Space is big, really big, even if it looks small. I doubt you would be able to block enough but that is just armchair guessing. Things like reemission might also help?
“Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.”
— Douglas Adams
I hope this quote has made its way into the academic literature in some way.