Measuring distances has always been part of everyday life. But there was not always a unit of measurement that was equally valid for everyone. For most of human history, even the smallest regions had their own units with which to measure things. Be it feet or inches, it doesn’t take any imagination to realize that if you don’t have a common ground and it’s pretty impractical. So, who determined how long a meter is and where did the ‘meter’ come from?
Today we have the meter which marks the same distance in Paris as in Beijing. But this unit of measurement hasn’t been around for that long, so where does the meter measurement come from and who determines how long a meter is? The meter began its triumphant advance in France in the 18th century. In 1791, the French National Assembly decided to introduce a unit of length that was universally valid.
Even if it wasn’t called a meter back then, the ‘Meter project’ was born with it. The new unit of length was to be based on the circumference of the earth. It was decided to take the ten-millionth part of an earth meridian quadrant as a basis which is the distance from the North Pole to the equator.
The problem with that was that back then, people didn’t know the exact distance. So they sent two astronomers, one to Barcelona and one to Dunkirk. Jean-Baptiste Joseph Delambre and Pierre Méchain had the task of precisely determining the distance between these two places as part of this expedition.
On this basis, the earth meridian quadrant would be calculated correctly. There were a few complications in the turmoil of the French Revolution, but the two eventually managed to successfully complete their mission after seven years. Finally, in 1799, an original meter was made from platinum, which from then on was to serve as a benchmark.
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Speed Of Light As A Yardstick – Where did the meter come from?
In the19th century, it became possible to survey the earth more precisely. It turned out that the calculations were off by 0.2 percent and the original meter was a bit too short. Nevertheless, it was decided to hold on to it and henceforth defined the meter no more than ten-millionth part of the earth’s meridian quadrant. Rather, it was decided to define a meter, as the length of the concrete object, the original meter. In retrospect, the definition based on the circumference of the earth proved to be difficult anyway, since this value is not the same in every place in the world. Because the earth is not a perfect sphere.
In 1983 the definition of a meter, which is still valid today, was finally established. They wanted to kill two birds with one stone by choosing the speed of light as a reference point. Until then, this was measured, so it changed with improved measurement methods. Now, however, the decision was made to define it firmly and the meter as well. Accordingly, one meter is the distance that light travels in a vacuum in the 299,792,458th part of a second.
The metric system has spread worldwide from France. Today, there are only three countries where the meter system of measurement is not mandatory. They are Liberia, Myanmar, and the USA.