Leap Second: 2015 Will Be One Second Longer Extr
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Extra Second To Be Added On June 30
Internet, software and computer engineers are preparing themselves for problems they could face with their systems after the International Earth Rotation and Reference Systems (IERS) announced earlier in the year that an extra second — a leap second — will be added to clocks on June 30 to account for the difference between solar time measured by the Earth’s rotation and time measured by atomic clocks.
The extra second will be added at midnight coordinated universal time (UTC), 8 p.m. EDT in the U.S.
What this means is that the year 2015 will be longer by a second.
There are fears that computer systems and software not equipped to accommodate the adjustment could have issues. The problem is similar to the so-called Y2K bug challenge at the beginning of the century due to transition from a system in which the year was abbreviated to two digits to one in which the year was represented with four digits (“2000″).
Experts say that the need for a leap second adjustment arises because the Earth’s rotation is gradually slowing down by about two-thousandths of a second every year compared with atomic clocks which keep constant and accurate time.
On June 30, the leap second adjustment to coordinated universal time (UTC) means that atomic clocks will go from 23:59:59 to 23:59:60, instead of to 00:00:00. The procedure means effectively that clocks pause for a second before finally going to 00:00:00.
The one-second pause is to allow the Earth’s rotation to catch up with atomic time.
Already, computer software and Internet companies are bracing themselves for the problems that their systems could develop when a leap second is added. The last time a leap second was added in June 2012, several Internet software and websites, such as Mozilla, LinkedIn, Reddit and Stumbleupon experienced problems.
The Network Time Protocol (NTP) that many computing systems use is designed to keep time with atomic clocks and not with the Earth’s rotation. They are also not designed to accommodate adjustments involving adding an extra second due to the slowing down of the Earth’s rotation.
But some Internet companies have devised their own solutions to the problem.
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