My contest goes to 11

By Phil Plait | February 28, 2008 10:30 am

First, I will make a caveat. Then, I will froth. Then, I will find the silver lining which makes this all better.


This is a delicate situation here. I love kids, and I love kids who love astronomy. I want to foster that love, and turn it into a lifelong interest in the sky, in astronomy, and in science.


So having said that, what the heck was National Geographic thinking?

They held a contest for kids to come up with a mnemonic, a memory-aid device, to help them remember the order of the planets. Like, My Very Excellent Mother Just Served Us Nine Pizzas, which is the one I heard when I was younger.

I’m all for this. That’s a great idea. Except… in the rules it says this (emphasis mine):

Compose a mnemonic (memory trick) using the first letter of each of the planets in order from the Sun (Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, Eris) as the first letter in a word. The words must make a fun and memorable English sentence (Example: My Very Excellent Mother Can Jump Slowly Under Nelly’s Plastic Elephant.)

Um, NatGeo? I hate to break it to you, but our solar system, officially, has eight planets. Pluto was kicked out years ago. If you want to be a Luddite and still accept Pluto as a planet, that’s fine, but really, Ceres and Eris too?


Eris is an object similar to Pluto, but slightly bigger and more massive, well out past Neptune’s orbit (objects there are usually called Kuiper Belt Objects or KBOs). While it fits some of the new definitions of a planet, it doesn’t clear out its neighborhood of smaller objects (it’s too small, and the space it occupies out in the hinterlands of the solar system are too voluminous), and that’s one of the rules planets follow.

Same with Ceres, the largest asteroid. With thousands, millions, of asteroids in the same region of space, Ceres doesn’t hack it either. Besides, all three objects (Ceres, Eris, and Pluto) are smaller than our own Moon. If you include those three, there will be dozens more, hundreds more, you have to include as well. You might even have to include Pluto’s moon Charon (note; some of the things I said in that post were superseded by later rules imposed by astronomers on the definition of a planet).

So in the end, NatGeo would have done a lot better to leave Ceres and Eris off — they’re just not planets by anyone’s definition — and to be consistent they should have left Pluto off as well.

Silver lining:

Having said all that, I want to heap praise on the ten-year-old girl won the contest. The phrase she came up with is excellent:

"My Very Exciting Magic Carpet Just Sailed Under Nine Palace Elephants."

It’s cute and it’s memorable (and it certainly follows the rules of the contest).

And in reality, what is very cool about this is we now have a little girl out there in Montana who not only knows the order of the planets, but she also knows a little something about asteroids and KBOs, too. How many ten-year-olds can say that? And I wonder, what’s in her future? Maybe eventually she’ll take an interest in the planet-naming controversy and help settle it. Maybe she’ll grow up to be an astronomer who discovers Earth-like planets orbiting other stars.

Where will her interests lead? For now at least, they’ve taken her billions of kilometers to the edge of the solar system, and for that, I am glad, and I congratulate National Geographic on holding the contest and doing something terribly, terribly important: igniting a spark for science.

Tip o’ the Whipple Shield to BABloggees John Phillips, Jeromy Labit, and Richard Velez for emailing me about this!


Comments (67)

  1. hale_bopp

    When Pluto got kicked out, I saw one disgruntled person (I forget who) came up with a great one…

    Many Very Egotistical Malcontents Just Screwed Up Nomenclature.

    That one cracked me up!

  2. “that’s one of the rules planets follow.”

    At least until August 2009…

  3. Randall

    I’ve said it before, and I’ll say it again: the only proper mnemonic in this post-Pluto age is as follows

    My very excited mother just sent us NOTHING.

  4. Michelle

    @Hale_Bopp: HA!!! I’m using that one from now on.

    In french we had our line too… “Mon vieux tu m’as jeté sur une nouvelle planète”… Now that one doesn’t work too either. And it’s not a bad thing, because I always thought as a kid that this was the most retarded line. I mean, I knew the one in english. It spoke of pizza. That was awesome. Ours spoke of a dude that threw another dude on a new planet. That’s lame.

  5. Todd

    What ever happened to Sedna? Shouldn’t NatGeo have included that, too?

