

          • Angela Zalucha

            And that is where the disservice has been done.

          • John Rooksby

            I see. So your position is, ‘I’m not wrong’ because *you* feel the writer wasn’t clear enough *for you* (and an unknown (and unknowable) number of others) – even though it’s ridiculous for you to expect him to know how clear he needs to be for your benefit (and that of all potential readers)? Being a scientist you don’t need me to tell you that he was clear enough for some people and that you mustn’t discount this in any attempt to prove that he did a disservice.

            Could it not be the case that those who understood him outnumber, and so outweigh, those who did not; and that this would negate the existence of a disservice? I would say so.

            Now this would be a philosophical question which, I would suggest a) isn’t your field of expertise, and b) is unimportant to answer – much like the question of what we call Pluto.

    • John Rooksby

      The article then explains *why* this could happen and why,
      if it does, it will be in 2015 i.e. because a new probe is studying it this year and it may (and it’s reasonable to say this) supply sufficient new information that would make reclassifying it necessary once again. It was reclassified the first time after we learned more about it and learning *still* more will, naturally, either reinforce the current classification, support the *original*
      classification, or do nothing to suggest that any change is
      called for either way. Those, like yourself, who see this
      issue as the true scientist should i.e. objectively, without
      applying irrelevant value judgements to whichever designation Pluto’s gets, will not object to it being reclassified if the scientific findings merit it, would you? Thus, if what we learn does call for a re-vote then it will indeed happen. NB. The writer certainly *has* placed a value judgement on Pluto’s designation but he’s writing for a magazine and is, I
      would suggest, wearing his journalist’s hat and trying to bring a little colour to his report of the New Horizons mission.

    • laurele

      I respectfully disagree with the claim that those who believe Pluto needed to be re-classified because of the discovery of similar objects near its orbit “won.” They did not win anything. What they did was violate the IAU’s bylaws by putting a resolution on the General Assembly floor without first vetting it by the appropriate committee, as those bylaws required. The chair of the IAU’s own Planet Definition Committee, Owen Gingerich, said had he known this would be done on the last day of the conference, he would have canceled his plans to leave early.

      There are several other problems here. Many of those who voted against Pluto were and are motivated by emotion, specifically, a misguided notion that our solar system cannot have too many planets. That argument has no scientific basis whatsoever. Our solar system has whatever number of planets it has, and memorizing a list of names is not important for learning. It is an archaic throwback to the days when little else was known about the planets other than their names.

      It also makes no sense to say dwarf planets are not planets at all. Dr. Alan Stern, Principal Investigator of New Horizons, is the person who coined the term “dwarf planet,” but he intended for it to refer to a third class of planets in addition to terrestrials and jovians, not to refer to non-planets. What really needs to be amended is this specific IAU claim, that dwarf planets are not planets at all.

      What also needs to be amended is the requirement that an object clear its orbit to be a planet and that it revolve around the Sun rather than a star. This means no exoplanet can count as a planet to the IAU. Since we’ve discovered rogue exoplanets that do not orbit any star, requirements to orbit a star and clear its orbit must go out the window.

      The real mistake was made by the media, which gave the IAU a privileged position it never deserved. The IAU vote should not have been taken as gospel truth but as one view in an ongoing debate. Textbooks should not have been changed except to reflect that the debate remains ongoing. Reporting only the IAU view as truth has been a tremendous disservice to science.

      People from a wide range of backgrounds, from members of the public to amateur astronomers, to professional astronomers and planetary scientists care about this issue a great deal. This does not mean we aren’t interested in the science; on the contrary, it is that very scientific interest that compels us to question a decision that makes little sense and does not accurately describe the world that so fascinates us. The debate about whether it is a planet or not a planet has stimulated a lot of genuine interest in this little world and in the New Horizons mission.

      We do not need any IAU vote to reclassify Pluto as a planet. And those who support Pluto’s planet status are NOT “a small group of very passionate people.” They are quite a large group of planetary scientists who rightfully dislike the IAU definition as well as its arrogance in attempting to impose a definition on the world and repeated refusal to reopen the issue even when asked to do so by other professional scientists again and again.

      • Angela Zalucha

        My comment was that there are no plans to re-vote and that this author is misrepresenting that.

        I also expressed an opinion that I do not care to argue about this topic any longer.

        That is all.

        • laurele

          But instead of being annoyed by the topic, why not use it as jumping off point to educate people about Pluto’s characteristics, especially once we start getting those better than Hubble images from New Horizons? No matter what the findings will be, they will encourage people to think and question, to consider the issue for themselves. That is not a bad thing.

          • Angela Zalucha

            It is a bad thing when we want to teach people about Pluto’s physical and chemical properties. You brush off “No matter what the findings will be…” when that is the most important part of the mission. IT IS NOT to beat a dead horse about Pluto’s planet status.

    • Adrian Marshall

      Sadly, below this has devolved to a bunch of arguing; although, I must say that I really like what SGT K has to say, he makes very good and pretty well-worded points. But I have a question for the astronomers on here, so Dr. Zalucha: IF Pluto is reinstated and Ceres is named a planet, doesn’t that mean that there will be a lot of added planets? If there are other Kuiper Belt objects bigger than Pluto, they would all have to be added right? So there could be 100s of planets or so. I remember reading once that this too is why Pluto was “demoted” because there were other objects out there that would have to be added. Is this still true or not? Thanks

      • Angela Zalucha

        The logical answer is: Yes. Whether the International Astronomical Union would follow this pattern I can’t speak for

    • rsams777

      If you “hate repeating” a boring, dry answer to a question that is obviously important to many people (or they would not ask you) then remove the stupid “must clear the (undefined) area” specification and return Pluto to planetary status. Then you can prattle on about anything you would “rather be telling” us.

      • Angela Zalucha

        Yes, I am the IAU get on that right away.

        I don’t want to lecture you about anything. But if you’re going to start chatting me up on an airplane or some social setting I don’t want to sit there and take the blame as to why Pluto isn’t a planet.

    • Keldon McFarland

      Wouldn’t most astronomers and plantatary scientists rather study what makes Pluto and the other relatively newly discovered similar to Pluto unique? Isn’t it more fascinating to study this new type of solar system object?

      • Angela Zalucha


    • David Shafer

      If you don’t “hate” anything then simply reclassify it as a planet and make us happy. Otherwise your a “Pluto-hater.” If Pluto and Ceres have to “clear their neighborhoods” as part of the test of being a planet then Earth wasn’t a planet until after it smacked into Theia. Look, I want to know everything possible about Pluto, I’ve always liked it because I thought of it as the farthest outpost man will some day have; but when you label Pluto a dwarf-planet it’s something I can’t get past. Perhaps when you can better define the definition of a dwarf-planet it won’t be so difficult to accept. I’m not trying to be a jerk but your going to have to work through this with us. By us I mean those who wish to re-designate Pluto as a planet.

      • Angela Zalucha

        Fine. I don’t particularly care because I’m an atmospheric scientist and this “clearing the neighborhood” requirement has almost absolutely nothing to do with what I research. Most people want Pluto to be a planet again just because it was when they were kids. You at least have an understanding of the argument. However I do like to stick to the official events that have taken place, as a scientist. I hope you can appreciate it. If the IAU votes Pluto a planet again I’ll roll my eyes and keep chugging along. I slipped up last week and called Pluto a planet in front of a large audience. That was irritating, because then they didn’t want to listen to anything else I had to say (because both sides got worked up). I would probably abstain from an IAU vote, because it was the orbital dynamicists that demanded reclassification, and as I said above, it has almost absolutely no bearing on what I do for a living. I think however were it put to a vote again, most scientists would abstain, or, the dwarf planet status would hold. The pro-Pluto planet camp is a minority. A loud minority, but really not indicative of the viewpoint of most planetary scientists.

        • Angela Zalucha

          now can i get the 10 minutes of my life back having to write this post, which I’m sick of.

    • Robert Schell

      i don’t think the average citizen cares about whether an astronomer finds their questions irritating. If you find the pedestrian questions of the unwashed masses so dry and boring, perhaps you should step back from the public eye, or at least not go out publicly, and put yourself in Q&A situations where the ignorant, but curious individuals and their questions do not disturb your happiness.

      • Angela Zalucha

        I don’t put myself in the public eye. But when people ask me what I do for a living, I have to intentionally be vague, and sometimes it doesn’t always work. Also, few people are genuinely curious, most are quick to shout out their opinion that “Pluto is planet because it was when I was a kid!!!!” If they really want to know the International Astronomical Union definition of a planet and have an intellectual discussion about it, then that is fine.

