Studying vector calculus tends to make you see space curves everywhere you go. Here’s a conical helix (or a helical cone?).
A good way to understand the behavior of curves in space is to understand how their projections behave. The sun does a nice job of showing us one such projection of this space curve.
This suggests a common mathematical practice: trading a hard problem for an easier one. Space curves can be difficult to analyze, but their projections are more easily understood. And by understanding its projections, you can develop knowledge of the space curve itself.
Of course, it’s important to understand what information you lose through the projection, as well!