I've been an astronomer for 40+ years. Have seen a few unexplainable things at night ,and also managed to capture one fast moving light in the daytime. One Sunday afternoon in February 2007. In the back garden in Coventry UK ,with my new Canon dslr + 105mm lens in my hand, set up with fast shutter,infinity-focused...and within 10 minutes suddenly saw a bright light flying level with the north horizon,from east to west. Much faster than any low-level nearby fighter plane I have seen before. Probably too slow for a meteor however.Totally silent.Maybe 30 degrees elevation. Just about had time to bring my camera to my eye ,and fire off a burst of 3 frames. Ecstatic to find the object on one frame.
Image is a crop from the original 10mp raw .Shows a tiny yellowish-white light . I cannot stress enough how fast this thing was . Crossed most of the northern sky in less than 5 seconds.
I sent the image to well-known astronomy author Ian Ridpath, who rules out a meteor, and said it *could* be a helicopter. I would say no chance.
Cheers,Phil