  6. Melusine

    I quizzed my niece and her friend about the order of the planets when they were 11 and they did not need a mnemonic. When I raised my eyebrows after Neptune, I got a wag of the finger and she said, “Nuh uh uh, pluto isn’t a planet!” So, they learned that in 6th grade (at a Catholic school, btw.)

    Off topic: Her current science teacher is strict. When she skipped a line on a test, she got 50 points off, which I think is harsh for a minor thing. The teacher said that in real life there are consequences for such mistakes (like messing up with the metric system?). I was thinking, hey, don’t turn these kids off from science. They also learn about gas and matter in kindergarten, which was not my experience at all.

    Her mnemonic is cute though.

  7. SkepticTim

    Now, now Phil; Ceres, Pluto, Sedna, and Eris are all dwarf planets now! Do I detect a hint of dwarf planet apartheid here?

  8. What’s wrong with including dwarf planets in the mnemonic? Seems like a diplomatic solution to me, and the IAU currently only recognizes Ceres, Pluto and Eris as dwarf planets. Once Charon and Sedna and all those other crazy TNOs get grandfathered in, we could have a very complicated mnemonic indeed, but in the meantime let’s just congratulate little Maryn on her clever turn of phrase. Lisa Loeb’s supposedly going to even write a song using the mnemonic as part of the prize, which is probably pretty cool for a ten-year-old girl.

  9. Diogenes

    Don’t forget the Annnunakian equivalent:

    Many Vile Evil Men Cruelly Judged Sitchen und Nancy Patently Egregiously Negative

    (including Nibiru)

  10. Diogenes

    (Dang, stripped out the <snark> tags I’d put around that…)

  11. gopher65

    Uh BA, that’s because the IAU is made up of imbeciles who misdefined the word planet. I hope that in a few years that STUPID definition gets overturned. That definition is so odd that it is possible to alter Earth’s orbit and then have it be declared a non-planet. Whether something is a planet or not should have nothing to do with its orbital state.

    *kicks the IAU in the nads*

    Here’s what the IAU should have decided:

    1) “Classical Planet” – The 9 planets defined in a classical sense. Before this point the word ‘planet’ had no exact meaning, so these planets are defined as nothing more than “this is what people use to call planets”. This applies to only those 9 specific objects, and only to the Sol system. It exists for linguistic and historical purposes only, holding no scientific meaning.

    2) “Planet” – An object that is gravitationally bound to a star that is:

    i) large enough to be approximately spherical due to its own gravity.

    ii) small enough that it is incapable of undergoing deuterium fusion.

    (values of mass and “sphericalness” would be given exactly)

    3) “Rogue Planet” – an object that meets the above criteria but is not gravitationally bound to a star.

    4) “Gas Supergiant Planet” – A planet large enough to engage in shortlived tritium fusion, but nothing beyond that.

    5) “Brown Dwarf Star” – A planet-like object that is massive enough to undergo long-term deuterium fusion, but incapable of hydrogen fusion. Similar to, but larger than, a Gas SuperGiant.

    … and other definitions of Terrestrial Planet and Gas Giant that we currently have.

  12. Quiet Desperation

    Why do people need a mnemonic for this?

    Oh, and Plutophiles are LOSERS! 😉 Get over it. Man, you’re worse than the “Al Gore won” crowd. 😀 [/troll]

    The teacher said that in real life there are consequences for such mistakes

    Oh, geez, I had a teacher like that in Junior High (Middle School to some of you). You know what that is? It’s an adult competing with teenagers because they can’t compete with other adults.

  13. mike burkhart

    face it many people lust love the planet pluto even if it is not a planet

  14. Michael Lonergan

    Hmmmmm, this 10 year old girl lives in Montana? Isn’t Montana the place where Star Trek lore says Warp Drive was invented by humans? Maybe, just maybe….

  15. Melusine

    Mike said: face it many people lust love the planet pluto even if it is not a planet

    Yeah, I lust love over Mars. (-;

  16. I really don’t understand what’s so bad about having a zillion planets. It’s not like we’d really have to memorize them all. We have a zillion stars, and no one asks us to memorize all of them… even the most obsessive amateur might pick 25 of the brightest or nearest and be perfectly content. And even reference books stop at 100 unless they are the size of rooms.

