Keywords: Atomic Clock041.jpg Cesium the heart of the National Bureau of Standards' atomic clock is contained in a capsule before being put in the oven that will vaporize it into a beam of atoms The atomic clock counts the vibrations of these cesium atoms an incredible 9 192 631 770 per second National Institute of Standards and Technology National Institute of Standards and Technology PD-USGov-NIST PD-USGov National Bureau of Standards National Institute of Standards and Technology Atomic clocks |