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Roundest Object In the World Created

CmdrTaco posted more than 6 years ago | from the boobs-boobs-boobs dept.

Science 509

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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first (-1, Redundant)

Anonymous Coward | more than 6 years ago | (#24014619)

first

Wishing... (4, Funny)

AioKits (1235070) | more than 6 years ago | (#24014621)

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

Re:Wishing... (5, Insightful)

Rakshasa Taisab (244699) | more than 6 years ago | (#24014653)

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'.

Re:Wishing... (5, Funny)

AioKits (1235070) | more than 6 years ago | (#24014699)

Ero-manga?

Re:Wishing... (-1)

Anonymous Coward | more than 6 years ago | (#24014979)

Is a 7337 neologism for Hentai used in the hentai scene. You use it when you want to look like you know Japanese.

Re:Wishing... (5, Informative)

Rakshasa Taisab (244699) | more than 6 years ago | (#24015143)

Please don't go around trying to be witty against people who don't just live in Japan, but also speaks the language.

Ero-manga is what they call it. If I wanted to talk about hentai, the really creepy kind of mangas, I'd have called it that.

Re:Wishing... (1)

xerxesVII (707232) | more than 6 years ago | (#24015215)

What is teet?

Wait, I'm asking that question in a thread where we're talking about boobs. Great.

Re:Wishing... (4, Funny)

veganboyjosh (896761) | more than 6 years ago | (#24014985)

You know, as opposed to the other kind of manga...

Re:Wishing... (5, Informative)

_KiTA_ (241027) | more than 6 years ago | (#24015061)

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... (0)

Anonymous Coward | more than 6 years ago | (#24015067)

At the old folks' home, they could be considered a series of tubes.

Re:Wishing... (3, Interesting)

maxume (22995) | more than 6 years ago | (#24014669)

CmdrTaco did. Look at the dept. line.

Re:Wishing... (1)

the_xaqster (877576) | more than 6 years ago | (#24014697)

All I can say is "What a load of Balls!"

Vague AC/DC Reference (4, Funny)

smitty_one_each (243267) | more than 6 years ago | (#24014951)

Your balls may always rotate
Deiseil or widdershins
What matters is their smoothness
Reflects what's on your chins.
Burma Shave

Re:Wishing... (0)

Anonymous Coward | more than 6 years ago | (#24014733)

Spherical boobs? :O

That would never work. The area of join twixt boob and body would have zero area and they'd fall off.

Re:Wishing... (2, Funny)

joaommp (685612) | more than 6 years ago | (#24014737)

Well, those spheres are made of silicon...

Re:Wishing... (4, Funny)

pzs (857406) | more than 6 years ago | (#24014801)

Did anyone *not* think that?

Re:Wishing... (4, Funny)

efence (927813) | more than 6 years ago | (#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".

Nope (1)

Saffaya (702234) | more than 6 years ago | (#24014943)

I actually thought "Extremely high precision Inertial sensor", the kind that is put in space probes or satellites, since perfect spheres are required for the gyroscopes IIRC.

Re:Wishing... (5, Funny)

Anonymous Coward | more than 6 years ago | (#24014971)

Did anyone else read "most perfect", and flinch?

Re:Wishing... (2, Funny)

MrNaz (730548) | more than 6 years ago | (#24015179)

Yea, but I've seen more worst cases of grammatical error on Slashdot.

Re:Wishing... (0)

Anonymous Coward | more than 6 years ago | (#24015141)

Silicon ?

The hubris of man (5, Funny)

elrous0 (869638) | more than 6 years ago | (#24014627)

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

In other news... (5, Funny)

Anonymous Coward | more than 6 years ago | (#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.

Re:The hubris of man (1)

Chineseyes (691744) | more than 6 years ago | (#24014777)

Or with Dave Chapelle's balls [youtube.com] FLASH LINK!!!! You've been warned.

Re:The hubris of man (5, Funny)

Sabz5150 (1230938) | more than 6 years ago | (#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.

Accept it before it destroys you (1)

Tonyrockyhorror (1132879) | more than 6 years ago | (#24015077)

You mean George Michael's butt. Look at it! [youtube.com]

anyone (2, Insightful)

gEvil (beta) (945888) | more than 6 years ago | (#24014635)

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

Re:anyone (4, Funny)

oahazmatt (868057) | more than 6 years ago | (#24014661)

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.

