text: (CNN) -- If you follow scientific developments as if they were football games, this would be a good time to cheer "Tick-tick-tick-tick! Tick-tick-tick-tick! Go, clock, go!" 
   
   The reason for such enthusiasm? Researchers have released a study in the journal Science describing what they believe is the world's most precise clock. 
   
   You'd never need this level of precision for getting to work on time, but the clock could be used for scientific exploration and technological advancements in areas such as navigation systems, said study co-author Andrew Ludlow, researcher at the National Institute of Standards and Technology in Boulder, Colorado. 
   
   The rate of ticking of this timepiece -- known informally (and awkwardly) as the ytterbium optical lattice clock -- does not change by more than one part in 10^18, Ludlow said. In other words, if there is any variation in how a second is measured, it would be in about the 18th decimal place. 
   
   "The ytterbium optical lattice clock has demonstrated a groundbreaking, new level of clock stability," he said. "One could say that this is like measuring time over a hundred years to a precision of several nanoseconds." 
   
   In order to understand what's so special about this table-sized clock, it helps to have a little background: 
   
   How clocks work 
   
   Inside a clock is a mechanism that changes in some regular way, called an oscillator. Imagine, for example, a grandfather clock, whose pendulum swings back and forth denoting time. In a wrist watch there is often a crystal with an electrically oscillating signal. 
   
   A particular number of "back and forths" corresponds to one second. 
   
   An atomic clock makes use of an electromagnetic signal -- in other words, light emitted at an exact, known frequency. At the core of the system, there is an atom. The light is used to excite an electron in the atom. 
   
   In this model, the excitation and de-excitation of an electron corresponds to a pendulum swinging right to left, but in an atomic clock, the "tick" denotes an unimaginably tiny fraction of a second. 
   
   The current gold standard for time is the cesium clock, a type of atomic clock that an international body of experts has used to define what is the unit of one second: About 9.19 billion oscillations. In this clock, a microwave light source is used to excite electrons in cesium atoms. 
   
   But the new atomic clock at NIST, described in the Science study, uses a different element: Ytterbium, atomic number 70. Optical light -- specifically, yellow light from a laser with a wavelength of 578 nanometers -- is used to excite the electrons of ytterbium atoms. 
   
   Whereas scientists talk about billions of oscillations per second in the cesium clock, oscillations per second in the ytterbium clock approach one quadrillion per second, Ludlow said. 
   
   The new clock is akin to a ruler that has markers for fractions of inches, compared to a ruler that only delineates inches. The first instrument would make more precise measurements. 
   
   "You divide time into finer and finer intervals," Ludlow said. 
   
   In order to establish the precision of this clock, the scientists had to make two of them, to confirm agreement in the measurement of time. 
   
   The devices won't fit on your wrist, or even on your wall. Because of all the laser equipment and technology necessary for this level of precision, the atomic clock and all of its components occupy a space about the size of a dining room table, Ludlow said. 
   
   Efforts are under way to shrink the technology, however, particularly so that a version of it might be sent into space. 
   
   Potential uses 
   
   Researchers studying Einstein's theory of general relativity could make use of this clock to more precisely measure how time is different depending on the surrounding gravitational force. 
   
   Global positioning systems (GPS) already take this into account. Because they are farther from Earth than we are, and therefore experience less gravitational pull, their measurement of time as they orbit Earth is slightly different from what we perceive on the ground. A more precise atomic clock could measure the correctional factors even better. 
   
   Such clocks could also test alternative theories about the relationship between time and gravity. 
   
   There could be other applications for navigation and communications systems. 
   
   But you probably won't want one for your alarm clock. Ludlow said the total cost ranges on the order of a half-million dollars. 
   
   Accuracy 
   
   Although scientists have proclaimed that this is the world's most stable clock, they do not yet know as much about its accuracy. This is a subtle but important difference: The ytterbium clock has demonstrated incredible stability of measurement -- it always measures a second in the same way -- but we do not yet know if what it is measuring is a "true" second. 
   
   So, we'll have to wait to find out whether these clocks could be the most accurate in the world. 
   
   More research is needed. It's a story we hear time and time again. 
   
   Follow Elizabeth Landau on Twitter and Google+. ||||| A pair of experimental atomic clocks based on ytterbium atoms at the National Institute of Standards and Technology (NIST) has set a new record for stability. The clocks act like 21st-century pendulums or metronomes that could swing back and forth with perfect timing for a period comparable to the age of the universe. 
   
