HIPPARCHUS

     Hipparchus, better known as Hipparchos was a Greek mathematician born in 190 BC. Not much is known about Hipparchus’s life however it is deduced that his place of birth was Nicaea in Bithynia which is modern day Turkey. Though being one of the most influential mathematicians and astronomers, the details of his work are very scarce the most definite survived piece being his commentary on a poem by Aratus from the 3rd century the ‘Commentary on the Phainomena of Eudoxus and Aratus’. Also in the list of his contributions are his books on optics and arithmetic, writings concerning geography and astrology and a treatise called ‘On Objects Carried Down by their Weight’. 

Contribution to mathematics:

         His contributions to astronomy are believed to be of significant use in modern day applications of the field. Being the first to calculate a heliocentric system he left his work as according to his calculations the orbits were not truly circular as was the belief of science of that time. Hipparchus had observed the stars from a time span of 147 to 127 BC using an instrument called ‘dioptra’. Some historians suggest that he was the inventor of ‘Planispheric Astrolabe’, an astronomical device. It was none other than Hipparchus who raised important questions such as what the length of a year was and what the lunar distances were. Curious to find an answer, Hipparchus extensively studied the solar and lunar motions and their orbits using several calculations and techniques. He also determined the distances and sizes of both the sun and moon.