But new technologies could change the official way we measure a second, and could be key to new communications technologies. The optical lattice clock — using lasers and strontium atoms — is accurate to within one second every million years, and is more stable than current atomic clocks. Optical clocks work similarly to atomic clocks, but measure the oscillations of ions or atoms which vibrate at about , times the frequency of microwave frequencies.
Such clocks could provide the basis for a new official definition of the second, scientists argue. In the future, such clocks might help navigate human beings towards other planets — and even beyond, says Jun Ye of the University of Colorado Boulder. The US consumer price index rose at an annual rate of 6. A gust of wind caused fall leaves to twirl and dance on a tennis court in Boulder, Colorado, on Wednesday, November According to the National Weather Service, wind gusts reached a peak of around 35 miles per hour in the Boulder area.
This video was posted to Twitter by boulderdaily. Credit: Boulder Daily via Storyful. Belarusian opposition leader Svetlana Tikhanovskaya on Thursday said strongman Alexander Lukashenko would not follow through on threats to cut off gas supplies to Europe over an escalating conflict with the EU.
An Olympic gold medallist has said she was pepper-sprayed in a racist attack while waiting for an Uber with a group of friends. Sunisa 'Suni' Lee said she experienced the attack recently, as she opened up about the ordeal in an interview with PopSugar. Lee became the first Asian-American woman to win Olympic gold in the women's gymnastics all-around at the Tokyo Games.
In a town swept up in the migrant crisis on the Poland-Belarus border, residents said they were worried by the growing tensions but voiced support for the Polish government's tough stance. The findings come after university students have returned to campuses across the UK for more in-person lessons and social activities. A British pop star was also unmasked. Broyles said he shot the video on October 26, near the Grand Prismatic Spring. Credit: Shane Broyles via Storyful. A pharmaceutical company could sue the Government over the Health Secretary's claim that the firm's vaccine "would not get approval", its chief financial officer has said.
Michael Fawcett and his party planning company will also no longer be providing services to Clarence House a spokesperson said. Register or Log In.
The Magazine Shop. Login Register Stay Curious Subscribe. The Sciences. Newsletter Sign up for our email newsletter for the latest science news. Sign Up. Already a subscriber? Want more? More From Discover. The leap second is expensive for computing and financial institutions, which must account for it in calculations and modifications, so many people think we should simply let leap seconds accumulate until we have a full leap minute , then make the adjustment.
Jefferts, however, is in agreement with most astronomers and thinks we should keep the leap second. I'm a sailor, and many years ago I taught celestial navigation, and so I sort of have this very personal linkage idea that, dammit, the sun should be overhead on the 21st of March or the 20th of March [the spring equinox] at noon at Greenwich We should not be accumulating leap seconds so that that is no longer true.
Leap seconds are far from the only ongoing uncertainty about time. The current definition of a second, 9,,, periods of a maser that will cause cesium to transition, isn't perfect. For one thing, the duration of a second, as currently defined, is slightly different at altitude compared to sea level due to general relativity, so corrections need to be made.
It could be more accurate, and as a matter of fact, we have clocks that are more accurate. These optical clocks , as they are called, work similarly to cesium fountain clocks. However, instead of levitating a ball atoms, they simply trap those atoms in place in a chamber with a system of lasers and then use one specific laser to cause them to transition. The difference is in the frequency. A laser in the visible spectrum has a frequency that is around ten thousand times higher than the 9,,, Hz maser.
A definition for the second based on an optical clock would therefore be counted as some 90 trillion periods of radiation, sometimes called "ticks," rather than 9 billion, as it is now. And then if you walk to the hall over there, those guys will be like no it's aluminum ions. Unless of course you go to the room next door, at which point it's mercury ions, I'll tell you it's mercury ions! Additionally, lawmakers, who Jefferts says often have trouble grasping the definition of the second in the first place, are unlikely to change the standard unless they have a practical reason.
If there is a financial incentive, or a need to make computers more accurate, for example, the official definition of a second could be changed to an optical clock measurement. But whether that will happen in our lifetimes is unknown. Until then, like Jefferts, you might just want to memorize the number 9,,,, lest you lose track of the time. Type keyword s to search.
Today's Top Stories. If only the real world were so simple. America's Top Time Lab. The cylinder at the top contains the cloud of cesium atoms that are elevated using laser energy, and the optics table it is mounted on uses a suite of instruments to redirect and change the properties of the lasers.
Jay Bennett. This content is imported from YouTube. You may be able to find the same content in another format, or you may be able to find more information, at their web site. A note from Steve Jefferts in the F1 lab. A small fountain clock of rubidium. The rubidium, like the cesium in the larger F1, is contained in a glass ampoule that is inside the copper tube you can see on the side of the clock. To release the atoms, horologists simply crush the tube with a pair of pliers, and then adjust the temperature to control how many of the atoms become gaseous.
A ytterbium optical clock at NIST.
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