Galileo's Sighting of Neptune
He first observed it in 1612 and thought it was a fixed star, some 234 years before it was discovered to be a planet. His data cast doubt on the accuracy of modern orbital calculations for Neptune
Newton's Apple and Galileo's Dialogue
Newton did see the apple fall, but what was it that inspired him to link the apple's descent to the moon in orbit and arrive at the law of universal gravitation? It may have been a diagram in the "Dialogue"
Galileo and the First Mechanical Computing Device
It was the sector, which could be employed to solve mechanically a number of mathematical problems. Galileo devised it to attack an insoluble problem and then perceived its value for simpler ones
The Role of Music in Galileo's Experiments
A hitherto unpublished page of Galileo's working notes, preserved in Florence, implies a remarkably simple scheme for equalizing short time intervals. The secret of his success, it now appears, was a song
Galileo's Discovery of the Parabolic Trajectory
He showed that a body falling with a horizontal component of motion describes a parabola. It has been thought that he did so solely by principle, but it now appears that he conducted careful experiments
Galileo's Discovery of the Law of Free Fall
It has been thought that he erroneously assumed that the velocities of a falling body were proportional to distances. A new manuscript shows that he treated them correctly as being proportional to time