Unknown oval object illuminated silently, startling cattle and observers.On Friday, March 29th, at approximately 17:45, I observed an object that I firmly believe to be other than any conventional aircraft I am aware of. This event was witnessed by my sixteen year old son and my 14 year old daughter as well. I am a retired police officer who is not given to flights of fancy, so it is with careful thought that I bring this event to your attention. We were traveling west on Colorado 36, approximately four miles west of Last Chance, Co. when my son first noticed the object to the north of the hiway above a pasture. At first I thought it must be an aircraft either enroute to or departing Denver International Airport, approximately seventy miles to the west of our position. However, as I began to watch the object I could tell that it was not moving and that the distance between it and my vehicle was closing as I approached it. In about five minutes I was parallel to the object which was over a pasture approximately three hundred yards from the hiway. I stopped the car on the shoulder of the road to get a better look at the object, still thinking that there was an explanation such as weather balloon, helicopter, etc. It soon became apparent to me that it was not a balloon, as it was absolutely unmoving in a breeze that would have easily moved an inflated object (10 to 15 m.p.h. out of the northeast). It also was not a rotor craft. The object appeared to be slightly oval shape, with a "dull" metallic look to it. I turned the engine of the car off and there was absolutley no sound from the object. This is a very sparse farming and ranching community with very little traffic of noise pollution of any kind. The slight wind was in the direction to have brought any sound toward my vehicle. The object appeared to be 25 to 30 feet in diameter and close to 10 feet thick at it's midsection. There were cattle grazing in the pasture, not directly under the object, but only 100 yards or so to the east. They seemed to be completly unaware of it's presence. It was dusk and getting darker as we ! watched the object, still trying to decide what it might be. Another vehicle approached from the east and slowed as it passed us, an elderly couple who were obviously looking at the same thing we were. The vehicle declined to stop, but rather accelerated and proceeded west. My daughter began to get a little upset and asked if we could leave. I could tell she was frightened and when I looked to the back seat, she was looking away, choosing not to even look at it anymore. As I told her we were leaving, the object illuminated, again without a sound. I don't mean some lights came on around the perimiter or flood lights. I mean the entire object itself "glowed" an orange-red color. Even though there was no sound that I could hear, when the object lit up, the cattle suddenly bolted, all at once, in different directions. I've seen cattle shy from noise or threat before and they all turn to run from the percieved threat. These cattle were running into each other like they had no idea which way to go. At this point, I became concerned for our safety. I don't know why, the vehicle never moved or did anything of a threatening nature, I simply was afraid for my children and myself. The vehicle started without hesitation and I left heading west again towards Denver. My daughter was now crying and my son's initial excitement had also been replaced with a quiet uneasiness. I continued to watch the object as best I could as we left, but it was dark enough now to make it hard to see. The illumination had only lasted for maybe 2 or 3 seconds. My son caugh the last glimpse of the object as we crested a hill. It appeared to be in the same place as it had been.After talking with my wife and a few close friends, I decided to keep quiet about the sighting. I now regret that decision because it may have ben easier to find out who else migh have seen this if I had come forward earlier. In my profession people tend to discredit these types of subjects, as well as the individual making the report. If you have recieved any information regarding the incident my children an I had that evening, would you please advise me?((NUFORC Note: We spoke with this witness, and found him to be serious-minded and credible. PD))