So I just read this and I thought it was really interesting. I'll make it a puzzle:
Whenever I teach Roemer's method for finding the speed of light, I am always amazed that anyone in that era would time the orbits of Jupiter's moons so carefully. But know I know that the timing of those Moon's was a potentially important and relevant matter at that time for a reason unrelated to the speed of light but with potential for great economic and military implications...