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Roundest Object In the World Created

Posted by CmdrTaco on Tue Jul 01, 2008 08:19 AM
from the boobs-boobs-boobs dept.
holy_calamity writes "An international research group has created the most perfect spheres ever made, in a bid to pin down a definition of the kilogram. It should be possible to count exactly the number of atoms in one of the roughly 9cm silicon spheres to define the unit. Currently the kilogram is defined only by a 120-year-old lump of platinum in Paris, but its mass is changing relative to copies held elsewhere. Other SI units have more systematic definitions."
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  • Wishing... (Score:4, Funny)

    by AioKits (1235070) on Tuesday July 01 2008, @08:20AM (#24014621) Homepage
    Did anyone else read "An international research group has created the most perfect spheres ever made" and think boobs?
    • Re:Wishing... (Score:5, Insightful)

      by Rakshasa Taisab (244699) on Tuesday July 01 2008, @08:23AM (#24014653) Homepage

      I don't know what kind of ero-manga you've been reading (Ok, perhaps I do...), but real boobs aren't spherical. Especially not ones that would be anywhere near being considered 'perfect'.

      • by AioKits (1235070) on Tuesday July 01 2008, @08:26AM (#24014699) Homepage
        Ero-manga?
        • by veganboyjosh (896761) on Tuesday July 01 2008, @08:47AM (#24014985)
          You know, as opposed to the other kind of manga...
        • Re:Wishing... (Score:5, Informative)

          by _KiTA_ (241027) on Tuesday July 01 2008, @08:52AM (#24015061) Homepage

          Ero-manga?

          Ero-Manga is the proper term for what most clueless US fanboys call "Hentai Manga."

          Specifically, he was pointing out that some Ero-Mangaka ("Hentai Artists") draw breasts as if they were morbidly huge helium filled balloons floating on top of a woman's chest.

          All this in an attempt to state that you do not know what good breasts look at, having (apparently?) based your opinion on Japanese ero-manga anatomy.

          All this in a completely-missing-the-point of the "Heh, Boobs are Round, Scientists are Horny" joke he was replying to.

          ... Wow, geeky of me, eh? I do however, wish to go on the record that I fully support scientific efforts to find/create the perfect breasts.

          • Re:Wishing... (Score:5, Insightful)

            by somersault (912633) on Tuesday July 01 2008, @09:13AM (#24015385) Homepage Journal

            I do however, wish to go on the record that I fully support scientific efforts to find/create the perfect breasts

            If all women had scientifically 'perfect' breasts then those perfect breasts would get pretty boring, unless the scientific process took into account many different factors and created different breasts for each person. I think 'perfect' is all down to personal preference.

            There is beauty in many different breast shapes, though everyone will have their preferences. I think any slashdotter with access to any kind of breasts would be pretty happy. Apart from the female ones, they probably aren't too fussed.

    • by pzs (857406) on Tuesday July 01 2008, @08:33AM (#24014801)
      Did anyone *not* think that?
    • by efence (927813) on Tuesday July 01 2008, @08:40AM (#24014895)

      Did anyone else read "An international research group has created the most perfect spheres ever made" and think boobs?

      I have read "Roundest Object In the World Created " and immediately thought "CowboyNeal".

    • by Anonymous Coward on Tuesday July 01 2008, @08:46AM (#24014971)
      Did anyone else read "most perfect", and flinch?
      • by mattwarden (699984) on Tuesday July 01 2008, @12:24PM (#24018263) Homepage

        > Honestly, as a married man I don't understand why anyone would think that...
        >
        > My first thought was of more efficient ball bearings

        Thanks. I've printed this comment out and plan to show it to my friends when they bug me about why I'm not married.

  • by elrous0 (869638) * on Tuesday July 01 2008, @08:20AM (#24014627)
    No mere human will never be able to accomplish what God did with Jennifer Lopez's ass.
    • by Anonymous Coward on Tuesday July 01 2008, @08:28AM (#24014727)

      In a press release today, Sir Mix-A-Lot is quoted as saying that, by viewing this object, "You get sprung", as well as "[wanting to] pull up tough" because of the perfect shape of the object.

      He was later quoted as saying that "I like'em round and big, And when I'm throwin a gig, I just can't help myself". Clearly, he is an aficionado for perfectly round objects.

      * my captcha was "beating", which is what I deserve for the 90's reference.

    • by Sabz5150 (1230938) on Tuesday July 01 2008, @08:45AM (#24014935)

      No mere human will never be able to accomplish what God did with Jennifer Lopez's ass.

      Perhaps not, but we are interested in pinning down the exact measurement of the kilogram, not the metric ton.

  • Finally (Score:5, Funny)

    by Rik Sweeney (471717) on Tuesday July 01 2008, @08:22AM (#24014647) Homepage

    No one will be able to claim that a game of pool, snooker or soccer was won because the ball wasn't round enough...

  • What's the problem? (Score:4, Interesting)

    by Dolda2000 (759023) <(moc.0002adlod) (ta) (kirderf)> on Tuesday July 01 2008, @08:25AM (#24014687) Homepage
    I've never really understood the problem with creating a more stringent definition of the kilogram. Other SI units are measured in measurable quantities, such as the second being defined in terms of cycles of radiation from Caesium atoms. Why cannot the kilogram just as easily be defined as the mass of a certain number of atoms of one or another kind?

