When it looked like the comet ISON had the potential to light up the night sky in late 2013, we immediately set out to see if it would be possible to track its progress and trajectory directly on TIME.com. This posed a small technical challenge since the universe has three spatial dimensions, while TIME.com only has two. This means we had to choose an angle from which to view the solar system and project it onto the screen.

Thanks to great instructional material from the Jet Propulsion Laboratory, we were able to take the galactic position of each planet and comet in their database and visualize it dynamically by date. The math can get a bit hairy here, so we’ve published the code for finding the position any planet or comet at and point in time and translate it to a point on your canvas. As a bonus, because the functions take the angle at which you’re viewing the solar system as an input, you can simulate 3D behavior by allowing users to manipulate this variable.