The Solar System

Below is a simulation of the Solar System of all the eight planets rotating around the Sun in a 2D plane. There is an adjustable speed for the rotation of the first four planets, and for the all the planets. This is because if you rotate all the planets, the last three planets: Saturn, Uranus, and Neptune, take a long time to make a single rotation, whereas the first four to five planets make relatively fast rotations. Note: The distance between the planets, and the size of the planets in the simulation are not to scale. The revolutions however of the planets within the simulation are relevant.

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One thing you might notice is that the last three planets take a relatively long time to make one revolution around the Sun, whereas the first four to five planets take a relatively shorter time to make revolutions around the Sun. This is because of Newton's Law for Universal Gravitation.

The distances between the planets and the Sun significantly increase as the planets start to move farther away from the Sun. The sizes of the planets, for the most part, also start to increase significantly as they move farther way from the Sun. Due to the large distances of the planets from the Sun and their sizes, this causes the planets that have a smaller distance away from the Sun to move faster as the Sun and the planets close to it possess a larger force of attraction. The planets that are farther away from the Sun also experience a force of attraction, however since they are farther away, the force of attraction is weaker compared to the stronger force expereinced by the planets close to the Sun.

You can also notice that there is a form of centripetal acceleration that the planets experience as they rotate about the Sun. In the simulation, the paths of the planets around the Sun is circular. Realistically the planets in our Solar System follow an elliptical path, but the elliptical path is so small, that if inputted into the simulation, it would still look like a uniform circle. Hence it is worth noting that planets move in an ellipse that is almost circular. Due to this almost circular orbital motion, it can be understood that planets experience centripetal motion as the center of our galaxy, the Milky Way is the Sun, and as that is our planetary point of origin, it makes sense that the planets follow centripetal motion, as they are moving in an elliptical path with constant speed.

Now you can see how distance, and planet size plays a role in the Gravitational Force of planets, and how the Centripetal Force acts on planets as the Sun is the center of our planetary system.

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