Hypatia (~360 - 415)
Hypatia was born sometime between 350 and 370 AD, she was Greek but she lived in Alexandria, Egypt and also travelled to Greece and Rome to study. In her time, she was the world’s leading mathematician and astronomer and she is the earliest woman doing that kind of work that we know about. She was probably taught by her father, Theon of Alexandria, and helped with his work to preserve the mathematical and astronomical teachings of the Greek Philosophers such as Euclid and Ptolemy.
In about 400 AD, Hypatia became the head of the Platonist school at Alexandria. There she taught astronomy, mathematics and philosophy, especially the works of Plato and Aristotle. Her most important work in astronomy and science include the charting of stars and planets, the invention of the hydrometer, which is used to determine the relative density and gravity of liquids, the hydroscope (a device for looking under water) and she may also have invented the plane astrolabe, which is an ancient instrument for telling the time and to help people navigate and find their way between places.
One of her most famous students is Synesius of Cyrene who later became the Bishop of Ptolemais. None of Hypatia's written work has survived but we know of her work though the many letters that, Synesius, wrote to her and which have been preserved.
Hypatia did not act like ‘normal’ women at the time, she didn’t wear traditional women’s clothes and instead she wore cloaks and other clothing that the male scholars or teachers wore. She also drove her own chariot!