Who decides how long a second is? - John Kitching
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Let’s Begin…
In 1967, researchers gathered to answer a long-running scientific question: just how long is a second? It might seem obvious at first. A second is the tick of a clock, the swing of a pendulum, the time it takes to count to one. But how precise are those measurements? And what is that length based on? John Kitching digs into how we scientifically define this fundamental unit of time.
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Additional Resources for you to Explore
Did you know that many people around the world use atomic time daily? Watch this TED-Ed Lesson to learn how the GPS in your smartphone uses atomic time. You can also check the time whenever you want on the internet here.
The international definition of time, and other units, is organized by the Bureau International des Poids et Mesures (BIPM) in Sevres, France. There is also a Superhero Measurement League!
More information about time in the US can be found here.
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Meet The Creators
- Educator
- John Kitching
- Director
- Tjoff Koong
- Narrator
- Addison Anderson
- Animator
- Tezo Kyungdon Lee, Magnus Lenneskog
- Sound Designer
- Stephen LaRosa
