Approximately 4.6 billion years ago a large cloud of gas and dust was disturbed by some force. As a result of this disturbance and the energy introduced to the cloud, the cloud began to move. Once the movement began, the cloud started to collapse in on itself due to its own gravity.
A solar system is a star and all of the objects that travel around it are planets, moons, asteroids, comets and meteoroids. The solar system extends much farther than the eight planets that orbit the sun. Scientists estimate that the edge of the solar system is about 9 billion miles from the sun.