At the time, rockets were unheard of and the biggest problem was how they were to search for something they didn't know what it looked like. It's an ancient problem, posed two thousand years ago by Plato in the Meno dialogue.
Meno. And how will you enquire, Socrates, into that which you do not know? What will you put forth as the subject of enquiry? And if you find what you want, how will you ever know that this is the thing which you did not know?
tags: detection, problem, solution, scale