    Secondly, Pluto not being a planet is hardly settled. The whole notion of “dwarf planet” is linguistically malconstructed. I mean seriously, it’s not SUPPOSED to have anything to do with their size, and here Phil is talking about how they are too small. And what will you do if a hypothetical KBO the size of Mars is discovered (such an object has been predicted). The current nomenclature will call it a “dwarf planet”, and will it still be too “small” if it’s the size of Mars? And what makes Mercury big enough? I mean, it’s just a rock, right? Why this magic cut-off?

    Planet was perfectly fine, like species or language, with some vague definition and everyone “knew” what it was. Now they’ve just gone and mucked it up. So until someone gives me a GOOD reason to think Pluto and Eris aren’t planets, they are still going to be planets to me. I don’t have any weird snobbery about planets being “special” which is what I think this whole controversy comes down to. At least they both have moons.

  17. I maintained, starting back in the ’80s, that Ceres should be counted as the planet between Mars and Jupiter. Indeed, I got reprimanded for it by an anonymous reviewer from Icarus.

    I like the 11-planet system (eight planets, three dwarf planets) because it preserves the spacing ratios nicely. If you leave out Ceres, you have this huge, weird gap between Mars and Jupiter. (Okay, in terms of mass, there really is a huge, weird gap between Mars and Jupiter, but it’s the principle of the thing.) And at 67 AUs, Eris is neatly positioned outside Pluto at 40 AUs. (I’m talking semimajor axis, not present distance.) The 11-planet system lends itself to “improved” versions of Bode’s Law.

  18. madge

    I get so sick of arguing with folk that Pluto is, was and never could be, a planet! SHEESH! C’mon Nat Geo get real!

  19. madge

    – My Very Educated Mother Just Served Us Nachos – will do just fine!

  20. Aerimus

    Wow, my contest only goes up to 10. Must be nice to get that little extra push over the cliff.

  21. K

    THANK YOU!!!!!
    I blogged that the other day as a total WTF moment.
    As in, WHEN did Pluto officially go back to being a planet?
    WHEN, officially, did a couple of asteroids make it to planet status?

  22. pjb

    Did no one pick up the titular reference to This is Spinal Tap?

  23. LarrySDonald

    I memorized them by rote around 5 and also got into arguments by claiming pluto wasn’t a *real* planet – not that I refused to list it but just, well, that’s one screwed up orbit for a planet to have.

    Now, I seem slow reciting them because I have them in rote in the wrong language, my brain recites them in the other language internally and then I translate them, stumbling slightly. It’s the same with the first 15 decimals of pi, I know the words to say them in the wrong language and then stumble because I forgot where I were when saying them in english.

    I prefer mnemonics with *two* first letters though (yes, I’m that scatterbrained – need more then one letter for clues) like “Men very easily make cement, juniper sauce urges net plot errors.”. I do better with less reasonable sentences but which provide additional clues when going “J.. j.. what starts with J again?”.

  24. Aerimus

    I’m always surprised to hear so many people with scientific minds stand so hardcore on Pluto. I mean, is not part of the scientific process that we adjust based on what we see? That said…

    Someone early said something about keeping Pluto as a planet until there was a good reason not to do so. I always considered that the “good” reason to dismiss Pluto as a planet was that it really more at home with another classification of bodies, KBOs, given it’s location, composition and orbit, just as Ceres fits the classification of asteroid particularly well. Just my two cents.

  25. Aerimus


    Yes, see the comment two above yours.

  26. pjb

    Whoops, missed that one. I gotta work on those reading skills…

  27. themadlolscientist

    What, no Quaoar? No Ixion? We wuz robbed! (As if losing Pluto wasn’t enough of a planetary ripoff.) And what would we call two more or less equal-sized spherical things orbiting each other?

    @Eric: =ROFLmeow!= Any objections to my posting it to LOLScience on flickr?

    @gopher65: I’m with you all the way!

    While we’re at it, what’s a “moon”? WTF, Saturn now officially has what, 60 of ’em? most of which have names that look like a rack of Scrabble letters.

    Tarqeq? Jarnsaxa? Ijiraq? Kiviuk? Bebhionn? Paaliaq? (Personally, I think “Bergelmir” and “Fornjot” are kind of cute.) I can’t wait to see what they call the eight or so that don’t have names yet.