    • carol12598

      If you could use extra payment from 50-300 bucks a day for doing basic work over internet at your home for few h a day then try this…

    • TheEdgeofMind.

      What is the definition of a planet? That is the crux of the issue. Is it? or isn’t it a planet? What defines a planet? Astronomers clearly do not have an understanding of that. The simple fact we do not know all that much about these matters and no scientists would ever claim to have a complete understanding of the universe or the development of our solar system. Like an artist, scientist paint a picture of the best understanding of their findings. Nothing more. Nothing less. Is it the right answer? No. The fact is we will never know.

      There are bigger objects then Pluto beyond Pluto. Most of which if not all are on there way out. Our universe is scattered with rogue planets. Our solar system’s formation is just adding more piss to that pot. Angela should know better then anyone to base an opinion on size and ignore that fact those same objects bigger then Pluto are on there way out. I know their is a gas giant on it’s way out of our solar system now that was discovered a while ago. The size its self does not determine if it is a planet or not, But it’s orbital behavior. I am pretty sure you’re not “a leading Pluto scientist” You seem to miss the fact this is a public interested story aimed at drawing public attention. Your being very counter productive.

      My opinion on the subject is planets are just a label we give to objects like we do with the labels “cat” and “dog” To help humanity as a whole grasp the universe around them. Nothing more nothing less. I highly doubt anything other then humans care about what is or not a planet. I wish both sides would quit debating over this useless topic, but it helps draw in public interests which keep the space program a float.

      It has and always be a ploy aimed at grabbing public attention. Which in turn creates funding for future space exploration.

      If you cant wrap your head around that. Than I highly doubt you know anything about Pluto or even the how the solar system was formed.

      We find stars in our galaxy older then the known claim of the age of the universe and even older elliptical galaxies. People who claim to understand how the universe is formed truly know nothing about the topic. Because astronomers cant even get around “The horizon problem”

      Take care, Angela
      Please remember to not get over zealous on these topics, because they good for the space programs as a whole.

      • Angela Zalucha

        The Internationa Astronomical Union, the international body that decides the names and category of astrnomical objects has no plans to vote on Pluto’s status at their annual meeting this year.

        You seem to think a lot of things. However opinion is not fact.

        • TheEdgeofMind.

          “The Internationa Astronomical Union, the international body that decides the names and category of astrnomical objects has no plans to vote on Pluto’s status at their annual meeting this year.

          You seem to think a lot of things. However opinion is not fact.”

          Nothing came for “internationa” that is not even a word.

          Second. I was not rude to you so please tone down your attitude. There is nothing to merit it.

          There is nothing that defines a planet, but what some people behind closes doors deem it. Just like the Vatican. Honestly you don’t know what your talking about. I sense your trolling since you can not spell. Yet you claim to be a “leading Pluto scientist”
          Where is your research located?

          As for Pluto it is a lot bigger then we thought it was. It has it’s own moon system and orbits the sun. Like i said “planet” is a label aimed at helping humanity understand the universe. Do I care if it is a planet or not? No. Makes no difference. Pluto like earth is just space junk left over from an exploding star orbiting around a central mass Nothing more. Nothing less. That is a fact.

          Get over your self. You are all upset with that attitude of yours. I think you should take your meds. You being pig headed about this as the people who say Pluto is a planet. Your just like them. It’s pathetically ironic.

          The fact you cant see that shows how mentally unstable you are.

          Like I said before you shouldn’t get bent out of shape by public interests stories.

          Please take care of your self Angela.

          Seek help. You really seem out of place here.

          • Angela Zalucha

            You should reread your own post for spelling errors.

            I am published in Icarus, the Journal of Geophysical Reseach, and the Journal of Atmospheric Science.

          • TheEdgeofMind.

            Yet your here trolling a public interest story on a blog.
            That was created to draw in public interests so you can get your funding for your projects. It is the tax payer and the public who pays you. They have every right to express what they think on the matter. If you want a job in the public sector you need to deal with that. It is the public who is paying you to research all day for the subject you are best suited for.

            Anyone with common sense would treat this for what it is.
            You lacked any and all common sense by posting here the way you did. That is a fact.

            Why cant they find funding for space research? Why are there so many cuts to the space programs? Because the science community belittles the public. You cant just rudely belittle people who are funding your research.. If you don’t like people calling Pluto a planet ignore it. The end.

            The only thing worthwhile I see about this mission is the fact humanity gets to see what is the farthermost reaches on our solar system looks like.
            As for Pluto being a planet? There is no such thing as a planet. “planet” Is a made up concept by humans to categorize an object. The truth is… It is all space junk.

            If you are a scientist. You know humans can never exist in space. If it is not the radiation that will kill humans in space it is the fact our bodies are not suited for the high speeds or zero g’s for long periods of time. We are stuck here and we are never getting off this rock. Until we find out how the Earth’s magnetosphere works and we don’t even have a clue.
            The mission to mars is a death sentence. Humans as of this century will never land on mars or even last a month beyond earth magnetosphere. Yet we keep hearing about how we will go to mars in the next decade. Which will turn into the next decade then the next.. and so on. Why? Because it draws public interest in the space program which in turn funds your research. Same reason people debate if Pluto is a planet or not or if it will be a planet again. Which why this article exists in the first place. The fact you didn’t understand that before posting here shows how troubled you are.

            Take care Angela. :)

            Ps. “You should reread your own post for spelling errors.
            I am published in Icarus, the Journal of Geophysical Reseach, and the Journal of Atmospheric Science.” Nice spelling btw.)

            Link your publication I would love to read it.

          • GamerWho

            @TheEdgeOfMind do you need a salve… for that BURN!?!

            I’ll see myself out.

    • Michael Kosak

      It seems only one of the various sexes on our planet gets these emotional meanderings on things scientific. Just like the one who INSISTED that one of the mars rovers was female so it needed a girls name.
      As prrof of my sciency-ness I will conduct a survey of the responses -vs- flames to this comment grouped by all 51 Google genders.

    • Zulqarnain Hayder

      Nice. Very useful knowledge…

    • asdf

      Sure you are a scientist and nor a 12 year old massive idiot?
      Because this whole thing just screams “moron!”

  • DiscoFountain

    Who made that picture? the dwarf planet list is longer than that.

    • TrophySystem

      Yeah, what about Eris, which is roundabout where pluto is as a member of the Kuiper Belt, and is larger than pluto. Eris is the real 9th planet, Pluto is the comet.

      • sadoul1

        If this isn’t fuel for an awesome sci fi movie I don’t know what is!

      • laurele

        Pluto is not a comet. Both Pluto and Eris are small small planets as well as Kuiper Belt Objects. The first tells us what they are; the second tells us where they are.

  • sadoul1

    I hope it turns out to be a frozen Mass Relay.
    Would love to say “Hi” to the Turians and Asari. :)

    • Mike Richardson

      Charon’s gotta be the Mass Relay. Pluto’s orbit will re-stabilize after we free the relay. *sigh* If only things worked that way. I think I’ll go play me some Mass Effect in a bit.

  • Feanor22

    Who cares into which manmade category a bunch of self-important astronomers put it into? It doesn’t change reality at all. This whole topic is silly. On the other hand, what New Horizons actually observers and relays back to Earth will be interesting.

    • Angela Zalucha

      Just to be clear not all of us are self-important…..but otherwise your point is what I am trying to say. There are 1000 interesting things about Pluto, and the majority of astronomers are interested in those things. We don’t sit around at science conferences debating Pluto’s status. School children seem to think that this is what we do, but the reason for Pluto’s status change was fueled by pinpointed scientific arguments.

      • Feanor22

        Sorry about that! You are quite right, of course….the science is what’s important. Thanks for calling me on my insensitive remark. I majored in astrophysics at UCLA, so while not a professional astronomer I am trained and have worked in science & education. I really envy and appreciate what you “real” scientists do!

        • Angela Zalucha

          no worries

      • laurele

        Except sitting around debating Pluto’s status–without the presence of many planetary scientists–is exactly what astronomers did at the 2006 IAU General Assembly. That was the mistake. They should never have opened this can of worms, but now that they did, it is hypocritical (for them, not you) to object to others taking up the issue.

  • mph

    The world is flat and planets are made of cheese.

    • sadoul1

      Stand fast for the coming of the great handkerchief!!!

  • Old_ones

    For some reason other dwarf planets like Eris (the largest known Kuiper belt object) and Makemake have escaped mention in this article. One would think that if Pluto and Ceres were reclassified as planets these would also need to be reclassified.

