On Earth, optical clocks can divide time more finely than ever before; In space, optical clocks can be used as GPS reference points, coordinating satellites and exploring basic physics problems. Optical and atomic clocks work by measuring the vibrations of atoms as they jump from one energy level to another. Optical clocks run at a higher vibration frequency, in the visible light band, and atomic clocks in the microwave band, so they tick faster than atomic clocks.
