Chronology is the study of passing time. Time is a difficult concept to understand and it is really only since the advent of Einstein that we've begun to understand what exactly the time. Instead of being constant throughout the universe, time is relative which means he can vary the speed and location of different observers.
In order of chronology, time is simply the distance between two events. As we all live in the same environment, it is rare that the weather can change that if we move away from the gravity of Earth time goes slightly faster. This fact is taken into account by the navigation satellite, but we'll talk later.
The countdown began at the same time as the development of human civilization. Civilization factors related to agriculture, religion and others have created a need to know the time. The ancients used various methods to find the time: ranging from sundials to water clocks, and even more elaborate structures such as Stonehenge knew that predict solstices.
We soon realized that the timing cycles of the earth, moon and sun could all be used to communicate the time because it was apparent that the celestial motions were also accurate.
Only in middle age that humans have developed technology that knew the time to measure precisely. Mechanical clocks (which used a speed and an exhaust folio) were the first clocks and they have become more accurate since they have been added a pendulum. With mechanical clocks, men could for the first time ever live in a synchronized manner, going to meetings and festivals "at the same time."
The next big step in the sequence was represented by the development of electronic clocks. These clocks operated by an electric charge passing through the crystal (as quartz) and using the vibration (or resonance) as a measure of time. The electronic clocks have been proved incredibly accurate, but only with the development of atomic clocks in the 50s that the real accuracy began to emerge.
The atomic clock uses a resonance with a single atom (cesium traditionally has more than 9 trillion ticking every second). This large number of tic-tac resonance that are unchanged means that if an electronic clock does not derive a second weekly, atomic clocks are so accurate that they do not derive a second over hundreds of millions years.
This precision is so high that it shows the inaccuracies of the earth's rotation. This slows down due to the effects of lunar gravity as the "leap second" is added to the measure of universal time UTC (Coordinated Universal Time) so that it maintains relative to GMT (Greenwich Meantime) and to prevent drift graduated from night to day (which would normally take many millennia).
The atomic clocks that provide a level of very high precision may seem unnecessary but without the technology of satellite navigation is impossible. Satellite navigation such as GPS (Global Positioning System) works by triangulating signals schedules.
In addition, as the GPS satellites circling around the earth, they must also take into account the gravitational forces are weak. This means that atomic clocks on board GPS satellites operate at a time that differs slightly from those who are on earth.
The atomic clocks are used worldwide to provide a synchronization schedule that provides very high accuracy. Most computer networks use time servers to synchronize. This will be an NTP (Network Time Protocol). These time servers dedicated to receiving a signal from a time TUC radio transmission through the atomic clocks laboratories such as NIST or NTP or a GPS time server.
Using a GPS NTP server or a dedicated radio with a reference time server on a network, computers can be synchronized in the world at the right time: UTC time ..
In order of chronology, time is simply the distance between two events. As we all live in the same environment, it is rare that the weather can change that if we move away from the gravity of Earth time goes slightly faster. This fact is taken into account by the navigation satellite, but we'll talk later.
The countdown began at the same time as the development of human civilization. Civilization factors related to agriculture, religion and others have created a need to know the time. The ancients used various methods to find the time: ranging from sundials to water clocks, and even more elaborate structures such as Stonehenge knew that predict solstices.
We soon realized that the timing cycles of the earth, moon and sun could all be used to communicate the time because it was apparent that the celestial motions were also accurate.
Only in middle age that humans have developed technology that knew the time to measure precisely. Mechanical clocks (which used a speed and an exhaust folio) were the first clocks and they have become more accurate since they have been added a pendulum. With mechanical clocks, men could for the first time ever live in a synchronized manner, going to meetings and festivals "at the same time."
The next big step in the sequence was represented by the development of electronic clocks. These clocks operated by an electric charge passing through the crystal (as quartz) and using the vibration (or resonance) as a measure of time. The electronic clocks have been proved incredibly accurate, but only with the development of atomic clocks in the 50s that the real accuracy began to emerge.
The atomic clock uses a resonance with a single atom (cesium traditionally has more than 9 trillion ticking every second). This large number of tic-tac resonance that are unchanged means that if an electronic clock does not derive a second weekly, atomic clocks are so accurate that they do not derive a second over hundreds of millions years.
This precision is so high that it shows the inaccuracies of the earth's rotation. This slows down due to the effects of lunar gravity as the "leap second" is added to the measure of universal time UTC (Coordinated Universal Time) so that it maintains relative to GMT (Greenwich Meantime) and to prevent drift graduated from night to day (which would normally take many millennia).
The atomic clocks that provide a level of very high precision may seem unnecessary but without the technology of satellite navigation is impossible. Satellite navigation such as GPS (Global Positioning System) works by triangulating signals schedules.
In addition, as the GPS satellites circling around the earth, they must also take into account the gravitational forces are weak. This means that atomic clocks on board GPS satellites operate at a time that differs slightly from those who are on earth.
The atomic clocks are used worldwide to provide a synchronization schedule that provides very high accuracy. Most computer networks use time servers to synchronize. This will be an NTP (Network Time Protocol). These time servers dedicated to receiving a signal from a time TUC radio transmission through the atomic clocks laboratories such as NIST or NTP or a GPS time server.
Using a GPS NTP server or a dedicated radio with a reference time server on a network, computers can be synchronized in the world at the right time: UTC time ..
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