    • Guido Meyer

      exactly … the 2nd sentence in this “article” is wrong already; Pluto is not even “the largest object in the Kuper Belt”

      • laurele

        Actually, Pluto is the largest known object in the Kuiper Belt, as it is marginally bigger than Eris. That doesn’t mean another object might not be discovered there that is larger than both.

    • Angela Zalucha

      A different version of this article is floating around where he does talk about Eris (not to defend this guy). Also we’re not 100% sure which one is bigger, but we’re splitting hairs here, thanks for bringing this point up too.

    • laurele

      Yes, they would be. What is the problem with that?

      • Old_ones

        The problem is that the article implied otherwise. I don’t have a strong opinion about “planets” and “dwarf planets”, but the classification system should be discussed honestly and without misleading omissions.

  • john doe

    *rolls up newspaper, walks up to editor, and WHACK* NO, BAD, BAD DISCOVER MAGAZINE, BAD. We make poor scientific assumptions based on ignorance on Reddit, not on news sites. If Pluto was a “planet” again, That would mean Ceres, Sedna, Haumea, Eris, Make Make and Orcus are all planets, too, and that means, every grade school child is going to hate you.

    • Angela Zalucha

      You can have 8 planets, or you can have 15+, but you can’t have 9. I’m sorry if that number offends you.

      • laurele

        No one is saying it has to be nine. It may very well be 90. Many people, including kids, actually find the notion of more planets in our solar system to be exciting rather than problematic.

    • laurele

      Yes, they are all planets. So what? Children do not need to memorize a list of names. That is an archaic method of teaching dating back to a time when we knew little about these worlds other than their names. We don’t ask kids to memorize the names of all the rivers or mountains on Earth, just to understand what a river and a mountain are. Similarly, kids should be taught the different subtypes of planets and their defining characteristics without having to memorize a list of names. The strong objection to having “too many planets” in our solar system is based on sentiment, not on science.

  • William Watson

    “Only” 60% voted to not keep the planet designation for Pluto.
    Fixed it for ya. Where is my fee?

    • Richard Manning

      60% of those who voted. 3% of the total membership. Arguably, this doesn’t constitute anything near a broad consensus unless the remainder of the membership officially abstained. It’s certainly nowhere near a quorum; I’d say this was more akin to a House or Senate committee approving a bill than the full Congress doing so.

      But that’s just me.

      • Sue Masten

        As a minion, basically an Astronomy enthusiast online Astronomy 101 not part of the club I find this discussion disheartening.

  • CynicalWhiteGuy

    The whole Pluto demotion seemed to me more like an attempt to keep a number of people (such as Mike Brown and his team) from getting their names in the books with more Kuiper belt/trans Neptune “planet” discoveries. Academia has some of the strongest biases I have seen. Remember this change came on the heels of the confirmed discovery discovery of Eris. Just the way I see it.

    • Angela Zalucha

      I don’t understand your first point. But yes, it came on the heels of the discovery of Eris. People went, wait, there are more of these? Mirrored the detection of Ceres and subsequent asteroids completely.

      • laurele

        The analysis with the detection of Ceres is wrong because Ceres turned out to be very different from subsequent asteroids discovered (with some exception for Vesta and Pallas, which are intermediate objects between asteroids and dwarf planets). 19th century astronomers did not have telescopes powerful enough to resolve Ceres into a disk, so they had no idea it was any different from subsequent asteroid discoveries. Today, we know Ceres is spherical and therefore a small planet. This means the demotion of Ceres was in error. The discovery of Eris just meant we have another small planet in the solar system. It did not mean Eris or Pluto are no more than tiny, shapeless rocks in the Kuiper Belt.

    • Gregory J. Toma

      Of course it came quickly after discovering more objects like it. That is why Pluto need to be demoted. It’s a practical decision. The significance of something, not necessarily value or importance, but it’s significance is by definition dependent on it’s rarity.

      A large gemstone or precious metal is significant because of how rare they are. But if someone discovered huge and plentiful deposits of them tomorrow that made them easier to come by, then their value and level of significance would drop. The more common something becomes, the less significance it has.

      Pluto was originally labeled a planet because it was believed to be as rare and unique as the other eight planets. The size of it wasn’t nearly as important as our belief that it sat alone out there in it’s own orbit around our sun like the rest of the planets do.

      Ceres shares it’s orbit with millions of other asteroids, which is why it never has and never will be considered a planet. And once we discovered Pluto was also just another common part of a melee of objects sharing an orbit, re-classifying it was a given. If there was no asteroid or Kuiper belt, and instead just Ceres and Pluto then both would almost certainly be considered planets.

      But as it currently stands, arguing that either deserve a title with the significance reserved for the uniqueness of planets, is like getting upset because a newly discovered population of an animal species causes that animal to no longer be classified as endangered.

      • MysticPizza

        My friends it is a question of taxonomy more than anything else. When does the cambrian period started? and when did it finish? Was it 540 million years ago and 485 million years ago? Or prehaps it started 7 million years later and ended 20 million years before. Is a platypus a true mammal or perhaps it is just a glorified duck?

        We certainly should not be arguing about this. Why did the registered members of the IAU fled the conference on the last day of the convention? Couldn’t they have stayed if they really cared about the vote in Prague in 2006.

        To me it is clear that there are many reasons for Pluto to be studied and investigated instead of focusing on it’s aledged “demotion”.
        Pluto in only one of the 6 solid bodies in the Solar Syatem that has an atmosphere (the other being Venus, Titan, Earth, Mars and Triton).
        It has 5 moons, (probably there is a sixth lurking somewhere) it might have rings it’s obliquity close to 90º -only Uranus has a similar extreme obiliquity- and has many other interesting features we should be focusing on.
        For Instance Does it have a metallic Core, A magnetic Field? Why does the atmosphere not collapse when its distance to the Sun increases in it’s orbit. How much is rock and how much Is ice?
        Those are the Answers we might get from New Horizons. Whether it is a Planet or not won’t be the answer I can assure you.

        • laurele

          Those who left the conference early didn’t do so because they don’t care about this issue. They did so because they assumed that the discussion was over after the General Assembly rejected the recommendation of the IAU’s own Planet Definition Committee. They had no idea that those left would violate the IAU bylaws and throw together a hastily crafted resolution on the last day of the conference when most of the original 2,500 attendees had already left. One could say those who left were essentially deceived.

      • laurele

        Pluto never needed to be demoted. By your logic, terms like “star” and “galaxy” should have no value or significance because we now know there are billions of them. Yet do you hear anyone arguing that we cannot have too many stars or galaxies? Does anyone claim Jupiter cannot have 67 moons because the term “moon” is devalued if there are more than four?

        Your argument is economics, not science. Ceres is no more one of millions of asteroids than Pluto is one of millions of Kuiper Belt Objects. There are factors more important to the classification of objects than whether they share an orbit–factors such as the objects’ intrinsic properties, their compositions processes, etc. By privileging only location, you ignore these other important aspects.

        Ceres and Pluto are already considered planets by many planetary scientists, so saying they never will be considered such is already incorrect.

        • Gregory J. Toma

          “Your argument is economics, not science. Ceres is no more one of millions of asteroids than Pluto is one of millions of Kuiper Belt Objects”

          Exactly. Both Ceres and Pluto are insignificant due to the belts they belong to. And “star” and “galaxy” are of no significant value either. Unless you are talking about our sun, or the Milky Way, then what significant value could they possibly have? Are you saying that a non specific term like star that encompasses trillions is supposed to be just as significant as planets in our own solar system of which there are only eight?

          And are you serious trying to say that the 50 rocks smaller than 6 miles across that orbit Jupiter are of the same significance as the 4 actual “moons” known by name as Io, Europa, Ganymede, and Callisto?

          Come on, get real. You can be butt hurt all you want about Pluto, but don’t try to argue the definition of significance.

    • MysticPizza

      so your point is well taken. I would only ask why then didn’t the come in droves to the next conference and came in droves to right this wrong. To my uneducated point of view there two and only two reasons why Pluto was considered a planet. The main one is becuase when discovered it was thought to be massive enough. No one ever thought it would be less massive less wide that Mars. As a matter of fact it was thought to have a mass comparable to Earth. The second reason , and the LESS inportant one was that it was discovered by an American and the US being such an important country in the scientific community of the 20th century had not discoverd any of the 8 palnets and none of the first 4 asteroids Ceres, Pallas Juno, Vesta, . So it just felt right.

      Fast forward a few decades, had it been discovered on the 80 after Chiron and a satellite like Charon would have stablished it’s true size then i would have been almost surely catalogued as an Asteriod.

