1. The planet orbits are slightly squashed circles (ellipses).
Comets have special orbits which mean they are much closer to the Sun at some times than at others.
The further away the orbiting body, the longer it takes to complete the orbit.
Orbits

2. Planets orbiting
Planets orbiting

3. Comets
Comets

4. Gravity is an attractive force which acts between all objects.
Gravitational force increases with;
increasing mass of the body
decreasing distance from the body
Planets and satellites can stay in orbit because they are travelling above a certain horizontal speed
Gravity

5. Gravity
Gravity

6. Geostationary Satellites

7. Monitoring Satellites

8. Quiz
Quiz