Paris Observatory
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The Paris Observatory, a research institution of the Paris Sciences et Lettres University, is the foremost astronomical observatory of France, one of the largest astronomical centres in the world, and
Obs Paris coupole Arago
The Château-Neuf at Meudon in 1871, after the fire
Project for a dome in the heart of the Château-Neuf, never built. Circa 1880
The Meridian Room (or Cassini Room) at the Paris Observatory. The Paris Meridian is traced on the floor.
Paris meridian
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The Paris meridian is a meridian line running through the Paris Observatory in Paris, France – now longitude 2°20′14.02500″ East. It was a long-standing rival to the Greenwich meridian as the prime me
Paris Observatory
…Midsummer's Day 1667, members of the Academy of Sciences traced the future building's outline on a plot outside town near the Port-Royal Abbey, with the Paris meridian exactly bisecting the site north–south. The meridian line was used as a basis for navigation and would be used by French cartographers as their prime…
The triangulation mesh of the Anglo-French survey 1784–1790
The West Europe-Africa Meridian-arc extending south from the Shetland Islands, through Great Britain, France and Spain to El Aghuat in Algeria, whose parameters were calculated from surveys carried out in the mid to late 19th century. It yielded a value for the equatorial radius of the Earth a = 6 377 935 metres, the ellipticity being assumed as 1/299.15. The radius of curvature of this arc is not uniform, being, in the mean, about 600 metres greater in the northern than in the southern part. The
One of the 135 Arago medallions. This one is located near the Louvre Pyramid.