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Who worked out the length of a second?

Paul Bachelor, by email

The term 'second' comes from the second division of an hour by a factor of 60 using the weird 'sexagesimal' counting system adopted by the Babylonians. The first use of so fine a division of an hour began around 1000AD, but it took almost another 600 years before clocks capable of measuring out seconds reliably became available. Today, the second is defined by a fundamental physical process - it's the time needed for a caesium atom to emit exactly 9,192,631,770 waves of a certain type of radiation. This process is measured by atomic clocks.

Comments: 1

Not so weird

Thu, 2010-06-24 22:30
M Paul Lloyd

Sorry but when it comes to calculating in base 60, degrees of the compass become really quite easy to calculate and as an old person I never saw any problem with the inch divisible by sixty.

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