Galileo's ship

Galileo's ship refers to two physics experiments, a thought experiment and an actual experiment, by Galileo Galilei, the 16th- and 17th-century physicist and astronomer. The experiments were created to argue the idea of a rotating Earth as opposed to a stationary Earth around which rotated the Sun, planets, and stars.

An argument that was used at the time was that if Earth were rotating, there would be detectable effects on the trajectories of projectiles or falling bodies.