I was out walking with my girlfriend and her dog tonight in O'Fallon Missouri. The sky was cloudless, with nice star viewing. I was looking up at the stars while she was watching the dog doing what dogs do when I noticed an object moving through the night sky at approx 11:40PM (plus or minus 15 minutes), Saturday November 9th. I first noticed it because it was blocking out the stars as it moved. The object was completely unlit, and was quite dark - although not as dark as the blackness of the sky itself. I could clearly make out its boomerang V shape as it passed above me, since it was slightly lighter than the background. It was not easy to see, extremely subtle, and would be easily missed. It was silent. It moved at the same speed and in the same unwavering direction the entire time I watched it. I was able to track it for less than one minute. It moved from roughly north to south across the sky, and was nearly directly overhead as it passed me. Its course would have been roughly parallel to Highway K in O'Fallon, MO, the nearest large road to my viewing location.I did not get a chance to view its entire course across the sky, I first noticed it perhaps halfway up from the horizon as it approached me and then lost it in a similar position as it passed into the distance. As it crossed over me it's "apparent size" from my location was very similar to holding one of the 2 or 3 inch matchbox type airplanes out at arms length above me. Due to the way it blended in so very well with the night sky I lost it from my sight well before it reached the horizon. It was impossible for me to tell how big it was or how high due to a lack of scale reference to it. When I first noticed it I thought it was a large bird or owl hovering in the sky hunting, however that impression did not last. As it approached closer I thought perhaps it was a kite or odd shaped balloon floating slowly by. None of these impressions lasted more than a few seconds though. It was clear well before it was overhead though that it was neither an animal nor an object floating in the wind. The object was a squared off "V" shaped aerial machine. The angle of the "V" was wide, perhaps as much as 120 degrees. It was a narrow, if you want an approx of its appearance/shape/scale then imagine two black 12 inch rulers pinned together at a wide angle. I commented something like "what the $#$%@! is that?!" after looking at it a few seconds, and continued to verbally express my incomprehension of what this object was. I pointed it out to my girlfriend but she could not locate it in the sky. The closest aerial vehicle that I know in comparison to what I saw would be the Northrop B2 bomber, which are stationed in central Missouri, and I have seen them in flight before. However, given the actual size of a B2 vs the relative size of the object I saw, the engine noise would have been extreme. Also the object I saw did not have an apparent engine section extension added to the "boomerang" body shape, like the B2 has.