I was staring up at the stars around 11:30 PM and noticed an object moving. It had no lights, and was not bright whatsoever. It was moving smoothly and in a straight line, except extremely fast, and dead silent. It was fairly large too, compared to how big stars look. Never would have noticed it had I not been looking at that particular region of the sky at the exact moment I did. It had to have crossed the sky in less than a minute. In fact, I feel like I've seen this same kind of thing once or twice before.
My question is what did I see? The fact that it was extremely dim, extremely fast, and produced no sound really confuse me.