Yippe... we get more time !!
We always feel... how I wish I had more time...
Well, here is a good news, we are getting more time :)
On December 31, 2008 a “Leap second” will be added to the world’s clocks at 23 hours, 59 minutes and 59 seconds Coordinated Universal Time (UTC).
Historically, time was based on the mean rotation of the earth relative to celestial bodies and the second was defined in this reference frame. However, the invention of atomic clocks defined a much more precise “atomic time” scale and a second that is independent of the earth’s rotation. In 1970, an international agreement established two timescales: one based on the rotation of the earth and one based on atomic time.
Atomic clocks do not use radioactivity, but they use the exact frequency of the microwave spectral line emitted by atoms of the element cesium, in particular its isotope of atomic weight 133 ("Cs-133"). The integral of frequency is time, so this frequency, 9,192,631,770 hertz (Hz = cycles/second), and this provides the fundamental unit of time, which are measured by cesium clocks.The problem is that the earth’s rotation is very gradually slowing down, which necessitates the periodic insertion of a “leap second” into the atomic timescale to keep the two within 1 second of each other. The International Earth Rotation and Reference Systems Service (IERS) is the organization which monitors the difference in the two timescales and calls for leap seconds to be inserted or removed when necessary.
Well, here is a good news, we are getting more time :)
On December 31, 2008 a “Leap second” will be added to the world’s clocks at 23 hours, 59 minutes and 59 seconds Coordinated Universal Time (UTC).
Historically, time was based on the mean rotation of the earth relative to celestial bodies and the second was defined in this reference frame. However, the invention of atomic clocks defined a much more precise “atomic time” scale and a second that is independent of the earth’s rotation. In 1970, an international agreement established two timescales: one based on the rotation of the earth and one based on atomic time.
Atomic clocks do not use radioactivity, but they use the exact frequency of the microwave spectral line emitted by atoms of the element cesium, in particular its isotope of atomic weight 133 ("Cs-133"). The integral of frequency is time, so this frequency, 9,192,631,770 hertz (Hz = cycles/second), and this provides the fundamental unit of time, which are measured by cesium clocks.The problem is that the earth’s rotation is very gradually slowing down, which necessitates the periodic insertion of a “leap second” into the atomic timescale to keep the two within 1 second of each other. The International Earth Rotation and Reference Systems Service (IERS) is the organization which monitors the difference in the two timescales and calls for leap seconds to be inserted or removed when necessary.
posted by Aseem Chiplonkar at
10:44 AM
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