Re:anyone (1)

joaommp (685612) | more than 6 years ago | (#24014757)

He should know better, he's a geek and he got married...

Finally (4, Funny)

Rik Sweeney (471717) | more than 6 years ago | (#24014647)

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

Re:Finally (1)

Vectronic (1221470) | more than 6 years ago | (#24014873)

So... someone/thing creates the next stage in the lust for the perfect sphere, and suddenly every other sphere in existance is upgraded to this new standard?

Damn right they can complain, if anything it gives them more of an excuse - "I oh fuck that, i coulda made that shot if the ball was a ______"

I highly doubt more than one person would pay some $500,000,000 or whatever for a set of pool balls made in the same fashion as these were.

Yeah yeah, "it was a joke"...but... (What is

Re:Finally (5, Funny)

Jesus_666 (702802) | more than 6 years ago | (#24014981)

A soccer match with a ball made from solid silicon? Now that's something I'd pay to watch.

gravity? (1, Insightful)

Anonymous Coward | more than 6 years ago | (#24014651)

Doesn't gravity's effect imply that a perfectly round object could only exists in "gravity-free" (outer) space?

Re:gravity? (1)

pipatron (966506) | more than 6 years ago | (#24014955)

No.

What's the problem? (3, Interesting)

Dolda2000 (759023) | more than 6 years ago | (#24014687)

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?

Re:What's the problem? (5, Informative)

joaommp (685612) | more than 6 years ago | (#24014771)

That's precisely what they are trying to do.

Re:What's the problem? (1)

HEbGb (6544) | more than 6 years ago | (#24015039)

Then why are they wasting all of this time and energy making a physical "standard"? This reeks of agency PR.

Re:What's the problem? (1)

MrNaz (730548) | more than 6 years ago | (#24015241)

Because the French government funded them to keep the standards held relevant, lest people realize just how redundant they are in the face of modern platonic definitions of these units.

Re:What's the problem? (4, Informative)

Zironic (1112127) | more than 6 years ago | (#24014773)

That is what they are doing. They are defining the kilogram as X silocon atoms.

A little light. (-1, Redundant)

Anonymous Coward | more than 6 years ago | (#24014937)

That is what they are doing. They are defining the kilogram as X silocon atoms.

10 silicone atoms? Don't you think that's a little light?

Re:A little light. (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#24015217)

It's 1010, silly

Re:What's the problem? (0, Redundant)

multi io (640409) | more than 6 years ago | (#24015165)

That is what they are doing. They are defining the kilogram as X silocon atoms.

And why do they have to actually create a silicon sphere for that? Couldn't they just define some reasonable X and then derive the actual weight of the kilogram from theoretical models?

Re:What's the problem? (4, Informative)

magarity (164372) | more than 6 years ago | (#24015231)

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

Re:What's the problem? (0)

mspohr (589790) | more than 6 years ago | (#24014781)

Duh... If you RDFA you will see that this is what they are trying to do...

Re:What's the problem? (5, Informative)

icegreentea (974342) | more than 6 years ago | (#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.

Re:What's the problem? (1)

mapsjanhere (1130359) | more than 6 years ago | (#24015131)

The problem is, how to line up the silicon atoms(or whatever element you're using)for counting. A kg of silicon 28 contains some 2x10^22, give or take a few. And the few are the issue.
The second is defined as 9 192 631 770 swings per second. To be equally precise you need to get the mass of the kg right into the picogram scale. Or, if you do the math on the surface area of the ball, you need to be within 1 nm all around to be better than 1 nanogram in knowing the weight of your ball. And then you need to know the spacing of your silicon atoms to an equally high precision to start counting them.

Re:What's the problem? (1)

cavtroop (859432) | more than 6 years ago | (#24014839)

you didn't RTFA, did you?

"One proposal, pushed by an international team called the Avogadro Project, aims to define the kilogram in terms of a specific number of silicon atoms. Just how many? That's where the newly created silicon spheres come in."

they're creating these spheres so they can measure that. The article is pretty neat, actually.

Re:What's the problem? (1)

kalirion (728907) | more than 6 years ago | (#24014913)

Does this mean that we do not, in fact, know the atomic weight of Silicon to a precise enough degree?

