# Solar Motion Simulator

## Introduction

This printable model helps students see the relationships between the Sun's position in the sky, the time of year, the time of day, and their latitude. These relationships, while simple in principle, are abstract and are often difficult for students to visualize and understand deeply. I struggled to teach this the first time I taught an introductory astronomy course in the spring of 2021. Although it can be very useful and effective for students to see a demonstration in class, such demonstrations can be easily forgotten, and they do not help students who miss a day. I wanted to give my students something they could take home and play with.

My middle school science teacher used a paper model to explain the motions of the Sun in the sky. That helped me understand these abstract concepts very well, and I wanted to do something similar for my own students. I spent hours online searching for this model, to no avail!

Finally, I decided to design one myself, inspired by that foggy memory from middle school. I wanted this model to be cheap, easy to make, intuitive and interactive. I sketched an initial design on paper and then developed it iteratively over half a year using LaTeX and TikZ.

A very big thank-you goes to Turner Howard (also UWEC) for giving me numerous suggestions and assistance with developing the laser cutter diagram!

## Video Tutorial

I am working on a series of video tutorials that show how to assemble and use the model. The playlist is shown below. (Note: videos with assembly instructions and more examples will be added soon!)

The model that inspired this work was almost certainly the Solar Motion Demonstrator developed by Joseph L. Snider of Oberlin College (which I only found online on 1 August 2021!). Snider's model is simpler to construct, making it well-suited to public demonstrations or middle school classrooms. My model is more complicated to construct, but it has a base that lets it stand on its own and comes with assembly instructions. My model is also more detailed: there are more angle markings throughout, a key for the solstice and equinox dates, and a clock on the bottom for helping read times. Finally, my model also includes a laser cut diagram which allows instructors with access to a laser cutter to cut out the shape in such a way as to leave the parts in the paper, ready to be punched out by students. This allows for easier distribution in class and can save significant assembly time in class.

## Using the Solar Motion Simulator

Although I was developing this model primarily for my own students, I designed it for broader distribution as well. I want this model to be widely and freely available to help spread the understanding of and love for astronomy.

If you would like to use it, you can download any of the three files below. If you do use them, I would LOVE to hear from you! I would be especially grateful to hear your suggestions and how you used it.

### Supplies Needed

• Thick paper (a thick cardstock is best)
• Scissors (or a laser cutter!)
• Clear tape

### Variations

I have made a version that includes just the pages to be printed and another with a page of instructions. I have also included another PDF that includes red lines for laser cutting. I suggest printing the two-page PDF on a thick cardstock and either 1) laser-cutting it and then punching it out, or 2) cutting it out carefully using scissors. I encourage you to use professional printing services to print these, as the printing alignment between the front and back sides of the paper is important.