ABSTRACT
Many of Galileo Galilei’s (1564-1642) colleagues at the University of Padua in the Republic of Venice believed that the earth is standing still, not rotating on its own axis. Galileo could not accept this view. In an effort to convince Galileo, his colleagues argued that if the earth were rotating on its axis, a rock dropped from a tower would not land directly at the foot of the tower. They reasoned that if the earth were rotating, the tower would continue to move while the rock was falling through the air, with the result that the rock would hit the ground far away from the tower’s foot. Because this obviously doesn’t happen – the dropped rock actually lands directly at the tower’s foot – the colleagues concluded that the tower and the earth could not be moving. The colleagues saw no reason to change their belief that the earth and the tower connected to it are standing still.