   NIST's ultra-stable ytterbium lattice atomic clock. Ytterbium atoms are generated in an oven (large metal cylinder on the left) and sent to a vacuum chamber in the center of the photo to be manipulated and probed by lasers. Laser light is transported to the clock by five fibers (such as the yellow fiber in the lower center of the photo). Credit: Burrus/NIST View hi-resolution image 
   
   NIST physicists report in the Aug. 22 issue of Science Express that the ytterbium clocks' tick is more stable than any other atomic clock. Stability can be thought of as how precisely the duration of each tick matches every other tick. The ytterbium clock ticks are stable to within less than two parts in 1 quintillion (1 followed by 18 zeros), roughly 10 times better than the previous best published results for other atomic clocks. 
   
   This dramatic breakthrough has the potential for significant impacts not only on timekeeping, but also on a broad range of sensors measuring quantities that have tiny effects on the ticking rate of atomic clocks, including gravity, magnetic fields, and temperature. And it is a major step in the evolution of next-generation atomic clocks under development worldwide, including at NIST and at JILA, the joint research institute operated by NIST and the University of Colorado Boulder. 
   
   "The stability of the ytterbium lattice clocks opens the door to a number of exciting practical applications of high-performance timekeeping," NIST physicist and co-author Andrew Ludlow says. 
   
   Each of NIST's ytterbium clocks relies on about 10,000 rare-earth atoms cooled to 10 microkelvin (10 millionths of a degree above absolute zero) and trapped in an optical lattice -- a series of pancake-shaped wells made of laser light. Another laser that "ticks" 518 trillion times per second provokes a transition between two energy levels in the atoms. The large number of atoms is key to the clocks' high stability. 
   
   The ticks of any atomic clock must be averaged for some period to provide the best results. One key benefit of the very high stability of the ytterbium clocks is that precise results can be achieved very quickly. For example, the current U.S. civilian time standard, the NIST-F1 cesium fountain clock, must be averaged for about 400,000 seconds (about five days) to achieve its best performance. The new ytterbium clocks achieve that same result in about one second of averaging time. 
   
   Given this high level of stability the ytterbium clocks can make measurements extremely rapidly -- in real time in many cases -- which could be important in rapidly changing application settings, such as the factory floor and the natural environment. 
   
   A key advance enabling the milestone performance of the ytterbium clocks was the recent construction of a second version of the clock to measure and improve the performance of the original, developed since 2003. Along the way, NIST scientists have made several improvements to both clocks, including the development of an ultra-low-noise laser used to excite the atoms, and the discovery of a method to cancel disruptive effects caused by collisions between atoms. 
   
   The ytterbium clocks' stability record is different from the performance levels previously publicized for NIST-F1, which is traceable to the international system of units, and NIST experimental optical clocks based on single ions, such as the aluminum quantum logic clock or the mercury ion clock. NIST-F1 and the ion clocks were evaluated based on systematic uncertainty, another important metric for standard atomic clocks. NIST-F1's performance is described in terms of accuracy, which refers to how closely the clock realizes the cesium atom's known frequency, or natural vibration rate. Accuracy is crucial for time measurements that must be traced to a primary standard. 
   
   NIST scientists plan to measure the accuracy of the ytterbium clocks in the near future, and the accuracy of other high performance optical atomic clocks is under study at NIST and JILA. The research is funded in part by the Defense Advanced Research Projects Agency and the National Aeronautics and Space Administration (NASA).
target: – A new timepiece the size of a dining-room table is being hailed as perhaps the world's most precise: It's "like measuring time over a hundred years to a precision of several nanoseconds," says Andrew Ludlow, co-author of a study behind what's being called the ytterbium optical lattice clock. Until now, the standard for time precision in the US has been a cesium-based clock. Some 9.19 billion oscillations of its electromagnetic signal defines a second. But the ytterbium clock oscillates about a quadrillion times per second, allowing observers to "divide time into finer and finer intervals," Ludlow notes. Those intervals are extremely regular; indeed, two of the clocks have set a record for stability, Science Daily reports. Their timing would be perfect for about as long as the universe has existed. Experts must measure the cesium clock across five days for the most precise readings, whereas the ytterbium clock requires just a second to offer the same level of precision. Why would we ever need such a thing? It could mean better GPS, for example: Because the navigation systems are in space, their time perception isn't quite the same as ours on Earth. Scientists could better correct for that using a more precise clock, CNN notes.