Re:What's the problem? (2, Interesting)

nkh (750837) | more than 6 years ago | (#24014877)

Where I was studying a few years ago, I had a teacher who was working with a french laboratory to create a standard for the kilogram. It was supposed to work with a machine to record the pressure applied to it (some kind of scale as far as I understood) and a bunch of lasers to measure everything. It was the first and only time I've heard about someone trying to standardize the kilogram.

It *is* based on measurable quantity... (4, Funny)

Anne_Nonymous (313852) | more than 6 years ago | (#24015003)

A kilogram is defined as exactly 2.20462262 pounds of pure water at pressure of 100 kPa (1 bar) and a temperature of 273.15 K. :)

Re:It *is* based on measurable quantity... (1)

ericrost (1049312) | more than 6 years ago | (#24015193)

So how do you define a pound?

Re:It *is* based on measurable quantity... (1)

rugatero (1292060) | more than 6 years ago | (#24015223)

But a pound is defined relative to the Kilo, as agreed in 1958. (0.453 592 37)

Re:What's the problem? (1)

phobos13013 (813040) | more than 6 years ago | (#24015037)

Well, the problem comes from some changes in definition of SI Units. Most notably between relative changes in mass from the standard kilogram which introduces uncertainty to any measurement. Also, this change can tie Avogadro's constant to the kilogram as a result! Currently it is a measure of atoms/molecules in a gram of substance (with units of inverse mol), and as a result is not exact. By making it unitless as tying it to a count of the kilogram atoms the measure can now be exact!

manufacturing problems (5, Informative)

Moraelin (679338) | more than 6 years ago | (#24015117)

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.

Re:What's the problem? (2, Informative)

Reality Master 101 (179095) | more than 6 years ago | (#24015119)

I've never really understood the problem with creating a more stringent definition of the kilogram.

Others have pointed out that they are doing more or less what you advocate, but let me address the more general issue.

Remember that the definitions for the fundamental units are intended, above all, to be *practical*. In other words, the goal is to make the definition as easy as possible for a competent scientist/engineer anywhere in the world to reproduce in order to calibrate some instrument. All the fundamental units have been defined this way, except one: the kilogram.

There are numerous ways they could define a kilogram, but they all suffer either from the non-portability problem (e.g., using a unique artifact, which no one has access to), or the expensive, difficult device problem. Counting the number of atoms in a perfect sphere is not exactly a simple engineering problem. But it's the best anyone has come up with so far.

Re:What's the problem? (1)

Markspark (969445) | more than 6 years ago | (#24015173)

because the atomic mass unit U is defined from the thesis that 1 mole of Carbon atoms weighs in at 12 grams.

sphere (2, Interesting)

Elisanre (1108341) | more than 6 years ago | (#24014693)

Is there a reason for it to be a sphere? Easier to determin the weight?

Re:sphere (2, Informative)

marcovje (205102) | more than 6 years ago | (#24014961)


Crystal growth is often spherical. And very controlled crystal growth is a method to get a very uniform object without (many) defects.

Re:sphere (1)

marcovje (205102) | more than 6 years ago | (#24015189)

Hmm, it seems they polish it manually. Probably because it doesn't have edges then, which makes polishing it easier.

Is crystal growth really the reason why? (5, Interesting)

wisebabo (638845) | more than 6 years ago | (#24015201)

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:sphere (3, Informative)

NovaHorizon (1300173) | more than 6 years ago | (#24015207)

close. Easier to determine atom count with a sphere. something like..

number of atoms = (volume * density) / mass of silicon atom

With the volume of a perfect sphere simply being

Pi*r^3 (I think)

It's also much much easier to test for the perfection of a sphere over any other geometric shape. All you do is spin it with slight axis rotation while a laser is pointed at it, and measure the distance.

Cleanroom? (4, Insightful)

lobiusmoop (305328) | more than 6 years ago | (#24014705)

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

Re:Cleanroom? (4, Funny)

sveard (1076275) | more than 6 years ago | (#24014747)

Just wipe it off with some kleenex.

Was Intel behind this? (0)

Anonymous Coward | more than 6 years ago | (#24014723)

These spheres look an awful lot like the ones featured in the ray-traced version of quake wars [tgdaily.com] ...