    Of course, I'm no experimental physicist, but if I were to guess, I might suggest the fact that the binding energy (and thus the mass) might change with force-field fluctuations in the vicinity, but I think that problem should be solvable by defining the proper environment for measuring.

    Does anyone know?

    • by joaommp (685612) on Tuesday July 01 2008, @08:31AM (#24014771) Journal

      That's precisely what they are trying to do.

    • by Zironic (1112127) on Tuesday July 01 2008, @08:31AM (#24014773)
      That is what they are doing. They are defining the kilogram as X silocon atoms.
        • by magarity (164372) on Tuesday July 01 2008, @09:05AM (#24015231)

          You can't calibrate a scale by telling it your theoretical model - at some point there actually has to be a physical thing.

            • by Waffle Iron (339739) on Tuesday July 01 2008, @09:28AM (#24015587)

              why not use, say, electrons, as in 1kg=weight of 1.1xxxe30 electrons (at rest)?

              They tried that, but when they charged their terafarad capacitor with 1e30 electrons so that they could calibrate their scale, somebody accidentally grounded it and the massive arc of current blew the roof off of the lab.

    • by icegreentea (974342) on Tuesday July 01 2008, @08:34AM (#24014833)
      You can define a kilogram in the number of atoms of X element, but you still need a physical object to calibrate your scales against. In this case, I believe they did it by number of silicon atoms. TFA says they went and milled a silicon sphere (purified to only Silicon-28) weighing as close to the current standard as they can get it. Next they're going to measure it (X-rays and the such) to find the density, spacing, and the such and end up getting a number of silicon atoms. This number will now BE the kilogram, and these spheres are going to be the new physical standards. They are suppose to be an improvement in that is it theoretically possible to recreate these spheres should anything happen to them (as we know the amount silicon needed), while it is not possible to recreate the current standards.

      My other summary was a bit off, got the process a little backwards.
      • by MrNaz (730548) on Tuesday July 01 2008, @09:19AM (#24015467) Homepage

        It's not totally worthless, as the kilogram is the basis for just about all other SI units. It is the only unit that is not defined according to other units, or in relation to a natural property. Thus, its definition is arbitrary, and everybody must agree as to what a kilogram is before the unit has any value as a standard. There's a very nice explanation of the kilogram as a fundamental unit here:

        http://en.wikipedia.org/wiki/Kilogram#Importance_of_the_kilogram [wikipedia.org]

        • by icegreentea (974342) on Tuesday July 01 2008, @09:07AM (#24015273)
          That's exactly what the TFA says. They've created two spheres made out of pure crystalline silicon (so now they've lined them up). The sphere is nearly perfect (its about 95mm in diameter, has small scale variations of 0.3nm, and deviations from perfect cruve of 60-70nm). Now they're going to independently measure 60 000 points of the surface of the sphere to map out all of the surface variations, and then they're going to measure spacing using X-ray crystallography.

          Also, nitpicking but... one kilogram = 10^15 picograms, always.
    • by Moraelin (679338) on Tuesday July 01 2008, @08:56AM (#24015117) Journal

      Well, it's sorta like this: a standard is only useful if you have some effective way to reproduce it or measure with it.

      1. time. You can essentially just make a MASER, which means basically a cavity which resonates at that frequency. The nice part is that it can be tuned, and even continuously tuned, by just measuring the amplitude of the signal. When you've reached the maximum power, the thing is tuned to that frequency.

      2. length. It's measured by Interferometry, so you have a meaningful way to transform a wavelength into any given distance.

      At any rate, the transition for these two only happened when someone build a device which could actually measure one second or one metre that way.

      3. mass. Well, that's the tricky one. Saying that you define a kilogram as one bazillion silicium atoms is useless unless you can somehow actually produce a lump with that many atoms. As long as we can't actually be sure how many atoms are in there, it would be a useless standard.

      These guys claim to have been able to do just that: say with a high degree of confidence that, yep, their spheres contain exactly that many atoms. If they're right, then we're finally ready to move the kilo to that standard.

        • by gnick (1211984) on Tuesday July 01 2008, @09:50AM (#24015889) Homepage

          So how do you define a pound?

          My driver's license (a legal document!) says that I weigh 185 lbs. So, 1 lb is defined as my weight divided by 185.

          Therefore, 1 kg = 2.20462262 * (1 gnick-weight) / 185. Was that so hard? A measurable quantity.

          The only problem I see is that I don't to live out my days on some shelf in France.

  • Cleanroom? (Score:5, Insightful)

    by lobiusmoop (305328) on Tuesday July 01 2008, @08:26AM (#24014705) Homepage

    The picture in the article shows the sphere being handled in what obviously isn't a cleanroom. Won't that mess up its surface?

