Galileo Galilei

I hold the sun to be situated motionless in the center of the revolution of the celestial orbs while the earth rotates on its axis and revolves about the sun. — Galileo Galilei Heliocentrism — the idea that the Earth and planets revolve around the sun at the center of the universe— had been around since the ancient Greeks. But it was Galileo who first provided proof using a telescope. In 1615, he was investigated by the Roman Inquisition of the Catholic Church for his supposedly heretical beliefs, and spent part of his life under house arrest. Today, he is considered the father of observational astronomy, modern physics, and the scientific method.