Pong (5, Funny)

The Crooked Elf (1042996) | more than 6 years ago | (#24014735)

In other news... these same scientists are hosting the BEST GAME OF PONG EVER this weekend!

Covered before (1)

icegreentea (974342) | more than 6 years ago | (#24014741)

Covered this before on slashdot.

http://science.slashdot.org/article.pl?sid=07/06/15/0541230

That article was amount this (they were planning). This article is about them actually completing the task. Almost a dupe, not quite. Random stuff I remember from the last discussing. The sphere works be calculating the amount of silicon atoms that would weigh one kilogram (I'm guessing the kilogram as defined by the Paris Standard), and then using the crystalline structure of silicon to find the exact dimensions of a sphere containing that amount of atoms, and then they would go and mill the perfect sphere. By defining it as a precise number of silicon atoms, people can in theory completely recreate the kilogram if every standard was destroyed. As it stands now, if we lost the Paris standards, all the scales in the world would lose precision, and a kilogram here would not be a kilogram there.

Mass scales have to have something physical to be calibrated against, so even if they defined kilogram as so and so many natural constants (Plank mass?), there would still have to be some sort of stable physical thing to calibrate the scales with (hence this badass sphere).

Re:Covered before (0)

Anonymous Coward | more than 6 years ago | (#24014997)

not only "before", but ONE YEAR before.

this link is from 2007.

Metric... (5, Funny)

jo7hs2 (884069) | more than 6 years ago | (#24014753)

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.

Re:Metric... (3, Funny)

gardyloo (512791) | more than 6 years ago | (#24014919)

Perhaps it's due to the changing masses of ducks? I'm just sayin'...

Re:Metric... (1)

realisticradical (969181) | more than 6 years ago | (#24015019)

I was intrigued by your comment and wanted to see how the pound was defined so I went to wikipedia. http://en.wikipedia.org/wiki/Pound_(mass) [wikipedia.org] Apparently it's based on the kilogram.

More importantly though I got to the chart a little ways down the page comparing different types of the pound and my head exploded.

Re:Metric... (1)

odourpreventer (898853) | more than 6 years ago | (#24015181)

Apparently it's based on the kilogram.

I find this peculiar. I went to GVSU in Michigan for a short while (I'm from Sweden), and there the pound was used as a measure of force. My Swedish textbooks also had coefficients for converting between lb and N.

Re:Metric... (4, Interesting)

odourpreventer (898853) | more than 6 years ago | (#24015055)

It gets worse. US standards are based on metric standards. (For instance, the inch is defined as 25.4 mm.) You're basically using a French system!

Based on? (1)

biolysis (1303409) | more than 6 years ago | (#24015145)

Would you care to explain how a system that was in existence BEFORE the metric system was devised is "based on"it?

You and the post above yours seem to be confusing "is equivalent to" with "based on".

Re:Based on? (1)

maxume (22995) | more than 6 years ago | (#24015211)

"are now defined in terms of"

At the moment, when the standard kilogram changes, so does the pound. The relationship is one sided, not equivalent.

Re:Based on? (1)

a_real_bast... (1305351) | more than 6 years ago | (#24015245)

In the United States, the (avoirdupois) pound as a unit of mass has been officially defined in terms of the kilogram since the Mendenhall Order of 1893.

In 1958 the United States and countries of the Commonwealth of Nations agreed upon common definitions for the pound and the yard. The international avoirdupois pound was defined as exactly 453.59237 grams.


From the Wikipedia article [wikipedia.org] posted elsewhere in the comments by realisticradical.

Has to be said... (1)

naich (781425) | more than 6 years ago | (#24014763)

It sounds like a load of balls to me.

Double Dupe (2, Informative)

little1973 (467075) | more than 6 years ago | (#24014775)

Re:Double Dupe (4, Informative)

wvmarle (1070040) | more than 6 years ago | (#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.

wow (1, Funny)

Anonymous Coward | more than 6 years ago | (#24014819)

I guess silicone is the solution for everything that deforms. What? Oh, silicon...

Their next project is more difficult (1)

MiniMike (234881) | more than 6 years ago | (#24014825)

Next up for them is creating 10 perfect (but miniature) bowling pins. This is all part of a misguided effort to bowl a perfect 300 game. Have to applaud the effort though.

