VIDEO: The definition of a kilogram has officially changed

50-plus countries voted to a ground-breaking overhaul to the international system of measurements

A replica of the International Meter Prototype is pictured at the International Bureau of Weights and Measures, in Sevres, near Paris. (AP Photo/Christophe Ena)

A replica of the International Meter Prototype is pictured at the International Bureau of Weights and Measures, in Sevres, near Paris. (AP Photo/Christophe Ena)

In a historic vote, nations on Friday unanimously approved a ground-breaking overhaul to the international system of measurements that underpins global trade and other vital human endeavours, uniting together behind new scientific definitions for the kilogram and other units in a way that they have failed to do on so many other issues.

Scientists, for whom the update represents decades of work, clapped, cheered and even wept as the 50-plus nations gathered in Versailles, west of Paris, one by one said “yes” or “oui” to the change, hailed as a revolution for how humanity measures and quantifies its world.

The redefinition of the kilogram, the globally approved unit of mass, was the mostly hotly anticipated change. For more than a century, the kilogram has been defined as the mass of a cylinder of platinum-iridium alloy kept in a high-security vault in France. That artefact, nicknamed “Le Grand K,” has been the world’s sole true kilogram since 1889.

But now, with the vote, the kilogram and all of the other main measurement units will be defined using numerical values that fit handily onto a wallet card. Those numbers were read to the national delegates before they voted.

Scientists at the meeting were giddy with excitement: some even sported tattoos on their forearms that celebrated the science.

Nobel prize winner William Phillips called the update “the greatest revolution in measurement since the French revolution,” which ushered in the metric system of meters and kilograms.

Jon Pratt of the U.S. National Institute of Standards and Technology said the vote left him “a basket case” and “extremely emotional.”

“Those units, those constants chosen now, include everything we know, everything we have always known and provide that springboard for us to go pursue those things that we don’t know,” he said. “That was just leaving me in a puddle of tears.”

The Grand K and its six official copies, kept together in the same safe on the edge of Paris and collectively known as the “heir and the spares,” will be retired but not forgotten. Scientists want to keep studying them to see whether their masses decay over time.

The change will have no discernable impact for most people. Bathroom scales won’t suddenly get kinder and kilos and grams won’t change in supermarkets.

But the new formula-based definition of the kilogram will have multiple advantages over the precision-crafted metal lump that set the standard from the 19th century to the 21st, through periods of stunning human achievement and stunning follies, including two world wars.

Unlike a physical object, the new formula for the kilo, now also known as “the electric kilo,” cannot pick up particles of dust, decay with time or be dropped and damaged.

It is expected to be more accurate when measuring very, very small or very, very large masses and help usher in new innovations in science, industry, climate study and other fields.

With time, as the science behind the new definition becomes more accessible and affordable, it should also mean that countries won’t have to send their own kilograms back to France to be checked occasionally against Le Grand K, as they have done until now, to see whether their mass was still accurate.

John Leicester, The Associated Press

Like us on Facebook and follow us on Twitter

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

A health care worker prepares to test a Coastal GasLink field worker for COVID-19. (Coastal GasLink photo)
Coastal GasLink begins COVID screening of pipeline workers

Construction is once again ramping up following Northern Health approval of COVID management plan

A housing location for workers on the new Mills Memorial Hospital construction project has been approved by city council. (File photo)
Camp spot proposed for hospital construction workers

As many as 350 outside workers may be needed

Terrace city council are reaching out to the B.C. Office of the Ombudsperson regarding councillor Jessica McCallum-Miller’s resignation on Feb. 22, 2021. (Black Press Media File Photo)
City of Terrace seeking ombudsperson investigation into allegations of systemic racism

Councillor Jessica McCallum-Miller resigned Feb. 22, citing racism

A large provincial grant will make cycling and walking safer in Terrace. (File photo)
Large grant to make walking, cycling safer in Terrace

Pathway will connect old Skeena Bridge to the downtown

Pig races at the 145th annual Chilliwack Fair on Aug. 12, 2017. Monday, March 1, 2021 is Pig Day. (Jenna Hauck/ Chilliwack Progress file)
Unofficial holidays: Here’s what people are celebrating for the week of Feb. 28 to March 6

Pig Day, Canadian Bacon Day and Grammar Day are all coming up this week

Staff from the Marine Mammal Rescue Centre, passersby, RCMP and Nanaimo Fire Rescue carried a sick 300-kilogram steller sea lion up the steep bluff at Invermere Beach in north Nanaimo in an attempt to save the animal’s life Thursday. (Photo courtesy Marine Mammal Rescue Centre)
300-kilogram sea lion muscled up from B.C. beach in rescue attempt

Animal dies despite efforts of Nanaimo marine mammal rescue team, emergency personnel and bystanders

Kara Sorensen, diagnosed with lung cancer in July, says it’s important for people to view her as healthy and vibrant, rather than sick. (Photo courtesy of Karen Sorensen)
B.C. woman must seek treatment overseas for inoperable lung cancer

Fundraising page launched on Karen Sorensen’s behalf, with a goal of $250,000

Gina Adams as she works on her latest piece titled ‘Undying Love’. (Submitted photo)
‘Toothless’ the kitty inspires B.C. wood carver to break out the chainsaw

Inspired by plight of a toothless cat, Gina Adams offers proceeds from her artwork to help animals

B.C. Finance Minister Selina Robinson presents bill to delay B.C.’s budget as late as April 30, and allow further spending before that, B.C. legislature, Dec. 8, 2020. (Hansard TV)
How big is B.C.’s COVID-19 deficit? We’ll find out April 20

More borrowing expected as pandemic enters second year

The first of 11 Dash 8 Q400 aircraft's have arrived in Abbotsford. Conair Group Inc. will soon transform them into firefighting airtankers. (Submitted)
Abbotsford’s Conair begins airtanker transformation

Aerial firefighting company creating Q400AT airtanker in advance of local forest fire season

The Canada Revenue Agency says there were 32 tax fraud convictions across the country between April 2019 and March 2020. (Pixabay)
Vancouver man sentenced to 29 months, fined $645K for tax evasion, forgery

Michael Sholz reportedly forged documents to support ineligible tax credits linked to homeownership

Then-Liberal leader Andrew Wilkinson looks on as MLA Shirley Bond answers questions during a press conference at Legislature in Victoria. (Chad Hipolito / THE CANADIAN PRESS)
B.C. Liberal party to choose next leader in February 2022

Candidates have until Nov. 30 to declare whether they are running

After nearly 10 months of investigations, Mounties have made an arrest in the tripping of an elderly woman in Burnaby this past April. (RCMP handout)
VIDEO: Mounties charge suspect for tripping elderly woman near Metrotown in April

32-year-old Hayun Song is accused of causing bodily harm to an 84-year-old using her walker

Most Read