I saw this light in the sky and initially thought it was an airplane spraying for mosquitos. I then realized the pattern was erratic and not in a straight line, there wasn't a red light, but just a bluish/white light that pulsed, not strobed. Sometimes it went out for several seconds. The lighting was not consistent with commercial aviation. Also the flight pattern varied from similar to a helicopter to an erratic jumping around to faster than a jet. I drove half a mile still watching it. I found a security guard on a parking lot and asked him to turn around. When he turned, and I don't think it was because he turned, it speed off faster than anything I've ever seen and was out of sight in less than five seconds, off the horizon. When it left the pulse of the light increased. I did not hear a sound, but there was other road traffic in the area. I have learned to delete unnecessary data from my phone. The short clip would have been six to ten seconds longer and showed the objects departure if I would have had more memory.