The apartment building I live in is non-smoking. I go outside, quite often at night,to smoke. Tonight, the weather was nice, so I took a chair with me and sat outside for awhile with my fiance and a neighbor. As we were talking, I leaned my head back to look at the stars. I took notice of one that seemed to be moving, and learned that it actually was. A very steady pace, seemingly too fast to be an airplane. I heard no sound to accompany it. I watched as it traveled on a straight path, roughly heading north-west. I lost sight of it as my neighbor noticed another one moving west. This one I never caught sight of, however, another one caught my attention moving south. I followed this one until it got overhead and vanished from sight. I assume it left the atmosphere. I kept watching the skies for signs of more, and sure enough, another one came from the north heading in a south-east direction, however, this one seemed almost to have a snake-like flight path. I watched this one until I couldn't see it, any longer. My neighbor and I stopped watching skyward and began discussing what we witnessed and eventually we all returned, indoors. This began around 11:20 p.m. and we came inside around 11:45 p.m. After eating a small snack, I went back outside at about 12:10 a.m. for another cigarette, and 3 of my other neighbors were outside. I told them about the earlier sighting and, as we talked, I looked up just to see if there might be more. Sure enough, a fifth one was there, and I pointed it out. 2 of the 3 that were out there were able to see it. They agreed it was too high up to be an airplane. On top of this observation, I don't believe there would be 5 separate airplanes in the same area of sky within an hour. They were so high up, they looked like faint star light, yet you could easily tell they were moving.