Aren't there times that this question pops into our minds? Why this particular location to be the center of world time and not another city, e.g. Athens or Madrid? This choise wasn't given in random.
When created in 1675, the Greenwich Observatory was not to record the time, but to solve problems involving the
longitude of the sea. In doing so, the first thing to do was to verify the hypothesis that the rate of rotation of the Earth is flat.
To achieve this, 2 impactor-clocks were used to record the time in Greenwich.Using thes eclocks as reference , maps were created with the stars,in order to identify any shifts of them.
To achieve this, 2 impactor-clocks were used to record the time in Greenwich.Using thes eclocks as reference , maps were created with the stars,in order to identify any shifts of them.
So (incorectlly) was decided that Earth's rotation is constant and created naval maps for all longtitudes, with reference point the Greenwich.
By 1770, all navigators used these maps, therefore when the time came to choose the prime meridian (longitude 0) the choice was the Greenwich, as the starting point both for longitude and for the year.( Meridian Conference-Washington, 1884).
Many years later, in late 1940, it was discovered that the Earth is reduced or increased speed hence the sky during the night was still not stable.
Therefore, in 1986 the Coordinated Universal Time (UTC) became the preferred global time. The coordination is based in Paris and is based on clocks' measurements in 25 countries worldwide.
Source:coolweb.gr
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