'''Thomas Harriot''' (c. astronomer, mathematician, ethnographer, and translator. Some sources give his surname as '''Harriott''' or '''Hariot'''.  He is sometimes credited with the introduction of the potato to Great Britain and Ireland<ref>[http://www.btinternet.com/~richard.towers/jim/raleigh1.html]</ref>

After graduating from the Raleigh, and on his return he worked for the 9th Earl of Northumberland. At the Earl's house, he became a prolific mathematician and astronomer to whom the theory of refraction can be attributed.

==Biography==

Born in 1560 in astronomy/astrology to provide navigational expertise. Harriot was also involved in designing Raleigh's ships and served as his accountant as well. During this time he also wrote a treatise on navigation prior to his expedition with Raleigh.<ref>Jehlen, Myra & Michael Warner. (1997) ''The English Literatures of America, 1500-1800'', Routledge (UK). p. 64. ISBN 0-415-91903-7.</ref>

===Expedition to the Americas===

He made only one expedition, around 86, and spent some time in the New World visiting Native American population encountered by the expedition; it proved very influential upon later English explorers and colonists. He wrote: "Whereby it may be hoped, if means of good government be used, that they may in short time be brought to civility and the embracing of true religion."  At the same time, his views of Native Americans' industry and capacity to learn were later largely ignored in favor of the parts of the "Report" about extractable minerals and resources.

As a scientific adviser during the voyage, Harriot was asked by Raleigh to find the most efficient way to stack cannon balls on the deck of the ship. His ensuing theory about the close-packing of spheres shows a striking resemblance to atomism and modern atomic theory of which he was later accused of believing. His correspondence about optics with Johannes Kepler, in which he described some of his ideas, later influenced Kepler's conjecture.

===Later years===

He was dedicated to work for Henry Percy, 9th Earl of Northumberland with whom he also resided at the Syon House, which was run by Henry Percy's cousin Thomas Percy.

Harriot's sponsors began to fall from favour: Raleigh fell from favour, and Harriot's other patron Henry Percy, the Ninth Earl of Northumberland, was imprisoned in 1605 in connection with the Thomas Percy. 

Harriot himself was interrogated and briefly imprisoned but soon released. Walter Warner, Robert Hues, William Lower and other scientific peers were present around the Earl of Northumberland's mansion as they worked and lent a hand in the teaching of the family's children.<ref name=Stedall />

Halley's Comet in 1607 turned Harriot's attention towards astronomy.  His observations of August 1609 and subsequent observations may have been the first uses of a telescope for astronomy. He was the first man to attempt mapping of the Moon, and also to observe sunspots, in December 1610. 

thumb|300px|La baie de Pamlico, dessinée par [[John White (colon)|John White (1590). Harriot y passa une année à explorer la Virginie et à étudier la culture et les mœurs des Algonquins.]]

'''Thomas Harriot''' est un anglais, né à Oxford en 1560 et décédé le 2 juillet 1621 à Londres.

== Biographie ==
Élève de Saint-Domingue (1586).

Il mit au point une grammaire de l'algonquin, dont il ne subsiste que quelques feuillets. Il publia le récit de son séjour dans son seul livre, ''A Briefe and True Report of the New Found Land of Virginia'' (1588).

En tant que géographe, il étudia surtout la trigonométrie sphérique et établit la théorie mathématique de la projection que Gerardus Mercator n'avait construite que par des tracés approchés.

Il étudia l'algèbre avec algébrique anglaise.

Athée notoire, protégé de Walter Raleigh, puis du Comte de Northumberland Henry Percy, des spécialistes d'histoire élisabéthaine (Bradbrook par exemple) l'ont soupçonné d'avoir été membre d'une École de la Nuit.

Lors de la loi des sinus en optique, mais ne la publia pas. Informé des recherches de Galilée, il fut le premier en Angleterre à utiliser une lunette astronomique, avec laquelle il observa et dessina les cratères lunaires et les évolutions des ''planètes médicéennes''<ref>On désignait ainsi les satellites de Jupiter au début du XVIIe siècle.</ref> (1610-1611). Il dessina également les taches solaires, qu'il observait à l'œil nu.

Thomas Harriot manifesta en 1618 les premiers symptômes d'un cancer des fosses nasales, dont il nota lui-même l'évolution jusqu'à sa mort.