While researching a topic, a student has taken the following notes:
- Saturn has 146 moons, including Hyperion and Prometheus.
- Hyperion completes an orbit of Saturn in 21.28 Earth days on average.
- Prometheus completes an orbit of Saturn in 0.61 Earth days on average.
- German mathematician and astronomer Johannes Kepler (1571–1630) described the orbits of planets as elliptical in shape rather than circular.
- Kepler published three laws of planetary motion to describe the orbits of planets around the Sun.
- Kepler’s laws also apply to the elliptical orbits of natural satellites (e.g., moons).