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Thennews shocked the world. (Apparently.)
Thennews shocked the world. (Apparently.) n
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nKids cried. Adults grumbled.nPeople wrote irate Letters to the Editor. (Umm…really?)
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nAllnbecause poor little Pluto, so small and far away, and so incapable ofndefending itself, was kicked out of the planet family!
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nItnwas demoted to—gasp! the horror!—dwarf planet!!!
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nBacknon August 24, 2006, when the International Astronomical Union votednto relabel Pluto based on many new findings in astronomy, I nodded mynhead. New data often requires us to re-sort, re-categorize, re-label.nIt’s something to cheer, because it means we humans have learnednmore; we’re closer to achieving an accurate picture of the universe.
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Butnsome people got very upset! Some children sent hate mail tonastronomer Neil deGrasse Tyson. Legislatures of two states voted tonrefuse to recognize the IAU’s decision. People “yelled” at eachnother on the internet (and you know how rarely THAT happens!). n
Butnsome people got very upset! Some children sent hate mail tonastronomer Neil deGrasse Tyson. Legislatures of two states voted tonrefuse to recognize the IAU’s decision. People “yelled” at eachnother on the internet (and you know how rarely THAT happens!). nn
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nOnenof the reasons that some people got upset, apparently, is becausenPluto getting kicked out of planethood messes up the mnemonics thatnkids learn to remember the order of the planets in the solar system.nOne of the most common of these mnemonics is: “My Very EnergeticnMother Just Served Us Nine Pizzas.” (Mercury – Venus – Earth –nMars – Jupiter – Saturn – Uranus – Neptune – Pluto.)
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nButnthis is silly. For one thing, Pluto sometimes dips inside Neptune’snorbit, and making the sentence end with the words “served us pizzasnnine” sounds pretty goofy. (If Pluto were a planet, it would havenbeen the eighth, not ninth, planet from 1979 to 1999.) Also, surelynwe can easily come up with a new mnemonic? How about “My VerynEnergetic Mother Just Served Us Nachos,” or even “My VerynEasygoing Mother Just Served Us Nothing”?
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nIngather that it is Americans, and American school children, that gotnespecially upset about Pluto’s demotion. The guy who discoverednPluto, Clyde Tombaugh, was an American astronomer, and Walt Disneynnamed Mickey Mouse’s dog “Pluto” after the planet to celebratenthat discovery. Maybe a lot of people were upset by Pluto beingnkicked out of the planet club because it is the smallest planet (bynfar—it’s really tiny, even compared to the very small Mercury), andnpeople want to stick up for the little guy, and root for thenunderdog.
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nTonwhich some people have replied, “Why are you getting so upset aboutnthis? You don’t hear Pluto complaining, do you?”
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nAnd some people have pointed out that, it’s not as if Pluto were blown up, or ejected out of the solar system. It’s just where it always has been. We just have added the word “dwarf” to its category.
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nHmmm…sonwhat is a planet?
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nThenIAU was struggling with the question of whether or not to call somennewly discovered bodies planets. Eris, Makemake, and Haumea all orbitn far from the Sun, like Pluto, they’re spherical, like Pluto, andnsome of them are roughly the size of Pluto. If Pluto is a planet,nshouldn’t they be planets, too?
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nSo,ndoes the solar system have 10 planets? Or 12? Or more and more as wendiscover more and more?
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n(Ifnso, we’re gonna need a much bigger mnemonic!)
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nSomenscientists reasoned that Pluto and these other Kuiper Belt Objectsncould be considered a new sort of thing in the solar system. Insteadnof being the last and littlest planet, Pluto could be thought of asnthe first and one of the largest Plutoids (KBOs that are large enoughnto be roughly spherical in shape). n
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nSee,nit’s not a DEmotion, it’s a PROmotion! n
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nThendefinition of a planet is:
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nann object that circles a star (the IAU definition said “that circlesn the sun,” but that was a mistake that would leave out all of then planets we have discovered circling other stars)
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nann object large enough to be spherical
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nann object that has “cleared the neighborhood” around its orbit.n That would exclude the largest asteroids in the asteroid belt asn well as the largest Plutoids in the Kuiper belt. n
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nAlsonon this date:
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nIndependence Day in the Ukraine
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nAnniversary of the eruption of Mt. Vesuvius