U.S. scientists have unveiled an experimental atomic clock they say is so precise it would neither gain nor lose 1 second in about 5 billion years. A research group led by a National Institute of Standards and Technology physicist says the experimental strontium clock has set new world records for both precision and stability, key measurements of such a clock. The clock is in a laboratory at the Joint Institute for Laboratory Astrophysics, operated by the NIST and the University of Colorado Boulder on the university's campus. The JILA strontium lattice clock is about 50 percent more precise than the record holder of the past few years, NIST's quantum logic clock, the researchers reported in the journal Nature. Inside the clock, a few thousand atoms of strontium are held in a column of about 100 pancake-shaped traps called an optical lattice formed by intense laser light. Scientists detect the strontium atoms' "ticks" -- 430 trillion per second -- by bathing the atoms in very stable red laser light at the exact frequency that prompts the atoms to switch, or "tick," between energy levels. "We already have plans to push the performance even more," NIST/JILA Fellow and group leader Jun Ye said. "So in this sense, even this new Nature paper represents only a 'mid-term' report. You can expect more new breakthroughs in our clocks in the next five to 10 years."