Johannes Hevelius FRS, Selenographia (Danzig, 1647)
Hevelius (1611-1687) was an astronomer in Danzig (now Gdansk, Poland). He was the first to publish very detailed images of the Moon's surface, showing craters, shadows and lunar mountains. Until Galileo's observations earlier in the 17th century, people had believed the Moon was a perfectly smooth sphere, not subject to change or decay. These new images of its rough surface prompted scientists to ask how the Moon was made, and to question the worldview of the ancient Greek philosophers.