    How small can a piece of rock get and still be a “moon”? Or a “dwarf planet,” for that matter?

  28. WJM

    My Very Educated Mother Just Showed Us Nine Planets.

    It was a very rare conjunction, and she has a killer telescope.

  29. What happened to Sedna? When it was discovered a few years ago, it was billed as the tenth planet. Then Pluto got kicked out, and suddenly it seemed like the whole dang solar system went to sh*t. And is it a coincidence that it happened during Bush’s presidency? I think not.

    I need one of those “Honk if is still a planet” bumper stickers.

  30. Oops. That bumper sticker actually reads “Honk if Pluto is still a planet.”

  31. Aerimus


    I love the fact that the Cafe Press URI ends with “keepplutoaplane”. When did anyone make Pluto a plane?

  32. Dadoo

    Ten years old? Wow.

    I thought my son was a little behind, because he couldn’t name all the planets until after he was four. Now he’s almost five, and he can tell you something about all of them – which one’s the hottest, which one’s the largest, which ones have rings, etc. (He knows a few of the elements and a lot of states, too.) If my wife and I were obsessive parents and spent all day forcing him to learn, I’d think we should ease up.

    One of his favorite things to tell my wife is “I love you all the way to the Andromeda Galaxy and back.”

  33. David Taylor

    Don’t forget that the IAU’s highly political taxonomy of planets not only is inapplicable beyond our solar system but also, applied consistently, demotes Jupiter, which is apparently “unable” to clear the trojan asteroids from it’s orbit. Someday, everyone but flat earther’s and disgruntled planetary dynamicists will get used to the idea of thousands of planets.

  34. My Astronomy lecturer at Uni in the 90’s used to deduct points if we said Pluto was a planet in quizzes and exams. Yeah there are probably hundreds of planets out there if you don’t want to take the strict abriarty (sp) route that IAU did but I’m not too fussed because at least the kept the mnemonic fairly simple to learn.

    At school we were taught, “Mrs Vokes eats many jam sandwiches until nearly pops” which was very memerable for us as we had a very rubenesque (sp) maths teacher called Mrs Vokes.

  35. Ginger Yellow

    “Don’t forget that the IAU’s highly political taxonomy of planets not only is inapplicable beyond our solar system but also, applied consistently, demotes Jupiter, which is apparently “unable” to clear the trojan asteroids from it’s orbit.”

    That’s hardly fair. You’re not supposed to be able to clear objects at L4 and L5.

  36. Joe Meils

    I guess I’m a luddite, by your definition.

    Yes, I love Pluto. It’s the only planet discovered by an American.

    It’s large enough to be sphereical.

    It has three moons.

    It circles the friggin sun

    It has a detectable atmosphere (when it’s not frozen)

    It would upset a bunch of european astronomers if we continued to call it a planet.

    Somehow, I don’t think this topic has been settled yet. In 12 more years, when Far Horizon arrives there and (we hope) gets a few good photos of some of the last terra incognita the solar system has, I think the argument will be renewed.

  37. BA:
    It appears that the Nat Geo was using the preliminary definition which got voted down- see my commentary in the post My Very Endearing Mother Certainly Just Shot Up Near Prison Cell 2003

    As for the cleared orbit angle, Hal Levison at the SW research institute handwavingly paramaterized this new definition here:

  38. Miranda

    My son knew the planets by rote before the age of 4 as well. He used to recite them at bedtime (in lieu of prayer … haha!).

    I was pretty proud, until I realized he didn’t know the names of the months in order. And was iffy on the days of the week. And couldn’t name the 10 provinces.

    Oops … :)

  39. Dadoo

    Something just occurred to me: this article is about a *girl* who’s interested in science. We probably shouldn’t discourage that. Granted, she probably isn’t going to read this web page, but just in case…

    Good job, Maryn!

  40. Isaac Asimov stated that the Solar System consists of “four planets plus debris” (often misquoted as “Jupiter plus debris”, which I prefer). So that’s that.

