[T]he second was redefined as the duration of 9,192,631,770 energy transitions of the cesium atom…
This change took place in 1967.
Why 60 seconds and minutes but 24 hours? via Kottke.org
[T]he second was redefined as the duration of 9,192,631,770 energy transitions of the cesium atom…
This change took place in 1967.
Why 60 seconds and minutes but 24 hours? via Kottke.org