Sunday 1 July 2012

What you did with the extra second?


Photo Credit by NASA


“At the time of Dinosaurs the earth completes its whole rotation in 23 hours” says Mac Milan who works at NASA. And in the year 1820, earth completes its rotation first time in 24 hours.
Is Our Earth getting older?

The Answer is somewhat yes. According to Scientist
“The influence of our nearby large moon causes our planet’s rotation, or spin, to slow down continuously. Roughly every 100 years, the day gets about 1.4 milliseconds longer. That’s 1.4 thousandths of a second. It’s not much, but it adds up.”
Leap Second:
In keeping up with the Coordinated Universal Time, 61 seconds instead of 60 were added at the end of the day on Saturday. Normally, the clock would move from 23:59:59 to 00:00:00 the next day. Instead, at 23:59:59 on June 30, UTC will move to 23:59:60, and then to 00:00:00 on July 1. In practice, this means that clocks in many systems will be turned off for one second.
The so-called leap second was added to electronic clocks at midnight universal time on Saturday. Don’t worry it just a second and it will not disturb your schedules. :)
Moreover NASA says:
‘Originally, leap seconds were added to provide a UTC time signal that could be used for navigation at sea. This motivation has become obsolete with the development of GPS (Global Positioning System) and other satellite navigation systems. These days, a leap second is inserted in UTC to keep it within 0.9 seconds of UT1.’
UT1 is officially computed from VLBI measurements, which rely on astronomical reference points and have a typical precision of 5 microseconds, or 5 millionths of a second, or better.
Very Long Baseline Interferometry (VLBI) is a technique which combines the observations from many telescopes located at various points on Earth’s surface. When it comes to timekeeping, VLBI relies on quasars – the most distant known objects in the universe – to provide a reference point in space.
Disputes on it:
Opponents of the leap second want a simpler system that avoids the costs and margin for error in making manual changes to thousands of computer networks. Supporters argue it needs to stay to preserve the precision of systems in areas like navigation (involves the determination of position and direction mostly marine navigation and land navigation).
So tell me, How did you use that extra second?
I sleep for an extra second! :D
you can read this on my WP-Blog.

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