Aristarchus of Samos (310 -230 BC)

Aristarchus of Samos was born on the small but important and wealthy island of Samos. He is credited as the first to develop a sun-centered model of the cosmos.

He was a pupil of Strato of Lampsacus, a natural philosopher of originality, who succeeded Theophrastus as head of the Peripatetic school in 288 or 287 BC and held that position for eighteen years.

In 280/281 BC he made an observation of the summer solstice; and the book in which he formulated his heliocentric hypothesis was published.

In his little treatise On the Sizes and Distances of the Sun and Moon Aristarchus determined the rations of the Sun’s and Moon’s distances from Earth, as well as the ratios of their sizes to the size of the Earth.

He formed a triangle between the moon, Earth and sun and applied known geometry of right triangles to solve the problems.

Aristarchus was called ‘the mathematician’, doubtless in order to distinguish him from the many other persons of the same name; he is included by Vitruvius among the few great men who possessed an equally profound knowledge of all branches of science, geometry, astronomy, music etc

Aristarchus' crowning achievement was the hypothesis he put forward regarding the solar system, wherein he anticipated Copernicus.
Aristarchus of Samos (310 -230 BC)