Previously, we looked at Newton’s law of gravitation and how it provides an explanation for the motion of falling objects near Earth’s surface, the motion of the Moon and satellites around Earth, and ...Previously, we looked at Newton’s law of gravitation and how it provides an explanation for the motion of falling objects near Earth’s surface, the motion of the Moon and satellites around Earth, and the motion of the planets around the Sun. In this chapter we step up in scale, applying the law of gravity to the motions of stars and gas in galaxies and galaxy clusters. These larger-scale gravitational studies began early in the 20th century and continue to the present.
