Where modern atomic clocks use long-wavelength microwave radiation, the next generation of atomic clocks will measure atomic changes based on visible light frequencies, filling in even more decimal places of precision for what a second is.

现代原子钟使用长波长微波辐射，下一代原子钟将根据可见光频率测量原子变化，为一秒的精度填充更多的小数位。