Tracking the international space station with an Arduino

Summary

Last summer I received the very fun HackPack for my birthday. Every 2 months you get a box of parts and assemble a fun hardware project. The first item in the pack was the IR turret. You control the turret with an IR remote, and can shoot the little foam bullets at things. It was pretty cool, but I’m not a huge fan of shooting things. At around the same time I saw this XKCD: I am into going outside to watch fun stuff happen outside, especially if it is when the International Space Station (ISS) is passing overhead. I also thought the XKCD device was a pretty fun idea. After chatting with my friend Trevor at Plateau Astro, I figured I could hack the IR turret into something that points at the ISS at all times. He pointed me to this awesome project, where someone had done something similar. What is the ISS As a quick refresher, the International Space Station is a big habitable space craft that orbits the earth at an altitude of about 420km. It travels at a speed of ~28,000 km/h, and completes an orbit roughly every 90 minutes. There are astronauts living on the ISS, where they conduct cool experiments, and get to do things like strap themselves to walls in order to not float away while they are sleeping. The best part about the ISS (for me), is that you can see it from earth! At night when it passes overhead, it looks like a very fast moving star, or a very very far away plane. You can download an app like ISS Detector, which will alert you to any visible passes. Once you get comfortable going out to look at the ISS, you can also start doing silly things like bouncing radio signals off it, or talking to the astronauts on board. Building the ISS tracker For motivation, here is the final product as the ISS passes directly over my house: Your browser does not support the video tag. Pointing at the ISS Our goal is to point an arrow at the ISS (without looking at a phone), so we know when it is above the horizon so we can see it. Given the design of the IR turret, we’ll n...