I was driving into Sedona to work on route 179 at approximately 7:45am. Shortly before the Villlage of Oak Creek my 10 year old son who was in the back seat said "What is that thing in the sky?". I said it was probably a plane but he seemed insistent so I strained my neck to look where he was pointing. At that time I noticed what appeared to be a shiny metallic-like object that seemed to be halfway between a round and disc shape. It was high in the sky, about where a small plane would normally fly. It was not moving, just hovering. As the road I was on is very winding I couldn't keep my eyes on it for very long at a time. My son, however continued to observe it for at least 4 minutes. It didn't appear to do anything except hover high above the rocks until I looked up the last time. Then it appeared to get physically smaller and smaller over a period of about 15 seconds until it completely disappeared. Shortly after this I stopped in the Village of Oak Creek to get a coffee, all the while marveling with my son over what we had just seen. After about 5 minutes we proceeded to get back on the road at which time my son said "There is is again". It had moved position slightly and seemed a bit lower this time. A jet plane flew almost directly over it at that time and it gave us a bit of perspective as to the size. It seemed to be about a quarter of the size of a large plane. Once again, it just hovered and did not make any movements. (or sound that we could tell) We continued to watch it for another 3 or 4 minutes (myself in between looking at the road of course)and because of the enormous rocks and cliffs around Sedona we then lost sight of it. UFO sightings around Sedona are known to be a bit "common". I have personally seen many "strange" lights in the night sky but have never seen anything during the day. I am a professional singer in Phoenix but I also work at a mortgage company in Sedona during the week.