    But apart from that, I’m with Betsy on this; we have names for hundreds (thousands?) of stars, so why can’t we have dozens or even hundreds of planets? If it’s spherical (more or less), and goes round the sun, it’s a planet. Knowing their order really isn’t as important as knowing that they exist at all as far as children’s education is concerned, and anyway if we keep changing our minds about things like this, it only gives ammo to the Anti-Science brigade who say “See? The scientists are always changing the facts! So it’s obviously all made up.”

    Anyway, I wrote some music about Pluto and Charon, so it stays a planet in my book. It’s part of the culture, so it has to be.

  41. Charlie in Dayton

    My Very Easy Mnemonic Just Sits Unpoetically Now…

  42. MichiMatt

    Ceres and Eris are cool chunks of matter. I mean, they’re not the greatest, but they’re worth making kids learn about for all the reasons they’re NOT “planets”. There’s no reason kids can’t handle the idea of KBOs and the asteroid belt between Mars and Jupiter. Named objects put a friendly face on astronomy (something humans have been doing for thousands of years). The factoids associated with them are also the kind of stuff kids eat up.

    Seriously, we’d better stop being lazy on Earth. I’m sure there’s kids orbiting some distant star who have to memorize 20+ planets with far more confusing properties.

    Let’s cherish the star-crap we have, it’s all we’re gonna get out here.

  43. While we’re on about roundness, shouldn’t non-round moons be dwarf moons? Or moonlets? Otherwise, once we gain the ability to resolve ring particles things will get silly…

  44. Walabio

    I hate the exclusion of round objects of planets. Basically, they could not hope to memorize all of the planets, so they exclude most of them. The best thing is that if one considers a moon as some fitting the round part of the definition but orbiting the another planet. This would nicely tell us when to stop. If not, then we shall have to name the gzillions of chunks of ice in the rings of Saturn as moons.

    We do need mnemonics any more. We needed them before we could visualized planets. Back then, planets were nothing more than a list of names. Now, planets are worlds. When I heard Neptune, I see Neptune in my head. Just show the children pictures about the planets as they learn them. Frankly, these meaningless mnemonics are harder to remember than just imagining the Solar System on a logarithmic scale with a picture of each planet enbiggened logarithmically. That is what I do.

  45. Jeffersonian

    I live on Ceres and support your “National Geographic”. You should, too, as they are your food source (if our studies are correct). Please forgive any mistakes, we just got the internet this week and my eye transponder is still buggy.

  46. Lab Lemming:

    Hal Levison made an error in the first sentence of his paramaterizaion of the definition. According to the IAU, a planet is a celestial body that:

    – is in orbit around the Sun,
    – has sufficient mass so that it assumes a hydrostatic equilibrium (nearly round) shape, and
    – has “cleared the neighbourhood” around its orbit.

    Levison rephrased that third part of the definition as an “object large enough to clear its neighborhood of small bodies”.

    The problem is that the IAU used the past tense (that the body has already cleared the neighbourhood), whereas Levison is stating a potential (that it possibly could).

    According to the strictest interpretation of the IAU definition, there are only two planets in the universe: Saturn and Uranus. Extrasolar planets are not planets, because they don’t orbit the Sun. Mercury, Venus, Earth, and Mars have not yet cleared their neighborhoods of asteroids. Jupiter has trojan asteroids. Neptune has not cleared Pluto from its orbit.

    My new mnemonic is therefore: Silly Universe!

  47. Timothy

    I prefer Stephen Colbert’s mnemonic:

    My Very Educated Mother Just Said “Uh-oh! No Pluto!”

  48. Quiet Desperation

    It’s large enough to be sphereical. It has three moons. It circles the friggin sun

    So did my very fat and very late aunt, but we didn’t call her a planet.

    We called her “the human eclipse”, but never a planet.

  49. Ed,
    Cleared to what degree? All of the planets have comets cross their orbits, and are constantly plowing through zodiacal dust. And solar wind.

    And the Levinson equations tell how long a planet ought to take to clear their orbits. He solves for the current age of the solar system.

    And isn’t “forcing into a resonant orbit” the same as “clearing”?

  50. Roldy

    AWESOME! Spinal Tap reference BA – love it 😛

  51. Well, that’s sort of the point, LabLemming. The IAU’s definition is extremely vague, and includes terms like “clearing the orbit” that mean less than the term “planet” used to mean. In their zeal to exclude Pluto from the definition of planet, they have made the situation even worse than it was before. If one follows the letter of their definition, then even frikkin Jupiter isn’t a planet anymore, nor are the 275 or so extrasolar planets found thus far.