      By the way I am not anti-Pluto. Nowadays probably Eris and a few new Kuiper worlds are potantially candidates for planethood. You just needs to show in numbers and convince us why is it worth to be considered as a PLANET.

      In the meantime, focus on the positives and be elated that New Horizons is opening a new world for all us.

      Live long and prosper!

  • Ralph Brandt

    I guess i am the only one asking this. Why would such a change be made on a vote that had a dwarf segment of the voting body? Come on. Did someone figure this to skew the vote? With today’s communication couldn’t the vote have been more than 3% of the members or maybe you are gazing a the stars so much that you are not aware of phones, video conferencing and the internet? i am not an astronomer, i am a statistician and a network engineer. I haven’t set down and calculated the probability that this was a valid vote but I would be far more convinced of its validity if 30% had voted.

    • Angela Zalucha

      it’s true, it was far from a quorum. I don’t know why some peole vote, but I’ll toss out this: the International Astronomical Union comprises astronomers from birth of stars, death of stars, origins and fate of the universe, galaxies, extragalactic structure, the interstellar medum, exoplanets, and the Solar System. Now, of the Solar system scientists there are heliophysists, geophysisits, geologists, atmospheric scientists, orbital dynamicists, magetosphere people, icy satellites, and sorry if i missed your discipline. So, out of all of those groups, most do not keep up with the Kuiper Belt science and were not even really qualified to vote on the subject, and thier non-voting could be considered abstaining. I would suggest to be qualified you must have published a refereed article related to KBO science (similar to the statistics for scientists who believe in man-made climate change)

      • laurele

        But most who voted were not planetary scientists either, meaning they were not really qualified to vote on this matter. The appropriate specialty isn’t Kuiper Belt science; it’s planetary science. That includes exoplanets.

        Planetary science has come into its own as a field in the last 50 years. Why not have an organization of planetary scientists vote on this issue?

        Additionally, no absentee or electronic voting was allowed for this vote. This means non-voting wasn’t abstaining; it was largely due to the logistics of people not being in a particular room on a particular day to vote on a resolution no one knew was coming. The IAU violated its own bylaws by putting a hastily crafted resolution thrown together on the last day of the conference to the floor of the General Assembly instead of first sending it to the organization’s Planet Definition Committee as required. The chair of that committee, Dr. Owen Gingerich, has stated publicly that had he known this would happen, he would have canceled his plans to leave the conference early.

  • Donny Vang

    There’s no doubt Ceres and Pluto are planets. They not only revolve around the sun, but they also have their own alibis too…moons moons moons! If Pluto and Ceres don’t qualified for the last and final berth…last dance, well when March madness comes around, only sweet 16 or so gets to go and you can scratch the rest of 64 teams! For pro football and baseball, no wild cards team in playoffs! I’m rooting for Pluto and Ceres…underdogs on top!!!

    • sadoul1

      GO HAWKS!!!

    • 7eggert

      Many asteroids have moons, too. I pity the kids of tomorrow if they have to learn each tiny-asteroid-with-moon’s name.

    • Angela Zalucha

      you can have 8 planets, or 15 and counting. can you name all 15?

      • laurele

        It’s not really important to name all of them, just to understand the different subclasses of planets and their characteristics.

  • Alex Beemer

    “hear about Pluto? Messed up right?”

  • Aaron Eiben

    Alright, supposing the word “dwarf” is removed from classifications of Pluto and Ceres (though I am not sure how that improves anything), what happens to Haumea, Makemake, and Eris, which are also currently classified as dwarf planets by the IAU? Do they become* planets, too? (*Emphasizing that the IAU’s classification of a solar system object has absolutely no effect upon it.)

    • laurele

      Dwarf planets should already be considered a subclass of planets. That was the intention of Dr. Alan Stern when he first coined the term.

  • Dr.Gary james Baxter

    I would like to see them re-classified as a planet again. We don’t know what the rest of the universe is , we only speculate. Who is to say the conditions that both Pluto and Ceres are in is not normal . As research and exploration get better and more probes sent out to explore the universe we will have to change how we classify things .

    • Angela Zalucha

      that is true. science is always revising itself. so you may be right.

  • Evan

    Something I have noticed is a lot of people are focusing on this being a science issue, when it is not. This is a classification issue. When classifying objects the goal is to get at the core of what an object is. Right now the current definition of a planet is a piss poor definition for classification. The definition doesn’t just look at the physical attributes of the objects, it also looks at the behavior of the objects.

    The problem with this is the behavior is 100% circumstantial. Whether or not an object is revolving around a star is circumstantial to if it is near enough to a star to revolve around it. The clearing of its orbit is circumstantial to many factors such as location, time, and orbits of other objects. Both of these are used to define what a planet is, but neither of them define what these objects are physically.

    Take for example the categorization of animals. They do not categorize lions and tigers as completely different kinds of animals. Instead they recognize there is some basic commonality between both species that separate them from wolves. So we define them both as cats, and each species is just a sub-categorization of cats.

    Celestial objects should be no different. In order to define a planet we should be looking at what is common between these objects that separate them from other objects (mainly asteroids and comets). The difference is the amount of gravity forces these objects to be nearly spherical, while asteroids are non-spherical. This means the base definition of a planet a spherical object that does not maintain nuclear fusion.

    Remembering back to when Pluto was demoted from reading the articles and such, it seemed to me the main push to demote Pluto was not scientific or categorical in nature. Instead it was an emotional response to seeing the idea of a planet becoming less special as there was an influx of new spherical objects being found in the Kuiper Belt. As someone who values logic and understanding in scientific community it is embarrassing how illogical and uneducated the astronomical community was in approaching this matter.

    • sadoul1

      Passion has its place, even in Science. I’d rather the unruly mob was up in arms about ANYTHING scientific, at least that means they aren’t shuffling about their lives, lacking wonder at the marvels out there. What good is our bringing science to them if they don’t give a fig?

      • Evan

        Having a passion for science is not the same as allowing passion to affect your scientific (or in this case categorical) beliefs. Science and categorization is about logic and facts, not passion. When you allow passion and emotions to affect how you view things you are not doing scientific work as the basis for the conclusions is no longer fact based.

    • DrPlokta

      Actually, the definition of a species *is* also situational depending on behaviour. Two populations that interbreed are a single species. The same two populations with a reproductive barrier of some kind preventing them from interbreeding would be two different species.

      • Evan

        First of I was talking about cats which is the family felidae. A species is two levels below that.

        Secondly no, their behavior does not make them separate species. One tigers and lions can interbreed, yet are considered different species. What makes them the same species is DNA, not behavior.

  • Iceman

    I don’t give a cr@p! Be it nostalgia or whatever, I want Pluto back!

    • sadoul1

      Pluto is still there, only now, instead of being the straggler of a string of planets, it is the largest and king over an entire host of comets. Pluto wasn’t demoted, Pluto got promoted!

      • DrPlokta

        Probably not the largest. Eris is probably larger.

      • laurele

        Pluto is not a comet. Comets are not large enough to be rounded by their own gravity. They are not geologically differentiated into core, mantle, and crust. They do not have geology and weather. None is anywhere near Pluto’s size.

        Comets lose mass each time they come closest to the Sun, eventually breaking up entirely. This does not happen to Pluto. In fact, a recent study suggests Pluto may never completely lose its atmosphere during its 248-year orbit around the Sun.

        Eris is not bigger than Pluto. It was initially thought to be so but a team of astronomers obtained a more accurate measurement of it in Nov. 2010 and found it to be marginally smaller than Pluto. According to the geophysical planet definition, it does not even matter which is bigger; both are well beyond the threshold for being rounded by their own gravity, and both are therefore small planets.

  • Aaron

    Terrible article. There is a clear and known definition of a planet’s “neighborhood” and exactly what it means to “clean out” that area.

    A planet’s neighborhood is anything along it’s orbital path that falls within the planet’s relative gravitational influence.

    And cleaning that area entails that the overwhelming majority of objects are either pulled down onto the planet and added to its own mass, captured in an orbit around the planet, or flung off into the void, within the geological timescale.

    Neither Ceres nor Pluto do these things. The only difference between Ceres and the asteroids is its size and shape, and perhaps its composition. That’s it. The same is true of Pluto, and any number of other objects in either belt region. If we make Ceres and Pluto planets just because they’re big and round, we’d have to make dozens or more of other similar bodies in the Kuiper belt alone, into planets.

    We have an 8 planet system with probably dozens, if not hundreds, of dwarf planets, and thousands or more of similarly large comets and asteroids.. Deal with it.

    You…are a sensationalist, with zero concept of what you’re writing about, just trying to drum up views. This is “journalism” at its worst.

