The Greenwich Observatory, which had a long royal status, has become the main astronomical organization not only in the UK, but also in the world.
The initiator of its creation was Charles II. The main purpose of the creation was to clarify the geographical coordinates important for sailors. Scattered data on the location of geographical points often became the cause of the loss and even death of ships.
The Greenwich Observatory was to become the very unifying link on which sailors could rely. The data collected and processed would make it easier to navigate the expanses of the seas and oceans and find a way even when deviating from the course.
The basis of the measurement was established longitude, - the geographical coordinate used to calculate the distance between the location of a person and another specific point.
Calculation of longitude on land was not difficult - by then geodetic instruments had already appeared. But on the sea (or ocean) the use of the usual methods was not possible, since distinctive objects were not located on the surface of the water. A reliable method for determining longitude in the seas did not exist until the eighteenth century.
England, as a sea power, was actively looking for ways to determine longitude precisely in open water.
Of course, one could be guided, as before, by the stars. But this was clearly not enough. And these landmarks in cloudy weather and in fog did not work.
In 1675 (in March), Charles the Second appointed John Flamstead as royal astronomer. The young 28-year-old pastor is instructed: "… with special diligence and thoroughness, begin to reconcile the tables of the movement of heaven and the location of the stars and improve the art of navigation …".
In the same year (in March), the Greenwich Observatory began work. The results of observations are published in the first “Marine Almanac” only two years after the start of observations.
The colossal work carried out at the Greenwich Observatory literally reverses maritime navigation and gives Britain the opportunity to become the main compiler of marine (seafaring) charts.
However, many countries continued to use their own longitude measurement systems.
Italy focused on the meridian in Naples, Switzerland - in Stockholm, Spain - in Ferro, France - in Paris. But the need for a unified world reference system for determining time and longitude was obvious.
In this regard, it was decided to organize an International Conference (1884). For a month, representatives of twenty-five countries could not find a compromise. In the end, the starting point was Greenwich in London, now also known as the Greenwich meridian. They decided to measure longitude in two directions - positive (eastern longitude) and negative (western).
Street lighting in London became too bright by 1930, and further observation of the stars in the previous mode was no longer possible. The Greenwich Observatory moved to Herstmonso (Sussex, 70 km from the former location of the observatory). The remaining complex of buildings was transferred to the National Maritime Museum. In 1990, astronomers had to move again, already to Cambridge. In 1998, the Greenwich Observatory (Royal) was closed.
