I woke up at night and looked out the window near my bed. There was a huge sphere of shining light in front of our nine floor apartment block building, on the level of seventh or eighth floor. I observed it during approximately twenty minutes, to the best of my knowledge, and after that fell asleep. I was ten years old and decided that it was a contact with aliens. Nobody else has seen the sphere, although it's lightning ought to have been very noticeable. From that time on never did I experience the same.