    Gopher65’s definitions are much better.

  52. Michael Lonergan

    Hey, Ed, I guess my cousin Vinnie the Cleaver is a planet. He clears the neighborhood.

  53. defectiverobot

    Hate to break it to you, but Pluto is too a planet.

    The mobile in my son’s bedroom says so.

    You try telling him otherwise.

    (Dadoo, I know exactly where you’re coming from.)

  54. Aerimus

    I have to agree with Ed here. The IAU’s definition just made things worse, not better. I think having a strict definition of planet makes no sense, since any definition that we make will result in some object, somewhere eventually being so close to the line between planet and something else that people are going to want it to be changed.

    As I’ve already said, I think the IAU’s decision to “demote” Pluto is warranted, as it really does appear to be a KBO, just as Ceres was reclassified as an asteroid in 1802.

    @Elwood: ‘…and anyway if we keep changing our minds about things like this, it only gives ammo to the Anti-Science brigade who say “See? The scientists are always changing the facts! So it’s obviously all made up.”’

    But that’s part of science! Updating and changing old ideas to represent a better understanding of the data is supposed to be central in scientific pursuit. When Pluto was discovered, it made since to call it a planet. But as time has gone on, we’ve discovered that Pluto isn’t this lonely little odd planet at the fringe of the solar system, but instead, part of another class of objects. Is it still worthy of recognition and the money it takes to study it? Heck yeah! But refusing to accept that Pluto really fits into the KBO classification better then the planet classification just because it clashes with existing world views? Isn’t that the kind of thinking that people like BA are fighting when they speak out against the Anti-Science brigade?

  55. David Taylor

    Aerimus:”Pluto really fits into the KBO classification better then the planet classification”. The dubious assumption being that it couldn’t possibly be in both classifications. I have no problem with the term “dwarf planets” as long as it also includes Mercury, Venus, Earth and Mars. That’s where the obvious size break occurs, and isn’t the word “dwarf” about size?

  56. Boba Fett

    How about: “my very enormous member can jam sperm under nancy’s puffy exit.”

  57. tim

    Here in Seattle, we’re having some kids enter a persuasive essay contest for a “Pluto IS a Planet” rally:


    On Saturday, March 15th, 2008 from 4-5PM, 826 Seattle and Greenwood Space Travel Supply, located at 8414 Greenwood Avenue North, are protesting the 2006 International Astronomical Union’s reclassification of Pluto as a “dwarf planet.” This event is free and open to the public.

    826 Seattle is the city’s only writing center entirely dedicated to helping students, ages 6 to18, improve their written communication skills. All 826 programs are structured around the belief that great leaps in learning can happen with one-on-one attention and that strong writing skills are fundamental to a young person’s future success. With the help of hundreds of volunteers, 826 Seattle offers free after-school tutoring, special writing workshops, class field trips, in-school programs, and publishing opportunities for Seattle students to improve their ability to communicate effectively in writing. 826 Seattle is supported in part by the Greenwood Space Travel Supply storefront.

    The “Pluto IS a Planet” protest march and rally is the culmination of a two-day persuasive writing workshop geared towards youth ten years and older. The march begins at The Greenwood Space Travel Supply Co., travels north on the sidewalks of Greenwood Avenue to 87th Street, and returns south at Neptune Coffee, located at 8415 Greenwood Ave North. At the rally, before a panel of experts, workshop participants will read their persuasive arguments as to why Pluto should be reclassified as a planet. Experts include professional persuasive author, Seattle Times columnist Nicole Brodeur, professional persuasive speaker, lawyer Shawn Rediger, and local rocket scientist Tim Lloyd.

