Scientists are exploring a new type of optical atomic clock based on ytterbium-173 ions that could help define the future standard for measuring time.
Add Yahoo as a preferred source to see more of our stories on Google. Daylight saving time begins Sunday, March 8, when clocks across most of the United States "spring forward" one hour at 2 a.m.
Some results have been hidden because they may be inaccessible to you
Show inaccessible results