Anonymous ID: fc515e Dec. 20, 2018, 11:54 a.m. No.4394998   ๐Ÿ—„๏ธ.is ๐Ÿ”—kun

>>4394962

What Is International Atomic Time (TAI)?

 

How is TAI Measured?

 

International Atomic Time is an extraordinarily precise means of time-keeping. Atomic clocks deviate only 1 second in up to 100 million years.

 

The secret to this impeccable precision is the correct measurement of the second as the base unit of modern time-keeping. The International System of Units (SI) defines one second as the time it takes a Cesium-133 atom at the ground state to oscillate exactly 9,192,631,770 times.

 

Atomic clocks are designed to detect this frequency, most of them today using atomic fountains; a cloud of atoms that is tossed upwards by lasers in the Earth's gravitational field. If one could see an atomic fountain, it would resemble a water fountain.

 

https://www.timeanddate.com/time/international-atomic-time.html