disc disappeared traveling north on hwy 491 near Yellow Jacket, CO, I noticed a small object in the sky that I immediately decided it was an object unknown to me. This area has a lot of small airplanes fly over us and commercial jets. Checking one second on it and another on traffic, (I was driving), it came towards me becoming a larger object. It was very fast to cover the area from first seeing it to when I last saw it, maybe 20- 30 seconds or less. It stopped before it got to the hwy. It was a disc with a dome on top. when I looked a couple of seconds later, it was gone. Awesome.