Jean Picard

Jean Picard

Born: 21 July 1620 in La Flèche, France
Died: 12 Oct 1682 in Paris, France

Previous (Chronologically) Next     Biographies Index

Previous ( Alphabetically) Next          Welcome page
Jean Picard worked with Gassendi for some time and helped him with observations of a solar eclipse on 21 August 1645. In 1655 Picard became professor of astronomy at the Collège de France in Paris. He was a founding member of the Académie Royale des Sciences in 1666.

He devised a micrometer to measure the diameters of celestial objects such as the Sun, Moon and planets. He greatly increased the accuracy of measurements of the Earth which appear in Mesure de la Terre (1671). These were used by Newton in his gravitational theory.

In the same year he went to Tycho Brahe's observatory at Hven Island in Sweden so that its location could be determined accurately and so Tycho observations could be directly compared with others. In 1673 Picard moved to the Paris Observatory where he collaborated with Cassini, Römer and, slightly later, with La Hire.

References:

  1. Dictionary of Scientific Biography
  2. Biography in Encyclopaedia Britannica
  3. J A N de Condorcet, Éloges des académiciens de l'Academie Royale des Sciences (1773), 36-48.
  4. C Wolf, Histoire de l'observatoire de Paris de sa fondation à 1793 (Paris, 1902) .
  5. G Picolet (ed.), Jean Picard et les debuts de l'astronomie de precision au XVIIe siecle : actes du colloque du tricentenaire (Paris, 1987). 
Previous (Chronologically) Next     Biographies Index

Previous ( Alphabetically) Next          Welcome page

History Topics Index              Famous curves index

Chronologies                           Birthplace Map

Mathematicians of the day  Anniversaries for the year

Search Form   Simple Search Form   Search Suggestions
JOC/EFR February 1996