    • DrPlokta

      Smaller objects can also be in an orbital resonance with a planet that has cleared its orbit. As in fact Pluto is with Neptune, which otherwise wouldn’t have cleared its orbit, since Pluto crosses it. Yet another reason why Pluto shouldn’t be classified as a planet, since it’s a bit odd to have a planet that’s gravitationally tied to another planet.

      • YeahRight

        Not one planet has cleared its orbit, there is always debris in stable libration points. In case of Neptune it’s even worse… it happily coexists with Pluto, which it hasn’t cleared, either. That part of the “definition” simply misses pretty much everything a first year astronomy student is required to know about orbital mechanics.

        • DrPlokta

          The definition of clearing an orbit allows for smaller bodies to be in orbital resonance. So the libration points (1:1 resonance) and Pluto (3:2 resonance with Neptune) are not counted for the purposes of working out if an orbit has been cleared, any more than moons (also in a 1:1 resonance) are.

          • YeahRight

            Do you notice how you have to make up ever more rules to make Neptune a planet and to exclude Pluto? Here is a much simpler rule to go by than all this non-scientific nonsense that the IAU came up with: “Mercury to Neptune are planets.”. See how easy that was?

          • DrPlokta

            Your “simpler” rule doesn’t work, because it’s very possible that there are one or two genuine planets in the Kuiper Belt or beyond, and you don’t allow for that possibility. Whereas the rule “There must be nothing else near a planet’s orbit that’s not gravitationally bound to it” is both simple and sensible.

          • YeahRight

            What a planet is is a matter of definition. My definition is simple, yours is complicated, they both achieve exactly the same stupid objective. If there are other near spherical objects in the Kuiper belt or beyond, they have definitely not cleared their orbits, nor will they ever, so no, no more planets beyond Pluto by the IAUs idiotic definition.

    • laurele

      Size, shape, and composition are major aspects when it comes to defining things! Do any asteroids have subsurface oceans or geological layering or weather? Ceres and Pluto are far more like the terrestrial planets than they are like asteroids. Blurring the distinction between two very different types of objects is hardly good science.

      Comets are largely iceballs, and the biggest known comets are nowhere near the size of Ceres, much less Pluto. Asteroids are essentially rocky rubble piles–very different from objects in hydrostatic equilibrium, which are shaped by their own gravity as opposed to by chemical bonds. As New Horizons Principal Investigator Dr. Alan Stern, who has studied Pluto for 25+ years says, “And I can’t think of a single distinguishing characteristic that would set apart Pluto and other things that you’d call a planet, other than its size. So I like to say, a Chihuahua is still a dog.”

      We do NOT have an eight planet system. We have a 13 and counting planet system. Yes, our solar system may have hundreds of planets. Deal with it. Artificially limiting the number of solar system planets for convenience is not science.

  • Martin wong

    I am very happy with Angela Z clearing the air on this topic. Personally I am also running out of patience with this discussion here and elsewhere getting nowhere. There should be a closure to this subject as the renaming of Pluto status has been done democratically the last time. The most qualified scientists had decided and things have to move on. There are so many important questions about astronomy that required time and human resources to answer. To be bogged down with this for a long time is not very good use of our mental capacity for a scientist

    • laurele

      It was not done democratically at all, and those who voted were NOT the most qualified experts in the field. Most were not planetary scientists but other types of astronomers.

      Four percent of the IAU voted on this resolution, and their decision was formally opposed in a petition by an equal number of professional planetary scientists. The IAU leadership has been repeatedly asked by planetary scientists to reopen this issue and has blatantly refused.

      Why a sudden need for “closure” other than to have your view cemented as “reality?” New discoveries always call for reconsideration of issues previously thought to be settled. Every day, weirder and stranger exoplanets are being found that do not fit any of our theories about how planets form and where they are “supposed” to be. Our concept of planet will and should evolve with each new discovery, not remain stuck in one dogmatic view people are expected to accept for all time.

  • Bob

    Maybe “planet” in the Pluto vs. Mercury sense is a popular culture concept referring to the 9 bodies we learned to name in elementary school, and not a proper scientific term. Scientists can probably just talk about particularly bodies and their properties without getting involved in this dispute at all.

    • YeahRight

      You are right about one thing: the IAU messed up big time and has subverted the presentation of scientific thought to the public.

  • Real Black Sheep

    All this speculation. Where are the facts?

  • DrPlokta

    Well, if you moved the Earth to the middle of the sun, it wouldn’t be spheroidal (for very long) or orbit a star, so I guess you also think that whether or not something is a planet should be location-dependent.

    But the real question is, how many planets do you want there to be? If a planet is something spheroidal orbiting a star, then you also have to add most or all of Eris, Makemake, 2007 OR10, Haumea, Quaoar, Sedna, Orcus, 2002 MS4, Salacia and Varuna. And probably dozens more yet to be discovered. Are you happy with the idea that there are several dozen planets orbiting the Sun?

    • YeahRight

      What’s wrong with having several dozen or even hundreds? Where do we get the rule from that there can’t be more than ten or a baker’s dozen of planets in any one system? In any way, according to the IAU definition there are exactly eight planets in the entire universe and that sounds like someone had a bit too much anthropocentrism for breakfast.

  • Erin O’Quinn Author

    Well written. Compelling evidence that we need to welcome back our friends into the interplanetary par-tay.

  • John J

    Actually they should state the facts that there are only 2 planets in our system. Mars and Earth. These are the only one that can support life. All the other planets are just hot rocks and gas which no human can live on.

    If we find Pluto has an atmosphere and it turns out to be O2 or CO2 there is a chance we could colonize it, thus, it would be a planet. But just basing it on size is like saying a size 2 shoe is not a shoe and only a size 10 shoe and above are considered to be a shoe because their bigger is scientifically wrong.

    • YeahRight

      Are you in the business of making up worse definitions than the IAU?

      • John J

        You took what I said the wrong way. The ridiculous point I was making is to show how ridiculous the status designation change was if the change was only based on object size – If that is, in fact, why they now call Pluto a dwarf planet.

        • YeahRight

          Ooops… my sarcasm detector was broken, but I can see that it’s kind of hard to beat the IAU at their game, even in jest.

    • laurele

      Ceres may be capable of hosting microbial life if it has a subsurface ocean. Other locations in the solar system that could host microbial life are Jupiter’s moon Europa, Saturn’s moons Titan and Enceladus, Neptune’s moon Triton, and yes, Pluto and Charon if the latter two have subsurface oceans.

  • Veronica Hamel

    “But in a few months, a few intrepid humans will pull back the curtain on Pluto”. What is this supposed to mean? That people are on the spacecraft. A really dumb way to say that those administering to the spacecraft from Earth, since it is mostly automatic, will communicate with it after it does its thing.

  • Rick Vickers

    Interesting article,

  • Timothy Rollin Pickerill

    Charon is not a moon, Ceres is not an Asteroid.. and no there are not “Pluto -haters”

  • Valentino Pintus

    whoever wrote this article needs to go talk to Neil deGrasse Tyson and have him explain why Pluto isn’t a planet anymore.

    • YeahRight

      Don’t make good old Neil talk even more nonsense than he usually does.

  • YeahRight

    Yes, I think we agree that the IAU leadership is full of themselves.

  • Dr.Gary james Baxter

    The biggest issue I see , Things and view points are always changing. We are still exploring. This could be the norm, then again it might not be . There are still too many unanswered questions out there . We need to send more probes and build better techs , in order to see what will stand and what will change.

  • matthew

    great article

  • Maurizio Morabito

    Let’s see. Not being a planet, Ceres has been neglected until Dawn. Most people weren’t told of its existence at school. Not being a planet any longer, Pluto has been disappeared from textbooks. Most people are not been told of its existence at school. Please somebody explain how this has been advancing science . I can always use a laugh.

    • YeahRight

      Whether you knew about Ceres or not depends on your school, but it’s true that the public outreach of many institutions used to offer a rather incomplete picture of just how complicated the solar system really is. Textbooks that are striking Pluto instead of adding Ceres and other smaller bodies in the outer solar system belong into the dumpster.

  • Steve Colyer

    Great article and I am sorry to see so many holding to the IAU’s terribly biased vote on the last day at Prague in 2006. First, Astronomers have no business defining: Planet. That is for Planetary Scientists to decide, and most of those voting that day were not Planetary Scientists. In fact most Planetary Scientists have an “I’ll know one when I see one” attitude on spherical worlds. The IAU had no business defining “planet” in the first place, and no object should be defined based on where it is (Astronomy) but rather WHAT it is (Planetary Science, in this case).

