babych Posted August 26, 2013 Share Posted August 26, 2013 This is very cool. Link (there's a good video): http://www.huffingtonpost.com/2013/08/23/worlds-roundest-object-perfect-sphere_n_3804690.html?utm_hp_ref=science&ir=Canada Article: In a world where everything strives to be the best and the biggest, scientists behindThe Avogadro Project in Australia have sought a surprising superlative: the world's roundest object. And they aren't just doing it for bragging rights. Instead, the remarkable sphere may provide a solution to what's known as the "kilogram problem." Unlike other scientific units, which can theoretically be measured anywhere in the world based on natural properties, the kilogram is still based on a physical object: a cylinder of platinum and iridium that dates back to 1889. So while the "meter" is defined as the distance light travels in a tiny fraction of a second, and the "second" can be counted by the precise decay of an atom, the kilogram is no more (and no less) than a physical mass that sits in a secured vault at the Bureau International des Poids et Mesures in Paris. For reasons no one understands -- and despite precautionary measures -- the cylinder's mass keeps changing. In other words, the kilogram, as defined by the cylinder (and compared to 40 exact replicas of the cylinder kept in other countries), doesn't weigh the same as it used to. To solve that problem, researchers at the Australian Centre for Precision Optics, which is home to The Avogadro Project, are crafting nearly perfect spheres made of a highly pure and very stable form of silicon. By calculating the sphere's volume and weight, scientists should be able to determine the exact number of silicon atoms in the object itself, thereby providing an unchanging definition for the mass of a kilogram. Per Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO), scientists settled on a sphere as the standard shape because it "has no edges that might get damaged," and "only one dimension [its diameter] has to be measured in order to calculate its volume." As for how the world's roundest objects were made, New Scientist reports two spinning rotors ground them for several months. Afterward, computer-guided lasers measured each for slight derivations that were corrected individually. "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," CSIRO master optician Achim Leistner said of the end result. A second, competing method to determine a standard measurement for the kilogram is the "watt balance" -- a system tied to Earth's gravitational pull on a kilogram and the force needed to counteract it. This strategy has also earned quite a following. Despite these advances, the standard kilogram remains a cylinder that's more than 120 years old -- at least for now. And until the world's roundest object proves its mettle, well, we'll just have to roll with it. I loves me the science. Link to comment Share on other sites More sharing options...
Amish Rake Fighter Posted August 26, 2013 Share Posted August 26, 2013 I always thought that the roundest thing on earth was Karl Pilkington's head. Link to comment Share on other sites More sharing options...
timberz21 Posted August 26, 2013 Share Posted August 26, 2013 GMMG got outgm again. Why didn't he think of that. Link to comment Share on other sites More sharing options...
elvis15 Posted August 26, 2013 Share Posted August 26, 2013 I always thought that the roundest thing on earth was Karl Pilkington's head. Link to comment Share on other sites More sharing options...
Drive-By Body Pierce Posted August 26, 2013 Share Posted August 26, 2013 Another reference for a kilogram is a cubic meter of pure water, though the whole evaporation thing doesn't exactly lend itself to the stability aspect. Link to comment Share on other sites More sharing options...
Amish Rake Fighter Posted August 26, 2013 Share Posted August 26, 2013 Nope, he needs his 'Dougie' wig to make it extra round. Link to comment Share on other sites More sharing options...
Dittohead Posted August 26, 2013 Share Posted August 26, 2013 Play Now! Link to comment Share on other sites More sharing options...
hudson bay rules Posted August 26, 2013 Share Posted August 26, 2013 Another reference for a kilogram is a cubic meter of pure water, though the whole evaporation thing doesn't exactly lend itself to the stability aspect. Link to comment Share on other sites More sharing options...
Columbo Posted August 26, 2013 Share Posted August 26, 2013 Another reference for a kilogram is a cubic meter of pure water, though the whole evaporation thing doesn't exactly lend itself to the stability aspect. Link to comment Share on other sites More sharing options...
Columbo Posted August 26, 2013 Share Posted August 26, 2013 I once took a dump that I'm pretty sure was exactly 1kg, do you think they'll consider that as a potential new definition? Link to comment Share on other sites More sharing options...
ilduce39 Posted August 26, 2013 Share Posted August 26, 2013 I once took a dump that I'm pretty sure was exactly 1kg, do you think they'll consider that as a potential new definition? Link to comment Share on other sites More sharing options...
JoeyJoeJoeJr. Shabadoo Posted August 26, 2013 Share Posted August 26, 2013 Wouldn't it have been easier to make a ball that weighs a gram and then multiply by a thousand? Link to comment Share on other sites More sharing options...
elvis15 Posted August 26, 2013 Share Posted August 26, 2013 Jeezus that's round. I haven't seen that show yet, is it any good ? Link to comment Share on other sites More sharing options...
GLASSJAW Posted August 26, 2013 Share Posted August 26, 2013 I once took a dump that I'm pretty sure was exactly 1kg, do you think they'll consider that as a potential new definition? Link to comment Share on other sites More sharing options...
YaK Posted August 26, 2013 Share Posted August 26, 2013 actually, one litre at 4C Link to comment Share on other sites More sharing options...
hudson bay rules Posted August 27, 2013 Share Posted August 27, 2013 Wouldn't it have been easier to make a ball that weighs a gram and then multiply by a thousand? Link to comment Share on other sites More sharing options...
hudson bay rules Posted August 27, 2013 Share Posted August 27, 2013 Not bad, some really funny parts but a lot of looking at old people and feeling like you should go visit your grandparents/parents. But interesting about the litre of water at 4C as another attempt at the measurement. Weird that it hasn't actually been anything static like the other measurements in the OP. Link to comment Share on other sites More sharing options...
Columbo Posted August 27, 2013 Share Posted August 27, 2013 I'm curious. If the earth's core isn't exactly 100% stable then gravity pulling object down towards the core should fluctuate and therefore objects don't always weigh the same. A perfect sphere would have it's mass at the centre rather than let's say, a brick where the mass is spread out so gravity always pulls on the centre rather than the sides. Link to comment Share on other sites More sharing options...
Columbo Posted August 27, 2013 Share Posted August 27, 2013 Wouldn't it have been easier to make a ball that weighs a gram and then multiply by a thousand? Link to comment Share on other sites More sharing options...
hudson bay rules Posted August 27, 2013 Share Posted August 27, 2013 Mass isn't the same as weight Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.