![An atomic clock CS2 is pictured in the time-laboratory of the Physical Technical Federal Institution (PTB) in Braunschweig, Germany, 22 October 2012. In the night from 27 to 28 October, the clocks An atomic clock CS2 is pictured in the time-laboratory of the Physical Technical Federal Institution (PTB) in Braunschweig, Germany, 22 October 2012. In the night from 27 to 28 October, the clocks](https://c8.alamy.com/comp/D5YEW3/an-atomic-clock-cs2-is-pictured-in-the-time-laboratory-of-the-physical-D5YEW3.jpg)
An atomic clock CS2 is pictured in the time-laboratory of the Physical Technical Federal Institution (PTB) in Braunschweig, Germany, 22 October 2012. In the night from 27 to 28 October, the clocks
![Caesium atomic clocks from the PTB institute, Lower Saxony, Germany, Brunswick, Lower Saxony, Germany Stock Photo - Alamy Caesium atomic clocks from the PTB institute, Lower Saxony, Germany, Brunswick, Lower Saxony, Germany Stock Photo - Alamy](https://c8.alamy.com/comp/E0H17Y/caesium-atomic-clocks-from-the-ptb-institute-lower-saxony-germany-E0H17Y.jpg)
Caesium atomic clocks from the PTB institute, Lower Saxony, Germany, Brunswick, Lower Saxony, Germany Stock Photo - Alamy
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