The movement of the planets and other celestial bodies in the Solar System is caused by

1. waves of solar radiation moving away from the Sun.

2. the repulsion of neighboring planets in the Solar System.

3. the sun's gravitational force

4. the pull from the edges of the Solar System

3. The sun's gravitational force.

The movement of the planets and other celestial bodies in the solar system is actually caused by the sun's gravitational pull or force.

Just like the moon orbits the earth because of the gravitational pull by the earth so does gravitational pull by the sun causes planets' and other celestial bodies' orbit.