- Aristarchus of Samos is believed to be the first person to suggest that Earth is not the center of the universe, but rather the Sun.
- This occurred around 300 BC.
- Prior to Aristarchus, philosophers like Philolaus and Hicetas had also entertained the idea of Earth moving around a "central fire".
- However, the idea did not gain much traction or development at the time and was further developed many centuries later.