Planetary Bodies

About

There is a square world with 9 bodies representing the bodies in our solar system. Each body has a color representing the planet in our solar system. Each body will initially be a scale distance away from the middle body. Each body is also assigned a value for its real-life mass. Only The Sun, Mercury, Venus, Earth, and Mars are shown in the world but the rest are still drawn; you just can’t see them. The planets are their proportional distance from the sun but aren’t their proportional size. The point X=0, Y=0 is the middle of the world and the planets are aligned on the x-axis and have velocity in the negative y-direction. When the model is played or stepped or played the bodies other than the Sun move according to their velocity and the gravity of the other bodies. There are checkboxes to toggle on or off the different bodies in the model, which only comes into effect after the model is reset. There are also checkboxes to toggle on and off the planet's gravities which also only comes into effect after the model is reset. Additionally, there is a checkbox to toggle the bodies’ trails

Questions and Hypothesis

How long does it take an object to complete an orbit around a central mass?

Depending on that object’s mass, as well as the central object’s mass, the time varies. The bigger the mass is, the longer it takes for it to complete an orbit.

Which planet has the largest effect on the movement of the Sun?

Jupiter, because it has the largest mass.

Results and Behaviors

The results were that when there was a greater mass in the planetary body, and when it was farther away from the sun, the planet took a longer time completing a full orbit around the sun. Another behavior is that the planets depend on the sun for orbiting. This means that without the Sun, the planets will not be gravitationally pulled by any body and will move in one direction forever. This can be shown in the model when you uncheck the Sun box and press reset. Afterward, when play is pressed once again, the planets will not orbit like normal, and instead, will go up in a straight line for eternity.

These behaviors matched our expectations, because like in real-life, all planets and bodies in the solar system depend on the Sun to complete full orbits because of the gravitational pull of the Sun. Without the Sun, there would likely be no life on Earth, or any planet for that matter. All in all, this model mostly taught us about how all of the planetary bodies are tied together because of the importance of the gravitational pull of the Sun.

The results of this model did support our initial hypothesis that bodies with a larger mass would take a longer time orbiting the Sun. This is shown on our model, where Mars, the heaviest planetary body in the canvas, takes the longest time to complete a full orbit compared to the smaller planets of Mercury, Venus and Earth. Another way how the results supported our initial hypothesis of Jupiter being the biggest influence on the movement of the Sun, is when you uncheck Jupiter from the Toggle Planets list and reset the model, the sun does not move toward Jupiter (as it is not there) and instead, moves toward the next biggest body that is Saturn.

Reality Check and What We Learned

Some of the main changes we made to the model was including the gravity of the planets and not just the Sun. This allowed the model to depict how the solar system worked in real-life, and how the Sun moves in relation to the orbiting bodies around it. In addition, we made some minor changes to the design, such as adding a dark blue background to imitate the color of space, and changed the colors of the planets so they could be told apart from one another.

One of the main things we learned from doing this project is how each of the planetary bodies in our Solar System, particularly the Sun and the rest of the Planets, influence each others' movements, because of the gravitational pull between them. Specific to coding, we learned how to integrate research information such as the force of gravity into JavaScript so the model could mostly show how the planets move in real-life.

Sources

NASA Planetary Fact Sheet
Equation for the Force of Gravitational Attraction between 2 Objects