Seriously, isn't this just a stopgap effort to mitigate some of the problems with the current standard? It sounds like the Watt balance technique mentioned in TFA is a much better idea. Hopefully the techniques used in the sphere effort can also be used elsewhere.

You Think Your Job Sucks? (1)

Scumbumbo (521718) | more than 6 years ago | (#24014835)

It should be possible to count exactly the number of atoms in one of the roughly 9cm silicon spheres to define the unit.

That has got to be the most tedious, boring job ever!

When asked for her opinion.... (0)

Anonymous Coward | more than 6 years ago | (#24014837)

Pamela Andersen was not available for comment on the perfectly round silicon spheres.

Ah Ha! Take that! (5, Funny)

Anonymous Coward | more than 6 years ago | (#24014847)

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

Off topic, but ... (1)

OneSmartFellow (716217) | more than 6 years ago | (#24014883)

Personally - I'm trying to get everyone to convert to decimal time. under decimal time: 1 day = 10 hours 1 hour = 100 minutes 1 minute = 100 seconds That means a day would have 100,000 seconds, making each second equal to about 0.86 of the currently defined second. This would make my life much easier, although my wife might be dissapointed that I'd only be good for a little over 1 minute.

You know, roughly (5, Funny)

intx13 (808988) | more than 6 years ago | (#24014903)

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."

1 KG == 1 of God's nuts (0)

Anonymous Coward | more than 6 years ago | (#24014927)

Done.

Re:1 KG == 1 of God's nuts (1)

TheVelvetFlamebait (986083) | more than 6 years ago | (#24015209)

Wouldn't that create a lot of divisions by zero?

just add water (5, Interesting)

krystar (608153) | more than 6 years ago | (#24014949)

why not just define a kg as 1 Liter of pure H2O at 4deg C?....it is that way anyway.

pi (3, Funny)

oni (41625) | more than 6 years ago | (#24014965)

Does this also pin down the value of pi? I mean, they know exactly how many silicon atoms are on the surface of the sphere, and they know exactly how many atoms there are from the center to the surface.

hmm.

Re:pi (1)

Deadstick (535032) | more than 6 years ago | (#24015107)

Does this also pin down the value of pi?

Been done.

rj

If its the perfect sphere... (1)

Tekninja_Hawk (961855) | more than 6 years ago | (#24014991)

It should be able to play the perfect Skiball game.

I beg to differ (3, Funny)

Rinisari (521266) | more than 6 years ago | (#24015015)

The roundescht object in the world isch your mother, Trebek.

Gravity Probe B has more Perfect Spheres (5, Interesting)

wooferhound (546132) | more than 6 years ago | (#24015139)

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"

no no no read this (0)

Anonymous Coward | more than 6 years ago | (#24015151)

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

Changing Mass? (1)

skirmish666 (1287122) | more than 6 years ago | (#24015153)

"its mass is changing relative to copies held elsewhere"
I've heard this before but no-ones been able to explain it to me. What exactly is happening to the mass of the platinum spheres and why?

Re:Changing Mass? (3, Interesting)

Shados (741919) | more than 6 years ago | (#24015221)

Its shrinking. Losing incredibly small pieces over long periods of times. No object can realistically stay -exactly- the same forever.

I can't believe no one has posted this... (3, Interesting)

carlcmc (322350) | more than 6 years ago | (#24015159)

They should have visited this guy's website

http://www.kyokyo-u.ac.jp/youkyou/4/english4.htm?

making spherical mud balls. I've had this bookmarked in del.icio.us for a long time

Not so perfect.... (0)

Anonymous Coward | more than 6 years ago | (#24015171)

"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,"

Common only 5m accuracy??? Even GPS is better than that....

But... (0)

Anonymous Coward | more than 6 years ago | (#24015191)

Still not as round as Karl Pilkington's head...

Now the measurement relies on a retiree (2, Interesting)

Phurge (1112105) | more than 6 years ago | (#24015199)

from TFA "To shape the spheres, the Australian Center for Precision Optics pulled optical engineer Achim Leistner out of retirement. Leistner, who has been creating precision spheres for decades, considers these final two to be his masterpieces"

Great. What happens when this guy kicks the bucket?
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