Jean Baptiste Joseph Delambre (September 19, 1749 in Amiens – August 19, 1822 in Paris) was a French mathematician and astronomer. September 19 is the 262nd day of the year (263rd in leap years). ... Events While in debtors prison, John Cleland writes Fanny Hill (Memoirs of a Woman of Pleasure). ... The cathedral in Amiens Location within France Amiens is a city and commune in the north of France, 120 km north of Paris. ... August 19 is the 231st day of the year (232nd in leap years) in the Gregorian Calendar. ... 1822 was a common year starting on Tuesday (see link for calendar). ... The Eiffel Tower has become a symbol of Paris throughout the world. ... A mathematician is a person whose area of study and research is mathematics. ... An astronomer or astrophysicist is a scientist whose area of research is astronomy or astrophysics. ...

Delambre was born in Amiens, France. In collaboration with Pierre Méchain, his greatest achievement was the measurement of the length of the meridian between Dunkerque and Barcelona. This portion of the meridian, which also passes through Paris, was to serve as a basis for the calculation of the length of the quarter meridian, connecting the North Pole with the Equator. The expedition lasted from 1792 to 1799. Its purpose was to establish a universally accepted foundation for the definition of the metre, which was to be defined as 1 / 10,000,000 of the distance from the North Pole to the equator. The cathedral in Amiens Location within France Amiens is a city and commune in the north of France, 120 km north of Paris. ... Pierre François André Méchain (August 16, 1744 – September 20, 1804) was a French astronomer. ... Meridian is: Meridian (astronomy): an imaginary circle perpendicular to the horizon. ... Location within France Dunkirk ( French: Dunkerque; Dutch: Duinkerke) is a harbour city and a commune in the northernmost part of France, in the département of Nord, 10 km from the Belgian border. ... Barcelona within Barcelonès Population (2003) 1,582,738 Area 1004 Km2 Population density (2001) 15,764/Km2 Barcelona is the capital of Catalonia, an autonomous region in northeastern Spain (41°23′ N 2°11′ E). ... The Eiffel Tower has become a symbol of Paris throughout the world. ... A North Pole is the northernmost point on any planet. ... The equator is an imaginary line drawn around a planet, halfway between the poles. ... 1792 was a leap year starting on Sunday (see link for calendar). ... 1799 was a common year starting on Tuesday (see link for calendar). ... The metre (American spelling: meter), symbol: m, is the basic unit of distance (or of length, in the parlance of the physical sciences) in the International System of Units. ...

Delambre crater is named for him on the Moon. Delambre is a lunar impact crater that lies to the southwest of Mare Tranquillitatis, in the central highland region. ... Crust composition Oxygen 43% Silicon 21% Aluminium 10% Calcium 9% Iron 9% Magnesium 5% Titanium 2% Nickel 0. ...

External links

• Biography (http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Delambre.html) at the MacTutor archive
• http://www.surveyhistory.org/jean_baptiste_delambre.htm