SI Unit of Time

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USA, Canada clocks on Daylight Saving Time until 4 November 2012 at 2am local time
UK / Europe: Clocks on Daylight Saving (Summer) Time until: Sunday 28 October 2012 01:00 (1am) GMT


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What is the SI unit of time?

Official definition of a second

In 1967 a new SI definition of a second was created based on the radiation from the caesium-133 atom.

It is correctly defined as "the duration of 9,192,631,770 periods of the radiation corresponding to the transition between two hyperfine levels of the ground state of the caesium-133 atom."
News:

USA & Canada clocks
on Daylight Saving Time until:
Sunday 4 November 2012 2am local time

Europe / UK clocks
on Daylight Saving Time until:
Sunday 28 October 2012 01:00 GMT

Australia clocks
on Standard Time until:
Sunday 7 October 2012 3am local time

Related Websites:
Time in

USA + Canada
Atlantic Time (Canada) | Eastern Time (EST) | Central Time (CST) | Mountain Time (MT) | Pacific Time (PST) | Alaska Time (AKST) | Hawaii Time (HST) | Daylight Saving Time (DST)

Europe
Central European Time (CET) | Eastern European Time (EET) | Western European Time (WET) | British Summer Time   (BST)

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China Time (CST) | India Time (IST) | Japan Time (JST)

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St Helena | Burkina Faso | Gambia | Ghana | Guinea | Guinea-Bissau | Ivory Coast | Liberia | Mali | Mauritania | Morocco | Sao Tome | Senegal | Togo | Western Sahara
 
 

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Greenwich Mean Time

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SI Unit of Time