    # # #

    For more information, please contact Justin Allan, Store and Events Manager at (206) 725-2625 or go to

  58. Aerimus

    @David Taylor

    Yeah, Pluto could be defined as both, as well as Eris and Ceres. I just think that things as they are now work better when you consider Ceres to be an asteroid (based on size, composition and location relative to other asteroids), Eris and Pluto as KBOs (again, based on the same). Then Mercury, Venus, Earth and Mars as terrestrial planets (as they are rocky worlds in areas that are, relatively speaking, empty and located closer to the center what was once the proto-planetaru disk, where the heavier elements that make them up would be expected) and Jupiter, Saturn, Uranus and Neptune as the gas giants (with their own traits and characteristic that should be obvious).

    So far, the biggest reason that I’m always hearing as to keeping Pluto a planet is always more of a dogmatic answer rather than one based on observations or data (i.e. “Pluto will always be a planet to me!”). Maybe I’m just not listening to the right people, or the right people’s voices are being drowned out be the swaft of uneducated people who just cry “Pluto will always be a planet to me!” (as a Christian who believes in a figurative genesis and that religion should be changed to support science discovers, I know how that feels). Maybe when the essays in Seattle are done, they’ll post some. I think that it’s marvelous that they are getting kids to look at this critically, even if it is in opposition to my personal preference. I’m just hoping that the essays, at least from the high schoolers, have some real thought behind them.

    Some other things:
    1) Concerning Jupiter clearing out it’s orbit arguement – This is specifically why I think that the definition is poor or should be dropped altogether and we just look at all this planet crap on a case by case basis. Yeah, there as asteroids in Jupiter’s orbit which have not been “cleared out”, but they are being herded by Jupiter’s gravity. It’s clear who in control in Jupiter’s neighborhood.
    2) Yeah, if we want to pick nits, the definition only applies to the solar system. But come on! Like you can’t easily take this definition and use it when looking at other systems? Wow, that’s narrow minded.

    I think that the kicker question is this: If Pluto were found today, knowing what we know now about KBOs, would it be a planet? I doubt it. The only reason why Eris is being questioned about planet or KBO is because its larger that Pluto.

  59. Boba Fett writes:

    [[How about: “my very enormous member can jam sperm under nancy’s puffy exit.”]]

    I think Nancy may just slap you upside the head when you get home.

  60. Irishscribe

    When I was young, and the solar system was an orderly, simple place, I had a good one for remembering the order of the “classical” nine planets. Mount Vesuvious Erupts Mulberry Jam Samwitches Under Normal Pressure.

  61. Aerimus: Yeah, I noticed that about the URL when I pasted the link. I actually had to go back and make sure it was correct.

  62. Ronn!

    Um, Phil . . .

    “Pluto was kicked out years ago.”

    More like six months . . .

  63. Ronn!

    Oops . . . my brain slipped a digit. Try 18 months.

    (Though still not exactly “years ago” . . . )

    At least I got the August part right . . .

  64. National Geographic was thinking what the IAU should have thought–what makes linguistic and scientific sense, namely that dwarf planets should be classified as a subclass of planets. These objects are significantly different from the asteroids in that they have achieved hydrostatic equilibrium, meaning they have enough self-gravity to pull themselves into a round shape, giving them geological processes more akin to those of the classical planets. Many planetary astronomers concur with this view and oppose the IAU definition, which was coined by four percent of its membership, most of whom are not planetary scientists.

    At this time, when we are discovering more types of exoplanets than we could have imagined, we should be broadening, not narrowing the concept of planet. If that means we have 200 planets in our solar system, then so be it. Memorization is not as important as is understanding the characteristics of the different types of planets. So we could divide the broad term planet into subcategories such as terrestrial planets, gas giants, ice giants, dwarf planets, etc. Yet all would still be planets. This classification would acknowledge the significant differences between inert, shapeless asteroids, and objects like Ceres, Pluto, and Eris that have achieved hydrostatic equilibrium.

    Telling people to “get over” a decision we believe is scientifically wrong and was established by a closed, backroom process is ridiculous and nothing more than a personal attack, which is what people make when they have no arguments to back up their viewpoints.

    As for the 11-year-old in Catholic school being taught that we have only eight planets, she and her classmates are not getting the whole truth, which is a disservice to them. Children can understand that some debates remain open, that different experts can observe the same facts and reach different conclusions. Teaching only one view is teaching dogma, plain and simple. Schools should use this opportunity to help children learn that some issues are open-ended and have more than one answer and that the process by which decisions are made are as important as those decisions themselves.


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