  • Yael Dragwyla

    “Official” re-vote or not, in the court of public interest and in that of real scientific reasoning, Pluto and, perhaps, Ceres continue to fascinate the public and many scientists in their own right, and the International Astronomical Union may well become superfluous and irrelevant thanks to the public backlash they have been courting with their aggressive, spiteful, and downright disrespectful attitude toward the public as well as solid astronomical science itself. Saying “Pluto is not a planet because it’s a *dwarf planet* is utter doulbethink and doublespeak, intended to confuse and cow the public and those scientists who do not agree with the IAU and its secret vote on Pluto’s “status.” So far they’re having precisely opposite effect from that intended on the general public and scientists who see right through the bulls**t being slung around by the IAU and their allies, su,ch as Mike Brown of the California Institute of Technology.

    Furthermore, simply slapping a new label on something is *not* science. Re-labeling a phenomenon requires proof of the new label’s appropriateness, and so far, that has not been forthcoming when it comes to Pluto. Illogical — “Pluto is not a planet, it’s a *dwarf* planet!” — and confused, the rationalizations for the re-labeling of Pluto are an insult to the public’s and reasonable scientists’ intelligence. An 8-year old child could see right through that, becoming utterly disusted by this attempt to pull the wool over the public’s and science’s eyes, causing him or her to lose trust in his/her elders and teachers because of what are obvious and inept prevarications and manipulations.

    It’s time to go back to 2005 and once again recognize Pluto and Ceres as the planets they are. And the hell with the mainstream media — they are NOT scientists, not well-trained in science. Their motto is “If it bleeds,, it leads,” and, sensing a strong potential for a great deal of hoo and large quantities of hah in this false controversy, they’ve latched on to the “side” they think will cause the most havoc, hence the most “blood,” without giving a damn about the serious and well-founded rebuttals of the IAU’s position that have been ongoing since 2006.

    This ain’t football, folks. It’s a serious scientific discussion with way too many politicized scientists and others who don’t give a damn about the science, only about “winning,” when there is nothing to win by their stance.

  • laurele

    The point here is, there should be plans by the IAU to revisit the issue of planet definition based on the findings at Ceres and Pluto, plus Dawn’s findings at Vesta, and increasing exoplanet discoveries. Noting all these, I wrote to the IAU Secretary General in late 2012 asking that the IAU reopen the discussion at its 2015 General Assembly. More than two-and-a-half years in advance, he expressed confidence that no IAU member would want to do this. If that is true, it’s because scientists who reject the IAU definition have already repeatedly asked for the discussion to be reopened and have had their requests refused. At this point, they are just ignoring the IAU altogether. It seems like the IAU leadership has made up their minds in advance, and nothing can motivate them to reopen the discussion.

    Maybe it’s time to think about another option–the formation of a new organization specifically devoted to planetary science. After all, who better to define the term planet than those who study planets full time?

    • YeahRight

      Yep, that’s pretty much it. The IAU is digging in and nothing will change until the people at the top have been replaced. Having said that, I am a physicist, and to me the nonsense of the IAU is completely irrelevant, anyway.

  • EarthlingX

    1. If it’s big, round and shines, it’s a star;
    2. if it doesn’t shine, it’s a planet;
    3.if it’s not round, it’s an asteroid.

    Complications arise due to the changed view we have of things. We don’t see those objects only through telescopes anymore, they are not wanderers and stars, but real things, we see them through the eyes of probes sent there.

    I’m not that fixed about the above definitions, but those i can understand and when somebody talks or writes about them, i know what it’s about, as in “Jupiter is a dominant, gaseous planet with many satellite planets and named satellite asteroids; the Moon is a satellite planet”.
    Blame Galileo for that, but he’s already been burned. We had no idea the Earth was a planet before that, but now we do and we know what planet looks like, something like Mars or Venus, big and round, like Jupiter or small, like Ceres.

    Sun is a star, so that’s what stars look like, they shine a lot. They tell me that brown dwarves don’t, but white dwarves do, similar to neutron stars. Black holes are a monster i’d rather not talk about, they probably deserve a special class.

    Our view has changed.

    • YeahRight

      You have a very good point, the difference between planet and star is much, much harder than the difference between planet and dwarf planet. The latter, of course matters next to nothing, while the former matters a lot. That didn’t stop the IAU from making fools of themselves, of course.

  • EquusMtn

    Do the semantics really matter that much? Whether we call Ceres and/or Pluto planets isn’t going to change them one iota.

    • Maurizio Morabito

      if it did not matter, textbooks would not be rewritten. Actually, if it did not matter, nobody would have de-planeted Pluto.

      • EquusMtn

        Maurizio and YeahRight: This is exactly my point. The semantics matter only because of the importance we as humans attach to them. It’s the tail wagging the dog — what should be a minor issue (because it has no impact on our understanding of the real nature of these objects) is causing us to expend a ridiculous amount of energy and resources in its resolution.

    • YeahRight

      It mattered enough to the bureaucrats of the IAU to make a mockery of rational scientific definitions.

  • Matt (82)

    yessss!! Don’t listen to the haters, pluto! you ARE who you were Meant To Be!

  • James38

    Nice article, well crafted sentiments. I was always comfortable with Pluto being a planet, and I agree “Pluto is, was, and has always been a planet, albeit a small one.”

  • Elizabeth Smith

    I’m sure the planet or planetoid Pluto has great concern as to whether or what a group of subatomic particles in the solar system decide it should be called

  • Debbie cantor

    The tyrant chorus is mortifying
    “This doesn’t belong in discover”
    So become an editor
    This is how scientific consensus thwarts progress, there shouldn’t even be a vote on global warming, that sent a chill up my spine.
    People this is a Popsci mag and in my non atmospheric science non philosopher opinion (the humble brags on this forum are astounding) it’s a charming article.
    The author took a position. Apparently that’s the offensive part.
    I would’ve thought this set of responses would’ve centered around the definition of a planet only not people pistol whipping each other and whipping out credentials to try to make others kowtow which apparently does work

  • jimoppenheimer

    I was greatly amused by the emotional rhetoric in this article. Nothing like the author giving away his obvious bias right out of the starting gate!
    Fact is, it takes little to see the difference between the categories, and Pluto does not really seem to belong to the class “planet.” In addition, taking it from the role of wimpiest planet in existence to one of the biggest comets is not that bad, and probably reflects the nature of this object.
    Time will tell, especially of writers can continue to act mature and abstain from wild, emotional dribble that helps no one. Ceres became a planet for obvious reasons, and was reclassified (“Pluto-ed” indeed !!!) for obvious reasons. The same process is going to continue to proceed with any new discoveries. It’s quite possible we may discover a really huge object out there, and may have to wrestle again (and again and again?) with our definitions.
    Science is not static. We learn new stuff, and this new stuff drives how we view stuff. To say, as this writer obviously does, that we should view Pluto as a planet because we’ve always done it that way is not scientific.

  • Wings_42

    To quote Shakespeare, “What’s in a name? That which we call a rose by any other name would smell as sweet.” (punctuation modified to conform to modern English). Whether Pluto and/or Ceres are called “planets” pales in comparison with their existance and the details of their composition, location, configuration and influence on their surrounding areas.

    I enjoyed the article, comments, and discussions. Thanks all.

  • Billie Mudry Spaight

    I think Pluto should be re-planeted. It should be “grandfathered” in because it circles our sun just like the other planets do. It’s not really an asteroid or somebody else’s moon. Besides why do we need to discriminate against dwarves?

  • Billie Mudry Spaight

    Just like a human dwarf is considered a person, a dwarf planet should be considered a planet. It’s only logical.

  • nik

    Whats in a name?
    ‘A rose by any name, will smell the same!’
    [deliberate misquote]

  • Llama Dood

    still have planet in their title, but didn’t mention Haumea, Makemake,
    or Eris…also dwarf planets. Jupiter, Saturn, Uranus, and Neptune are still Gas Giants. :p

  • Emkay

    Pluto is a big stupid dog at DisneyWorld… move on…

  • Toronto_Sky

    Only an irrational person would think Pluto needs to be a planet, what a terrible clickbait article. Indeed, the argument is literally emotional, and just getting mad at the IAU, fact is, the only problem with the IAU is the definition, most planetary scientist do not see a point in calling it a planet either. Classification may be subjective, but they also should be rational and efficient. Calling Pluto a planet would also mean calling thousands of other objects in the Solar System, and the Oort Cloud, man, there probably are a hundred more pluto sized objects there and it would be moronic to call them planets, you would literally have a solar system with 8 planets that are all very similar to each other, and over thousands of object orbiting the sun in completely different planes and orbits from the other 8. Why even stop there? Maybe call any major Asteroids and Comets planets too.Talk about a total devaluing of the word “planet”, because when people think “planet”, thousand of small icy rocks is not what they have in mind. Dwarf Planet is a good enough title for them, it makes it far more efficient.

