Bright single white solid light/orb quietly flies across city sky at low altitude and extinguishes itself after passing over airplane.I am an avid sky watcher, and On Monday October the 22nd 2012, in Toronto, Ontario Canada, I was looking to see if I could see any satellites with my bare eyes. At 7:32 PM a low flying and bright solid orb-like light which was completely silent, and seemingly intelligently controlled, as it flew on a steady path at the altitude of the commercial planes which were in the sky at the time ( there were several planes for comparison, and they all had different colored blinking lights).The light was very brightly glowing solid white, and almost seemed to have a light blue tint or hue to it, much like a star. It did not change in altitude or brightness. It did not flash or flicker, or make a sound.This light was slow moving and did not appear to be attached any craft, but instead seemed to be the craft in its entirety. It traveled from the South West across the city toward the North Eastern sky, at which point a small plane flew directly under the orb/light. After they cross paths the light dimmed itself quickly and it appeared to disappear. It did not reappear in my view.