The Humble Second: We Can Now Measure It To Incredible Precision, It's Continually Fluctuating, It's Getting Longer, And It's Stuck In 1957. All Because Of The Moon - Quill & Pad

There are two ways to define a day: astronomically by measuring the time between midday to midday and by using a manmade clock. The difference between them is that the length of the former fluctuates while the latter remains fixed. As Ian Skellern explains, t…

The latest generation of optical atomic clocks are accurate to less than one-tenth of a second over the age of the universe (13.8 billion years). So why are they still measuring the length of a secon… [+11777 chars]

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