>"Bussard collectors" I think I read somewhere that despite this being a science fiction trope forever, there may not be a region between "too thin to produce

>"Bussard collectors" I think I read somewhere that despite this being a science fiction trope forever, there may not be a region between "too thin to produce net power" and "thick enough to blow up a spaceship at relativistic speeds". And in practice, the interstellar medium turned out to be the former, too thin. In fact, I'm not sure but what someone may have calculated drag would exceed power generated, regardless of density.