Latest news with #NIST-F1
Yahoo
04-05-2025
- Science
- Yahoo
US scientists debut atomic clock that stays true for 100 million years straight
Marvel's Time Variance Authority (TVA) would probably call dibs on this atomic clock if they could! The NIST-F4 atomic clock, recently unveiled by the National Institute of Standards and Technology in Boulder, Colorado, is one of the most accurate timekeeping devices ever built on Earth. This clock is so precise that if it had started ticking during the age of the dinosaurs, it would still be accurate today to within a single second. This month, NIST scientists officially submitted it to the International Bureau of Weights and Measures (BIPM) for certification as a 'primary frequency standard,' a title reserved for the most elite atomic clocks on the planet. Only around ten countries operate such clocks — now the U.S. is back in that top tier. Unlike regular clocks, atomic clocks like NIST-F4 keep time using the natural vibrations of atoms — in this case, cesium atoms. Inside the clock, thousands of these atoms are cooled to near absolute zero using lasers and then tossed upward in a fountain-like motion. As they rise and fall, they pass through microwave radiation tuned to a frequency that makes the atoms shift their energy state — a transition that defines the "tick" of the clock. That tick happens precisely 9,192,631,770 times per second, and counting those ticks is how the clock defines the official second. "Fountain clocks are supposed to be very boring," said Greg Hoth, a physicist on the NIST team. In this case, boring means reliable, and that's exactly what global systems depend on. Time isn't just about watches and alarms — it powers everything from GPS to stock market trades to data centers. 'Time signals are used literally billions of times each day for everything from setting clocks and watches to ensuring the accurate time stamping of hundreds of billions of dollars of electronic financial transactions,' said Liz Donley, who leads NIST's Time and Frequency Division. NIST-F4 helps steer the official U.S. time scale, known as UTC(NIST), and contributes to the global timekeeping standard, Coordinated Universal Time (UTC). Its ultra-precise data helps ensure systems worldwide stay synchronized down to the microsecond. NIST-F4 didn't happen overnight. It evolved from NIST-F1, the agency's first fountain clock built in the late 1990s. After a move in 2016 disrupted F1's performance, NIST scientists decided to rebuild the heart of the clock — the microwave cavity — from scratch. They spent years refining every part, from magnetic coils to optical systems, achieving tolerances as fine as one-fifth the width of a human hair. "Evaluating a fountain clock... is a slow process because we have to be very conservative,' said physicist Vladislav Gerginov. NIST has already submitted NIST-F4's data to the BIPM for formal certification. Meanwhile, it runs alongside NIST-F3 to ensure that at least one fountain clock is operating at all times. 'The success of NIST-F4 has renewed NIST's global leadership in primary frequency standards,' Donley said. And until optical clocks eventually redefine the second, cesium-based fountains like this one will keep global time ticking perfectly.
Yahoo
29-04-2025
- Science
- Yahoo
New Boulder atomic clock submitted to track world's time
DENVER (KDVR) — It is said that time is relative and passes differently depending on an observer's relative motion and gravitational potential. Although some would argue time is a construct, it does play a big part for all living things, and one group in particular, humans, has created an entire system based on time. Colorado Avalanche vs. Dallas Stars Game 6: TV channel, time, what to know With such a complex principle being experienced in different capacities by people all over the world, how can time really be measured? For people all over the globe, one area where time is monitored is by an atomic clock housed in the National Institute of Standards and Technology lab in Boulder. According to scientists at NIST in Boulder, their newest atomic clock, the NIST-F4, will help track time more precisely and help put global time on a more accurate frequency. Scientists believe in the ability of the F4 so much that they have submitted it to the International Bureau of Weights and Measures to be used as a primary frequency standard that would oversee the world's time. The F4 is based on the 'fountain' design, which has become the golden standard for timekeeping since 1967, by measuring the unchanging frequency in the heart of cesium atoms. NIST said that if the F4 atomic clock had started ticking 100 million years ago, when dinosaurs were abundant on Earth, it would be off by less than a second today. The F4 joins a group of atomic clocks operated in only 10 other countries around the world and will help make the foundation of global time more stable and secure by helping distribute time via the radio and internet, which are critical for a handful of functions, including: Telecommunications Transportation systems Financial trading platforms Data center operations 'NIST-F4 has improved time signals that are used literally billions of times each day for everything from setting clocks and watches to ensuring the accurate time stamping of hundreds of billions of dollars of electronic financial transactions,' said Liz Donley, chief of the Time and Frequency Division at NIST. The F4 will track time scales in the region and submit them to the other global clocks, which will be used to synchronize time in their areas. Speaking of time, the F4 is the byproduct of a process that began in the late 1990s, when the NIST-F1 was created. To function with such precision, the F4 will cool a cloud of thousands of cesium atoms to near absolute zero with lasers. A pair of lasers then tosses the atoms gently upward, before their own weight causes them to fall again. During that process, the atoms will pass through a small chamber full of microwave radiation twice. On the way up, the microwave will put the atoms into a quantum state that cycles at a frequency known as the cesium resonant frequency, which is an unchanging constant. Nearly a second later, the atoms will fall back down, and a second interaction determines how closely the microwaves' frequency aligns with the cesium resonant frequency of the atoms. The measurement is then taken to tune the microwave frequency toward the atomic resonance frequency, which will be counted by a detector for 9,192,631,770 wave cycles, a number that defines the official international second. What is severe weather season in Colorado? NIST said that the F4's frequency measurements are accurate to within 2.2 parts in 10 to the 16th (10 million billion), which is comparable to the best fountain clocks around the world. 'The success of NIST-F4 has renewed NIST's global leadership in primary frequency standards,' said Donley. '(Scientists)Vladi and Greg used ingenuity and skill to restore the reliable, world-class operation of NIST's atomic fountains.' A team at the International Bureau of Weights and Measures is testing the F4's data before it determines if it will be used as a clock for the primary frequency standard. Copyright 2025 Nexstar Media, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
