Atomic Clocks
Atomic clocks are very precise and have nearly no clock drift. The rotation of the Earth itself actually is less precise than modern atomic clocks used as time standards. Thus to keep the Coordinated Universal Time (UTC) in line with the Earth's rotation, a leap second is added to some years.
Read more about this topic: Clock Drift
Famous quotes containing the words atomic and/or clocks:
“One has to look out for engineers—they begin with sewing machines and end up with the atomic bomb.”
—Marcel Pagnol (1895–1974)
“Weighing the steadfastness and state
Of some mean things which here below reside,
Where birds like watchful clocks the noiseless date
And intercourse of times divide,”
—Henry Vaughan (1622–1695)