The world’s most accurate clocks

In 1967, researchers gathered to answer one question: how long is a second? It might seem obvious. A second is the tick of a clock or the swing of a pendulum. But how precise are those measurements? And what is that length based on?

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Activities

  1. Do you think life would be better or worse if we stopped using clocks altogether? Think about your answer and discuss it with members of your household.
  2. Write a script for a film about a day when time starts moving backwards.