Streete, Thomas

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(b. Cork, Ireland [?], 15 March 1622; d. Westminster, London, England, 27 August 1689)


Streete spent most of his life in London, where he was employed as a clerk in the Excise Office under Elias Ashmole. He frequented Gresham College and numbered the leading astronomers both in England and abroad among his friends and acquaintances, often assisting them in observing eclipses, transits, comets, and other unusual astronomical phenomena. For many years Streete published highly regarded ephemerides and worked intensively on the problem of determining longitude at sea. After the great fire of 1666, he was engaged in the resurvey of London.

Streete’s most important work was Astronomia Carolina (1661). One of the most popular expositions of astronomy in the second half of the seventeenth century, it served as a textbook for Newton, Flamsteed, and Halley. Its tables, constructed from a large number of observations, were generally conceded to be the best of their time. The lunar tables, in particular, were felt to mark an advance over previous ones. The book went through many editions and continued in use well into the eighteenth century.

The Astronomia Carolina was an important vehicle for the dissemination of Kepler’s astronomical ideas, which were as yet by no means generally accepted. Kepler’s first and third laws of planetary motion were clearly stated, and it was from the Astronomia that Newton learned of them. In place of Kepler’s second law, however, Streete, using as a basis the planetary theories of Seth Ward and Ismael Boulliau, developed an equant construction in which the planets generate equal angles in equal times about the“empty”focus of the elliptical orbit. His explanation of the physical cause of planetary motion employed both Cartesian vortices and Kepler’s concept of quasi-magnetic solar attraction.


Streete’s major works are Astronomia Carolina: A New Theorie of the Celestial Motions (London, 1661); An Appendix to Astronomia Carolina (London, 1664); and The Description and Use of the Planetary Systeme (London, 1674).

There is no adequate and reliable extended account of his life and work.

Wilbur Applebaum