  • Padraic J Shaw

    Pluto-haters? Really??! I think Pluto IS fascinating. I am THRILLED that NH will soon be whizzing on by (and saddened it is only a whizzing by) BUT I also think it should NOT be a planet. What about Eris? Are you discriminating against it, because of it’s location, much further away than Pluto? Or is it just because we will not know about it in detail in our lifetime, because we have no planned mission to Eris. Although smaller than Pluto, Ceres can clearly claim it is the ‘champion’ of it’s realm. Pluto cannot, has a bunch of mates near it’s size. The real debate will be, if we do find an earth or Neptune size object in the Kuiper belt or the Inner Oort cloud. Especially if it is the one that determine the orbits of Sedna and 2012VP113??

  • jimbow

    Correct me if i am wrong sense Pluto crosses Neptune’s orbit then Neptune did not clear Pluto out of it’s neighborhood so is Neptune a planet? LOL

  • Malicex

    “Some planetary astronomers would argue that were the Earth placed
    in the Kuiper Belt, it would not be able to clear its neighborhood and thus would not be considered, by the IAU definition, a planet; apparently location matters. Here a planet, there not a plane.”

    What about moons then? There are moon that are larger than planets. If you moved one of them to another location, they would be considered a planet.

    And what about Charon? I’ve heard Pluto-Charon being described as a two planet system, because they are so similar in size that they basically orbit each other. What if Pluto became smaller, would Charon then become a planet? Or should they both be considered planets?

    Meteors and meteorites are basically asteroids at a certain location.

    “In 2015 we will come to understand that dwarf planets are planets, too.”

    Well ya. They’re dwarf “planets”. Small lakes are lakes too. Ponds are bodies of water, like lakes, but smaller.

  • Foxhanger

    Ok, “leading Pluto scientist”: Lighten up. This is a “pop” culture Science magazine. They often (and sometimes humorously) use titles as “hooks” to get people to read their articles. This is not a scientific journal. For the purposes of this magazine they are getting people interested in Pluto again. I’m sure everyone will appreciate your additional information, but if you are going to nit-pick, this is the wrong place to do it.

  • Thomas

    PLUTO IS A PLANET!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  • Frank Wiley

    My very eager mother just served us nine… WHAT??? PIES, of course! Pluto will forever be enshrined as the ninth planet as long as that mnemonic exists, regardless of the efforts of a few eggheads to split hairs…

  • CesarSan

    237 of 10,000?

    237 of 10,000?

    What kind of organization changes something like that with only 2% of the members agreeing to it?

    The IAU is a bad joke.

  • Keldon McFarland

    Pluto should not be called a planet because it is so unlike all of the other planets. Rather it should be embraced as the first discovered object of its kind, a plutoid. There are many more trans-Neptunian objects being discovered.
    Why do so many people get emotionally attached to the planet/non-planet designation? It’s more fascinating that other and new space objects are being discovered and studied.

    • Stranger in the Alps

      Pluto is a lot more like Mars than Mars is like Jupiter.

      • Keldon McFarland

        And a round ball is round.

  • David Wright

    I find it a good thing when the discussion of science, in general, and planetary objects classifications, in particular, spark the imaginations of the average individual. It matters not, the eventual outcome of whether or not Pluto is re-elevated to planetary status again, Or that Ceres joins it. We all need to chill, and not take ourselves so seriously!

    Carl Sagan, in his lifetime, recognized that ordinary people need to be educated in the sciences. They elect politicians, who in turn, vote to fund a variety of scientific endeavors. Now, Neil deGrasse Tyson has taken up Mr. Sagan’s mantle to educate and inform the non-scientist populace. All in an effort to promote and make the sciences accessible to the average citizen. Controversy is a good thing. Mostly because it encourages discussion and debate. It doesn’t matter if we agree, only that we are talking.

    Galileo spent the last years of his life under house arrest for opposing
    Church orthodoxy that the Earth was the immovable center of the universe. There will always be religious or political entities with their own implacable set of beliefs. I personally think that politicians that refute evolution are a bunch of twits. But I respect their right to express their opinion. (Even if they are wrong!) The disturbing thing is when their opinions affect the educational curriculum of our school systems.

    If anyone is to call themselves a scientist, they should recognize a duty to educate the public, not to talk down to, or present an elitist attitude. That kind of arrogance does not serve the cause of science, it only diminishes it.

    No person lives a truly solitary existence. We all need to work to try to understand our fellow man, or at least respect other viewpoints. Even those that conflict with our own. Not just in regard to the sciences, but in religion, philosophy or any other societal pursuit. Because if we don’t, it won’t matter. There won’t be anyone around left to argue the insignificance of planetary classification. We will have long ago killed each other off for daring to have an opposing belief or opinion.

  • ISDAMan

    Perhaps, if everyone recalls the title of this article, “Pluto a Planet Again? It May Happen This Year”, and relates the content to it, it may be realized that there is some prognostication going on here.

  • Jim Weisgram

    Ok, this reply is intended to be humorous, no flames please…

    The book by Mike Brown

    How I Killed Pluto and Why It Had It Coming

    clearly shows the depth of feeling a scientist can have for an inanimate chunk of rock.

    Of course if you actually read the book you’ll find something quite different.

  • spongeblog


  • MIke Belyayev

    Simply put, Pluto should not be reinstated as a planet, and
    should remain a dwarf planet. The resolution vote at the IAU in 2006 clearly
    outlined the definition of what it meant to be a planet, and Pluto doe not
    satisfy the 3 criteria. It does not dominate its neighborhood. Furthermore, if
    Pluto is renamed a planet, then every celestial body that is discovered in
    orbit resembling Pluto must also be a planet. It would result in our solar
    system having 50 plus planets. It makes sense to have the separate distinction
    of dwarf planet for those that are similar to Pluto, and leave the planets that
    actually satisfy the criteria as planets.

  • ddfg

    pluto, the largest planet in the kuiper belt? Are you kidding? The whole reason they ruled pluto out as a planet in 2006 was because they found an ice ball bigger than pluto (Eris). The only reason they kept calling it a planet even after finding more and more ice balls was because they never found one bigger than pluto, until they did.

  • Brieone Harfoot

    Why does it even matter if the celestial object Pluto is titled as a planet or not? Would its tittle changing do anything aside from affecting someones feelings? I believe the definition of planets should only be made more accurate for purposes of analyzing newly discovered solar systems, for I imagine its more important to use the definition to better determine if a celestial body of a solar system orbits the sun and can clear its neighborhood of threats to evolving life. Also, I feel that that one would have to first figure out if the celestial body, orbits the sun, clears its neighborhood, etc, before even considering it to be a planet or not.

    As a Writing and Linguistics student, I do not see what the definition does for science other than helping the general population understand the difference between celestial bodies.

    And, I wouldn’t even touch the grammar argument on this page with a 10ft pole. But the Sarge was write. Shutting down conversations is ignorant, for it limits the transference of knowledge, where as the offended alumni could better explain what is misunderstood to dampen the misunderstanding by allowing some of the general population to gain an understanding. ; )

  • SCParegien

    I am a scientist and one thing holds true. Until we get a probe into Uranus we should consider Pluto at the very least a co-dependant cousin who comes around every few years or so and asks for money, then leaves in the night with your cigarettes.

  • Imran Latif

    I say to the author, if the Earth orbited Jupiter would it still be called a planet? I don’t think so, instead it would be called a moon of Jupiter. It seems location does matter a lot when you define a planet.

  • Charles Corso

    All lies, NASA has stolen $1 Trillion from the U.S. taxpayers since 1972. They are faking space, all your so-called photos will be blury or art, just like everything NASA has shown.

  • camryn

    why isnt pluto a planet? one of the most iconic cartoon dogs is named after it! and just because its smaller than all the other planets and hides in the back doesnt mean we should forget about it or give it a demeaning name! if our solar system was high school would you want the smaller kid in the back being called a dwarf!? i mean it has been a planet for hundreds of years and all of a sudden earth becomes the big bad bully and says its not a planet! i mean im no scientist, and this may just be another read over usless opinion but it shouldnt be changed and if i had a vote i would say no! because it deserves every right as the other planets i mean what happens if our planet becomes the smallest would we be casted out to? i just think that pluto should have the right to be a planet!

