The ancient Greek astronomer Aristarchus of Samos (c. 310 – c. 230 BC) is credited with being the first to attempt to measure the relative distances from the Earth to the Moon and the Sun. He did this by observing the phases of the Moon and using geometry to calculate the distances.

While his method was not entirely accurate, it was a groundbreaking attempt to understand the scale of the solar system. His work paved the way for later astronomers to refine these measurements using more sophisticated methods.