Rob Woodus breaks down the Beaver, Utah UFO video and calculates the speed using math and distances in Google Earth. He presents some data that may help to rule out some other theories that have been presented.
He calculated that the UFO would have traveled two miles in one second at a speed of 7,200 mph. He then showed how fast an object would have been travelling if it had come from a closer location. In this case, he used the theory of this object being a bird and calculated the speed from a utility pole seen in the video. He calculated that a bird flying from the closer utility pole location would have traveled a quarter mile in one second at a speed of 900 mph.
More about the Beaver, Utah UFO sighting.