Hipparchus Hipparchus of Nicaea, was a Greek astronomer, geographer, and mathematician. He is considered the founder of trigonometry but is most famous for his incidental discovery of precession of the equinoxes. He was born in İznik, Turkey in the year 190 BC. His life ended when he died in Rhodes, Greece in the year 120 BC. As a young man, Hipparchus made records of his local weather patterns throughout the entire year. He made weather calendars (parapēgmata), they synchronized the onset of winds, rains, and storms with the astronomical seasons and the risings and settings of the constellations, that were produced by many astronomers from as early as the 4th century BC. Hipparchus had written many books, and only one of them are still