The super-clocks that define what time it is
The super-clocks that define what time it is Getty Images How do we know what time it is. So while the world's best timekeepers could claim greater accuracy than the average watch or grandfather clock, they themselves were wrong about the "true" time. Atomic clocks keep time far more accurately than any clock based on Earth's rotation – so accurate in fact, that if we fully based our world on them, eventually time would depart from night and day, so that the Sun would rise at 18:00 in the evening. Getty Images An early atomic clock "maser", in the mid-1950s The hydrogen masers at NPL in London are some of the world's most important atomic clocks. The thing is, though, TAI is still a construct of a hypothetical "true" clock time: a measurement that the world is merely agreeing to keep to.
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The most accurate clock in the universe[2]- Chinadaily.com.cn
The most accurate clock in the universe[1]- Chinadaily.com.cn
The most accurate clock in the universe[1]- Chinadaily.com.cn