Hypatia of Alexandria and her friends.

Hypatia of Alexandria (370 – 415) was a Greek philosopher who lived in Alexandria (Egypt, Roman Empire). She was the best in mathematics and astronomy in her time.
Hypatia wrote about Euclid (300 BC), who also had lived in Alexandria seven centuries before. He was a Greek mathematician know as the "Father of Geometry." He wrote a book called “Elements” which has been the most influential work in the history of mathematics. It is about geometry, perspective, conic sections, spherical geometry, number theory, etc.
She knew Aristarchus of Samos (310-230 BC) theories about the heliocentric model of the solar system, with the Sun in the center of the universe.
Hypatia also wrote about Eratosthenes of Cyrene (195 BC), who was a very good friend of Arquimedes. Eratosthenes was a Greek mathematician, geographer and astronomer. He was the first who exposed a system of latitude and longitude to represent the Earth. He also calculated the circumference of the Earth with great accuracy. Do you want to know how?
But this tradition had begun with Pythagoras of Samos (570- 495 BC), a Greek philosopher known as "the father of numbers” He was a great mathematician and scientist. Do you know what the Pythagorean teorema is?