  • Oz

    We’re on the cusp of something truly amazing, and yet all we can do as human kind is argue the semantics of science in the comments section on the Discover Magazine website. This is why we haven’t evolved past what we are as a species, because we’re too busy arguing and fighting with each other all the time. This month we’re finally going to see what Pluto looks like and begin to understand what’s going on out there. Can’t we just be happy with that and forgo all the arguments? Surely science transcends needless aggression and competition? We all want the same thing after all, the facts. Human kind could spend years arguing over whether or not a Jaffa Cake is a biscuit or a cake, but it gets us nowhere. Whilst everyone will have an opinion, why accuse each other of things that only serve to get in the way of the real subject here? And that’s the fact that we’ll be seeing Pluto soon! I hope on that day you can all shake hands and just enjoy the moment. I know I’ll be enjoying it anyway.

  • Caseas

    < ?????? +dilbert +*********…..


  • kcwookie

    With no disrespect to anyone, there are some true facts that exist, very few, but some. One of them is that there are lies, damn lies, and statistics. The issue of how many planets we have was decided based on the criteria of what is a planet. That criteria was decided by in international committee. That committee had humans on it so it was biased. Humans are fixated on labeling thing. Labeling things allows them to create sets and other types of groups. Humans are the same species that decided that if someone who resembled other humans, but had too much skin pigment, they were then only ⅗ of a person. We are fixated with criteria.

    The Greeks were probably on of the first to define what a planet was and that definition would include Pluto…and the moon, asteroids, and much of what is out there. The Greek definition was great for a millennium, the definition really started to break down in the latter part of the 20th century (a time based criteria also decided by humans). The problem came to a head in 2005 when a planet had to be redefined or the definition enhanced. The results were published in 2006 and didn’t include Pluto. All the esteemed scientists posting here can defend this to whatever degree they wish, but with the all the new discoveries a new criteria had to be developed for whatever reason motivated them. Regardless of what the minutes show it is only logical that Pluto was sitting on this human created bubble. As has been published here, some of the scientists here are trying to claim that there is nothing wrong with being a dwarf planet, so if there is nothing wrong then why not consider Pluto a planet and add dwarf status to gas giants and terrestrial planets? That was obviously not going to fly because it would upset the nice orderly scientific criteria in place. It was decided to limit the number of planets at the adult table to 8 and relegate all the new discoveries to another table. Could the real problem be that we are running out of Greek and Roman God to name the planets after so removing them from the planet club meant that a new naming criteria (there’s that word again) be developed.

    Bias comes through all the time. Look up Ammonia, you will find it’s legally a non-flammable gas, but when you look at the properties of the gas, you will see that it has an upper and lower explosive limit, so that means it burns (flammable). The problem is that we can’t let Ammonia be flammable, it’s a PR disaster (much like the Pluto decision), Ammonia mixed with water is a cleaning agent and more importantly a fertilizer. How would Mr. and Mrs. America feel about feeding bread made with wheat that was fertilized using a flammable gas to their children? We all know the answer to that one, and hence we have a new criteria popular in the grocery stores…organic, which means it’s healthier than non-organic. There is no problem we humans can’t make go away by changing the criteria so that we can have it our way. 

    We have defined a criteria based on the needs of science in 2006; pretty egotistical given how little we know and the short time frame  we as a species have been observing. We inflate that ego even further given that the average life expectancy of an astronomer/cosmologist is about 85 years. The orbit of Pluto is 248 years so all these decision have been made by humans who haven’t even watched the sphere make one full trip around the Sun, how do we actually know it doesn’t clear the neighborhood, and by the way, neighborhood is a criteria defined by humans too. 

    Egos are the crux of the whole problem. Humans created a criteria to exclude Pluto and other dwarf planet, but we kept the terrestrials and the gas giants, I guess they had trouble counting above eight. Gas Giants and terrestrials are clearly different since it’s postulated that Jupiter would float if we could somehow float it in water. Why don’t we have 4 planets, 4 gas giants, and 3 plus dwarf planet making the population of our little solar system 11? The answer to that one is simple…scientific criteria (Latin for I don’t want to). 

  • Simiyu

    So, is Pluto, in fact, the only planet that is no longer considered to be a planet?

  • Tim Buckley

    so Pluto is still a planet, right ? it is a dwarf planet but still a planet (ie the word dwarf is used an adjective meaning small). So it is small and now we are calling it small, hmmmmm… I hope that the term dwarf is politically correct to Plutonians.

  • ohioborn30

    Pluto haters… What they don’t like dogs? Now that I have the joke out of the way Pluto should be listed as a planet.

  • David J

    Neptune hasn’t cleared pluto out of its path

  • Shar

    Pluto was always a planet to begin with. If gold was hidden does that mean its not gold? No it means that you are too dumb to look closer and see that it was gold. Well let me tell you pluto is that piece of gold. Before even discovered, PLuto was a planet no matter what you call it, Pluto was and always will be a planet.

  • Michael Mier

    Well, the New Horizons spacecraft flew by Pluto 3 days ago (July 14, 2015), and sent pics to Earth showing that Pluto has a young surface due to the absence of craters. I would assume this means that it has a magnetosphere as a result of a molten iron core. Should Pluto be reclassified as a planet. Well, it is spherical, orbits the sun, and has 5 moons. To boot, it is now considered to be the largest object in the Kuiper Belt. I’m hoping that the Pluto haters who demoted it in the first place will reconsider, and have our fellow planet deemed such.

  • jenny_brn

    Lets thumb our noses at the arrogance of IAU and declare Pluto to be a full planet.

    Pluto belongs to the US of A now and USA has the right to define her.

  • Muawiyah

    Trying to figure out WHO Pluto was hiding its secrets from 4.5 billion years ago ~

  • Francisco Salinas

    when i met astronomer Clyde Tombaugh, Pluto was a planet. Today it is still a planet … yes it is that simple.

  • Jef Cotham

    “I’m embarassed for astornomy,” said Alan Stern, leader of NASA’s New Horizon’s mission to Pluto and a scientist at the Southwest Research Institute. “Less than 5 percent of the world’s astronomers voted.”

  • EKMcM

    I tried to send message of encouragement to Pluto but it got sucked up by the heavy pull of Jupiter – isn’t there a law against that ?? ‘No message-napping’ or something like that ???

    • CheeringForAmerica

      As of right now there is no law that trumps the law of attraction (gravity).

  • Marc Sainte-Marie

    Love the Title: Pluto a Planet Again? It May Happen This Year.
    Anything can happen with Science, apparently IT is not all knowing, some even say its the search for Truth or Reality, stuff comes and goes, how fast depends on resistance from status quo politics.. yes yes “scientists” are very human creatures, may they believe they apes or not.
    “No planetary scientist “hates” anything.” ..I wonder about THAT, other ones do have hates.
    “…Such a condition would imply that we occupy a unique position in the universe, analogous, in a sense, to the ancient conception of a central Earth…This hypothesis cannot be disproved, but it is *unwelcome* and would only be accepted as a last resort in order to save the phenomena. Therefore, we disregard this possibility…. the unwelcome position of a favored location must be avoided at all costs…. such a favored position is *intolerable*…Therefore, in order to restore homogeneity and to escape the *horror* of a unique position…must be compensated by spatial curvature. There seems to be no other escape.” (Edwin Hubble, The Observational Approach to Cosmology)

  • Scarlett Bean

    The problem I find in this article is that Pluto does not fit the description of a planet. As agreed upon by the IAU a planet must have the gravitational capabilities to clear it’s neighborhood. Pluto can not do that so it is no a planet. These are the simple facts and the fact that Earth “might” not be able to clear it’s neighborhood is only a speculation, and even if Earth had a neighborhood to clear, and it was incapable of clearing it, so be it. This brings me to my second issue. Why does it matter whether or not a celestial body is a planet? It is merely a title, and no additional things are given to a celestial body with its classification being a dwarf planet. People are getting so bothered by the fact that Pluto’s planetary status was revoked they have not stopped to think why they really care. To be or not to be a planet, the immortal question that doesn’t really deserve an answer. Call me a Pluto hater if you must but there is not a single reason for why Pluto needs to be a planet, and not a dwarf planet. My speculation would be that people wanted something to feel self righteous about since they feel personally deprived of something and so they took out their own greediness out on the fact that Pluto has been placed in a sub category of planet that fits it better than the grand title of planet. And as a final note, for the scientific definition of clearing it’s neighborhood, In the end stages of planet formation, a planet (as so defined) will have “cleared the neighbourhood” of its own orbital zone, meaning it has become gravitationally dominant, and there are no other bodies of comparable size other than its satellites or those otherwise under its gravitational influence.


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