Hipparchus was a Greek astronomer, geographer, and mathematician. He is considered the founder of trigonometry, but is most famous for his incidental discovery of the precession of the equinoxes. Hipparchus was born in Nicaea, Bithynia, and probably died on the island of Rhodes, Greece. He is known to have been a working astronomer between 162 and 127 BC. 190 BC – 120 BC; died at about 70. Alive at the same time as Cato the Elder, Terence, Posidonius, Apollonius of Perga, and Sulla. Wiki link