What time is it? One of the most frequently discussed issues around the world, but what exactly are we asking? Ask anyone in China, what time is, then you will surely get a different answer if you ask an American, of course, their time zones on the opposite side of the world.
But what if you ask two people in the same room as you? You may have the same response from both but then can again see a person one or two minutes faster.
When we ask, the time after which wereally ask is for a rough estimate for the time zone that we are in. Some watches are more accurate than others, but it is often enough for our daily needs.
But what if you need to know the exact time and what, if you know what this time to another country. Maybe you've bought a ticket, it would be disappointing, turn left at the airport only to find out that your ticket has been sold to someone else, slower than the clock on their travel agentthan the one where you bought your ticket.
How does global industry to keep accurate time with each other? The answer is quite simple and it is called Coordinated Universal Time or UTC.
The International Bureau of Weights and Measures (BIPM) acts as the official timekeeper for the world and began in 1972 after the development of the atomic clock watches.
The atomic clock was first developed in the late 50s, when it was discovered that the atom of cesium-133Response to a precise frequency of 9192631770 every second. This rate was so accurate that developed atomic clocks with an accuracy of one second year and 1.4million in the international system of units, defined the second as the frequency of the cesium-133 atom and was born of an international unit for measuring time.
However, atomic clocks are more accurate than the earth itself, which actually slows in its rotation. This deceleration is small, but if the normSystem time to UTC, do not replace all that midnight would eventually fall (in the middle of the day, although it would be a millennia or two) to take in order to compensate for leap seconds added to every few years.
The only problem is that clocks are atomic clocks Clock in size and cost tremendously. In fact, they are usually only found in large-scale physics laboratories such as NPL (National Physics Laboratory, UK) and MIT (Massachusetts Institute of Technology,U.S.).
Then, like the rest of the world to keep an eye on UTC time? The time that told about this great atomic clock via radio transmissions or the GPS satellite system (satellite navigation is dependent on UTC because without them, a satellite can not say exactly where a broadcast receiver).
Most computer networks are the UTC time, either over the Internet sycnhronised (which is not secure and only for private users) or recommended by specialized GPS or radio time server. This time serverMake use of NTP (Network Time Protocol), which were developed in the last 25 years to keep in sync computer networks, not to leave them wrong on their internal clock.
NTP server industry and the UTC have it truly global, enabling technologies such as communication satellites, mobile phones, sat-nav and keep ATMs that we all take for granted.
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