Most planets in our Solar System have moons – Mercury and Venus are the exceptions. The moons and the planets stay together as they travel around the Sun.
Related resources:
- Natural satellites – article
- Gravity keeps satellites in orbit – video
Transcript
To demonstrate the orbit of a moon around a planet as they both orbit the Sun, roll a small and a large marble around a large central mass.
The large marble will distort the sheet close to it enough to hold the small marble close as they both make their trip around the large central mass.