An orrery is a mechanical model of the solar system that demonstrates how the planets move in orbit around the Sun. The orrery was likely invented by George Graham in 1713 who presented it to Charles Boyle, 4th Earl of Orrery.
The planets orbit around the sun in an elliptical motion, kind of like moving on the edge of an oval. To model these planets, astronomers measured physical values and found the Keplerian parameters. These parameters are shown in the diagram above.
These Keplerian parameters can be used to calculate orbital propagation, or the orbit position through time of the celestial bodies. A resource on how to do the calculations can be found here: https://ssd.jpl.nasa.gov/planets/approx_pos.html
First, click the Play button to view the model. Use your mouse’s scroll wheel to zoom in and out (or two finger commands on Mac) and click and drag to change the viewing angle. To use the controls, click the down arrow. You will find a slider that controls the speed of the simulation and how fast the bodies are orbiting the Sun.
The model was developed using HTML, CSS, and Javascript, languages that make up the basis of the internet! The threejs library was used to create the graphics and control the camera. It also incorporates bootstrap components to make the navigation bar.