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US Objects To the Kilogram
Velcroman1 writes "For 130 years, the kilogram has weighed precisely one kilogram. Hasn't it? The US government isn't so sure. The precise weight of the kilogram is based on a platinum-iridium cylinder manufactured 130 years ago; it's kept in a vault in France at the International Bureau of Weights and Measures. Forty of the units were manufactured at the time, to standardize the measure of weight. But due to material degradation and the effects of quantum physics, the weight of those blocks has changed over time. That's right, the kilogram no longer weighs 1 kilogram, according to the National Institute of Standards and Technology. And it's time to move to a different standard anyway. A proposed revision would remove the final connection to that physical bit of matter, said Ambler Thompson, a NIST scientist involved in the international effort. 'We get rid of the last artifact.'"
Last I heard, nobody had come up with a way to define mass without referring to an artifact. It seems easy but they all turn out to be circular.
Death to KILLograms!
Ounces and pounds were way a head of the time and are becoming even more useful with the advent of computer systems and the common use of base16.
16 ounces in a Pound is not just coincidence.
F=15 ounces
10 = a pound
We can all agree, I am sure, it's easier to look at 89 and go, 8 pounds 9 ounces. With metric I have to keep moving the decimal place around and remember how many 0s there were in huge words like kilogram, milligram, centigram.
Because this prototypical kilogram is what the definition of the pound is currently based on.
It clearly states this is an international effort, and the objection is not the the unit 'kilogram' but rather to using a decaying (however slowly) object as the reference mass.
seriously, this is pretty old. physicists working in metrology have been working to redefine the kilogram for at least the last few decades
"For I am a Bear of Very Little Brain, and Long Words Bother Me"
We have American pints and British pints; the imperial tone, the short ton, and the tonne; why not have an American kilogram and traditional kilogram as well? That should really simplify things for NASA/EUA coordination.
Funnily enough I never ever think of a kilogram as the weight of some standard weight in a vault somewhere. The only way I ever think about the kilogram is the weight of one liter of water. Also comes in handy when I'm calculating how much liquids I can afford to buy when shopping groceries, given that I often go to the store on foot for the exercise and have to make sure I can manage the haul back.
So, um, does this all really matter? In practice, that is.
.: Max Romantschuk
It's the US of A -- we don't use the kilogram anyway. Change it as you like.
That being said, keep your filthy hands off my hogshead.
Blog,Twitter
"There is one thing of which one can say neither that it is one metre long, nor that it is not one metre long, and that is the standard metre in Paris." - Wittgenstein, Philosophical Investigations
We're going to let the kilogram "float" and put it on the commodities market. It should triple the value of the gram
For justice, we must go to Don Corleone
I'm not even sure we even use Imperial units anymore...
From reading the news, I believe our units are:
- Hairs
- Stories
- Football Fields
- Libraries of Congress
Newton is a weight. The summary (and the Fox article) are incorrect, while the NIST article correctly refers to the reference mass.
MJC
and misses the point. The variability of the kilogram standard is a scientific and engineering concern, not a political one.
Wikipedia discusses the issue: http://en.wikipedia.org/wiki/Kilogram#Proposed_future_definitions
In a nutshell - in order to create 1 kilogram physical standard masses, you have to first know what a kilogram IS. The physical standards referred to in the article do not appear to have retained constant mass over time. You can't define a constant based on something that is variable, so the current masses are (as I understand it) acknowledged to be an inadequate basis for the definition of the unit. The problem arises when you try to pick something to define it with that is both stable (i.e. a fundamental property of the natural laws of the universe) and practical (can actually create one to use as a practical mass standard against which you can prepare working standards.)
From articles that have popped up about this over the years, my guess is they will have to pick something as a basis and then work on various practical techniques to get as close to that ideal as possible - the question is what specifically to pick. N Carbon atoms? N Si atoms? What are the pros and cons when trying to physically create something that represents those numbers? How stable will a standard created according to a chosen standard be over time? (I.e., how often to we have to make new master standards? It's an important question - obviously the existing masses were not chosen with the expectation that their mass would vary with time, so how do we know to trust a given solution?)
So it's not the US objecting to the kilogram as a unit, but rather concern over the methods used to DEFINE the unit. That's something quite rational, not specific to the USA, and of scientific interest. Editors, how about changing the title to "US to Propose New Method of Defining a Standard Kilogram" instead?
"I object to doing things that computers can do." -- Olin Shivers, lispers.org