Bernard Guinot
Bernard René Guinot was a French astronomer. He is known for his contributions to the establishment of temps atomique international (TAI) and the geodetic reference system used in satellite navigation.
Biography
From 1945 to 1952, Guinot served as an officer in the Messageries Maritimes. In 1952 he became an astronomer at the Paris Observatory, where he worked with André Danjon on applications and further developments of the Danjon prismatic astrolabe. The applications were especially concerned with precise determinations of polar motions and variations in the Earth's rotation. In 1958 with a dissertation on applications of the Danjon astrolabe, Guinot obtained his doctorate from the University of Paris. He continued his employment as an astronomer at the Paris Observatory until 1990. From 1984 to 1992 he was a physicien principal, and then a consultant, at the Bureau international des poids et mesures.Guinot served as a committee member for several commissions of the International Astronomical Union and from 1961 to 1967 was the president of the IAU's Commission 19 Rotation of the Earth. He served as president for several organizations: the Conseil scientifique du service international du mouvement du pôle from 1962 to 1970, the Fédération des services d’astronomie et de géophysique from 1970 to 1972, and the Bureau des longitudes from 1984 to 1986.
On the 1st of October 1964, as the successor to Nicolas Stoyko, Guinot became the director of the Bureau International de l'Heure (BIH) and continued his directorship until the BIH ceased to exist in 1988. From 1975 to 1979 he was the director of the Laboratoire primaire du temp et des frequencies.
In 1979 in the paper Basic problems in the kinematics of the rotation of the Earth, Guinot proposed the use of a new equatorial origin, the "non-rotating origin", for defining the Earth rotation angle in the Earth's axial tilt as the basis for Universal Time. He made important contributions to research on the measurement of time, to international cooperation in establishing standards for the measurement of time, and to organization networks for measurements in variation of Earth's rotation. He was one of the leading organizers of world-wide time metrology, networks for time comparison, and time dissemination for various users. He did research on the reliability of atomic time scales that use networks of clocks. He and his colleagues worked on a number of space experiments, such as determining the position of the Earth's pole using Doppler tracking of artificial satellites. He collaborated in research on determining the radial velocities of Mercury, studying movements in the atmosphere of Venus by spectroscopic methods, and measuring the time of a round trip from the Earth to the Moon and back of a reflected light pulse.
In July 1958 Bernard Guinot married Claudine Caillet. They had three sons.