The 118-year-old cylinder that is the international prototype for the metric mass, kept tightly under lock and key outside Paris, is mysteriously losing weight — if ever so slightly. Physicist Richard Davis of the International Bureau of Weights and Measures in Sevres, southwest of Paris, says the reference kilo appears to have lost 50 micrograms compared with the average of dozens of copies.
"The mystery is that they were all made of the same material, and many were made at the same time and kept under the same conditions, and yet the masses among them are slowly drifting apart," he said. "We don't really have a good hypothesis for it."
The kilogram's uncertainty could affect even countries that don't use the metric system — it is the ultimate weight standard for the U.S. customary system, where it equals 2.2 pounds. For scientists, the inconstant metric constant is a nuisance, threatening calculation of things like electricity generation.
"They depend on a mass measurement and it's inconvenient for them to have a definition of the kilogram which is based on some artifact," said Davis, who is American.
But don't expect the slimmed-down kilo to have any effect, other than possibly envy, on wary waistline-watchers: 50 micrograms is roughly equivalent to the weight of a fingerprint.
"For the lay person, it won't mean anything," said Davis. "The kilogram will stay the kilogram, and the weights you have in a weight set will all still be correct."
Of all the world's kilograms, only the one in Sevres really counts. It is kept in a triple-locked safe at a chateau and rarely sees the light of day — mostly for comparison with other cylinders shipped in periodically from around the world.
"It's not clear whether the original has become lighter, or the national prototypes have become heavier," said Michael Borys, a senior researcher with Germany's national measures institute in Braunschweig. "But by definition, only the original represents exactly a kilogram."
The kilogram's fluctuation shows how technological progress is leaving science's most basic measurements in its dust. The cylinder was high-tech for its day in 1889 when cast from a platinum and iridium alloy, measuring 1.54 inches in diameter and height.
At a November meeting of scientists in Paris, an advisory panel on measurements will present possible steps toward basing the kilogram and other measures — like Kelvin for temperature, and the mole for amount — on more precise calculations. Ultimately, policy makers from around the world would have to agree to any change.
Many measurements have undergone makeovers over the years. The meter was once defined as roughly the distance between scratches on a bar, a far cry from today's high-tech standard involving the distance that light travels in a vacuum.
One of the leading alternatives for a 21st-century kilogram is a sphere made out of a Silicon-28 isotope crystal, which would involve a single type of atom and have a fixed mass.
"We could obviously use a better definition," Davis said.
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FYI, i love news...this news of the shrinking ancient something really intrigued me...and the resignation of Shinzo Abe, (Prime minister or Japan, here's another clip)
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TOKYO - Japanese Prime Minister Shinzo Abe was hospitalized for stress and exhaustion Thursday, a day after announcing his resignation, as his party scrambled to find a replacement amid growing calls for a general election.
Abe, 52, was to remain hospitalized for at least three or four days, his doctors said, leaving the care of his scandal-scarred government with his top deputy, Chief Cabinet Secretary Kaoru Yosano.
"He is suffering from extreme exhaustion," said Dr. Toshifumi Hibi at Keio University Hospital. "He has lost weight. Symptoms include abdominal pain, digestion problems and lack of appetite."
Abe, 52, surprised members of his party and even his own Cabinet on Wednesday by deciding to resign only days after he pledged to stake his government on the success of legislation to extend a naval mission providing fuel for coalition warships in the Indian Ocean.
The nationalist Abe, whose government was severely damaged by a string of scandals and his party's loss of control of the upper house of parliament in July elections, said someone more politically viable should shepherd the Afghan measure that the opposition is trying to scuttle.
Chief Cabinet Secretary Kaoru Yosano had said medical problems contributed to Abe's decision. Abe had been receiving regular checkups from his personal doctor since returning from a regional summit in Australia earlier this week, Yosano said.
Abe's resignation, meanwhile, left the troubled ruling Liberal Democratic Party scrambling for a replacement amid growing calls for a general election to give voters a role in choosing the new government.
Kyodo News agency reported the ruling Liberal Democratic Party would hold its election for party president on Sept. 23. The winner is assured of being elected prime minister by parliament because of the LDP majority in the lower house. The LDP refused to immediately confirm the report.
The front-runner to replace Abe, former foreign minister and fellow conservative Taro Aso, was expected to announce his candidacy later Thursday.
Abe's popular predecessor, Junichiro Koizumi, reportedly refused supporters' plea to join the race. But Finance Minister Fukushiro Nukaga, who served as defense minister under Koizumi, said he wanted to run.
Calls for a snap election for the powerful lower house of parliament, which chooses the prime minister, gathered steam Thursday amid the confusion. The opposition took control of the upper house of parliament in elections on July 29, capitalizing on the unpopularity of Abe's scandal-scarred government.
"With the LDP government thrown into this much confusion, the voters should be asked in the proper fashion who their choice for leader is in a general election," the national Asahi newspaper said in an editorial. "That is the only way to bring back politics based on the people's trust."
Abe made no mention of his medical problems when announcing his resignation. But his vague reasons for leaving — that he felt a new leader was needed to unite the ruling and opposition parties — and the awkward timing fueled speculation he was forced out by the LDP leadership and suffered from health troubles.
Abe, whose support ratings in opinion polls had sagged to about 30 percent, has not yet announced a date for his departure.
When he steps down, Abe will leave behind a government known for scandals and gaffes. He is also leaving amid a political brawl over the country's aid to U.S.-led forces in Afghanistan
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