Why Atomic Clocks Win
How can a clock be wrong by less than a second in millions of years?
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Quarky is writing this for you...
Your turn!
Question 1 of 2What does an atomic clock count?
The story
Quarky's wristwatch keeps drifting, and he misses the big rocket launch by a whole minute. So he goes looking for the most patient timekeeper in the universe. Inside an atomic clock, tiny cesium atoms hum at exactly the same beat, over and over, forever. Quarky counts along with them: 9,192,631,770 hums make one second, every single time. Springs stretch and pendulums swing differently when it is hot or cold, but atoms never change their tune. That is why atomic clocks run the internet, guide rockets and keep every phone map pointing the right way.
What you'll learn
- Atoms vibrate at one exact, unchanging frequency
- One second is defined by counting those atomic beats
- Spring and pendulum clocks drift with heat, cold and bumps
- Atomic clocks keep GPS, phones and the internet in step
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