Reference time at odds with astronomical due to changes in the Earth's rotation. Over the last thousand years
passed over difference of about ten minutes. On the night of July 1, 2015 all of the atomic clock in the world stop for a second. Last day of June last 86401 instead of 86400 second - one second more than twenty-four hours.
Photo starry sky with a slow shutter speed. Ben Canales i>
Mechanical clocks are not accurate enough to measure the effect of a change to the time difference of the order. Atomic clocks discovered this problem. From 1987 on this issue runs the International Earth Rotation Service, which evaluates the angular velocity of rotation of the planet, and takes into account the effects of the periodic deflection of the earth's axis. Organization calculates corrections and adds additional second December 31 June 30 or whenever the difference of the reference time from astronomical approaches 0 and 9 seconds. Since 1972, an additional 25 were administered a second time.
Прецессия Earth on the scale of 1000 years:
In 2012, the java-application servers Mozilla Corporation зависли because of the addition of an extra second. Two and a half hours of the server is not operating normally. From half an hour to several hours not worked sites Yelp, LinkedIn, Gizmodo, FourSquare, Gawker, Amazon and many others.
Google remained available. Company подготовилась to this situation. For correct operation of the server time must be synchronized and always go forward. For amendments to a second clock usually transferred to a second ago at the end of the day. But the repeated second, write a blog post Google, can cause problems. What will happen to the operations to be carried out during this second? Similarly, whether to save e-mail? What happens to all the servers? In 2005 with the introduction of an additional second server is not running. Instead of adding a second Google continually adjusts the time - a few milliseconds, ie introduces additional time each day.
Similarly to the situation приготовились Japan, Australia, South Korea and Singapore stock exchanges. In New York, will introduce a second at eight o'clock local time - the exchange at this point is simply closed. Nasdaq will cease trading at 7:48 am and turn off at 7:55.
Illustration Bloomberg
Source: geektimes.ru/post/252756/