  • Pong (Score:5, Funny)

    In other news... these same scientists are hosting the BEST GAME OF PONG EVER this weekend!
  • Metric... (Score:5, Funny)

    by jo7hs2 (884069) on Tuesday July 01 2008, @08:30AM (#24014753) Homepage
    So the metric system, which is touted as being so much more accurate than the measurements we here in the U.S. know and love is has a measurement that is based on a disappearing lump of metal? The only logical conclusion one can draw from this disclosure is that the metric system is magic, and should be burned at the stake.
  • by Anonymous Coward on Tuesday July 01 2008, @08:36AM (#24014847)

    So I'm not getting fatter, it's the kilogram that's getting slender!

  • by intx13 (808988) on Tuesday July 01 2008, @08:40AM (#24014903) Homepage

    An international research group has created the most perfect spheres ever made, in a bid to pin down a definition of the kilogram. It should be possible to count exactly the number of atoms in one of the roughly 9cm silicon spheres to define the unit.

    "First we create a perfect sphere, then we count the number of atoms exactly - and we get a kilogram standard!"

    "Alright... so how big do we make this sphere?"

    "Oh you know.. roughly 9 cm, give or take."

  • just add water (Score:5, Interesting)

    by krystar (608153) on Tuesday July 01 2008, @08:46AM (#24014949)
    why not just define a kg as 1 Liter of pure H2O at 4deg C?....it is that way anyway.
    • Re:just add water (Score:5, Informative)

      by Shados (741919) on Tuesday July 01 2008, @09:10AM (#24015331)

      Because its 1 liter of pure h2o at 4 deg C -at the sea level-, (remember, pressure isn't the same at the top of a mountain than it is at the bottom...and it changes everything). It is also not universal... if the earth was to go boom, (and somehow live), we'd lose our reference.

      That is in opposition to, let say, a meter, which is a fraction of the distance light travels in a specific amount of time. Fairly universal. (I beleive it USED to be a fraction of the earth's size... which was quite bad too).

  • I think that Gravity Probe B has the most perfect spheres and they are much smaller that the Kilogram sphere.

    Kilogram Silicon Spheres
    "If you were to blow up our spheres to the size of the Earth, you would see a small ripple in the smoothness of about 12 to 15 mm, and a variation of only 3 to 5 metres in the roundness"

    Gravity Probe B Spheres
    http://www.nasa.gov/mission_pages/gpb/index.html [nasa.gov]
    "If these ping pong-sized balls of fused quartz and silicon were the size of the Earth, the elevation of the entire surface would vary by no more than 12 feet"
  • by boristdog (133725) on Tuesday July 01 2008, @11:06AM (#24017023)

    The answer is none.
    None more round.

  • by fo0bar (261207) on Tuesday July 01 2008, @11:28AM (#24017347)

    It's 1024 grams, right? Easy definition.

    • Re:anyone (Score:5, Funny)

      by oahazmatt (868057) on Tuesday July 01 2008, @08:23AM (#24014661) Journal

      Does anyone here want to inform CmdrTaco that boobs shouldn't be perfectly spherical, and in fact, it's preferable if they're not?

      It's not his fault. He watched a lot of Baywatch. He doesn't know any better.

      • by wisebabo (638845) on Tuesday July 01 2008, @09:03AM (#24015201) Journal

        Is this really the reason why it's a sphere? Crystals don't PRECISELY grow into a sphere do they? Won't they still need to shave or polish it to get it to the exact radius? And then they'll need to calculate the number of atoms using Pi, an irrational number!

        Why don't they make it a cube and find a length that is close enough (cubed) to give them the approx. right number of atoms and then make THAT the standard? They'll then have an EXACT number of atoms making up each length. It should be easier to cut or shave off the requisite number of atoms to maintain it, a (perfectly) flat surface seems much easier to maintain than a 3D curved surface. In fact if they make it just a little too small they could probably even ADD to the cube in single atomic layers using vapor deposition!

        Obviously brighter minds than mine have thought this through more thoroughly, so really, I'm curious: why is it a sphere?

        By the way, maybe this is a good use for the ISS, to keep the 1kg reference MASS somewhere it won't be distorted by gravity, not kept at any particular country for measurement and you can keep it in a high quality vacuum for free! (A little expensive to get to though).

    • Re:Double Dupe (Score:5, Informative)

      by wvmarle (1070040) on Tuesday July 01 2008, @09:06AM (#24015257)

      Not a dupe - a follow-up.

      The first article mentions only the weight loss of the original kilogram, the second article follows up on that mentioning a perfect sphere is going to be made. The current article follows up on that, announcing the actual creation of this sphere.

      Now the fourth article in this series should be the announcement of the number of silicon-28 atoms needed to create exactly one kilogram.

      On the other hand, isn't the exact mass of atoms known? Then it should be easy to say "this number of atoms is exactly one kilogram". The creation of the sphere being an exercise left to the reader.

    • by srjh (1316705) on Tuesday July 01 2008, @10:08AM (#24016159)
      That's actually the reasoning behind the Watt Balance [wikipedia.org] another potential method for defining the kilogram.

      Keep in mind that the Joule is a composite SI unit, and is itself dependent on the mass of the kilogram. Unless you can calibrate the energy measurements (exactly what they are trying to do) you end up with a circular definition.