Interstate 80, westbound, Wyoming, flying object seen by police officer and familyI am a police officer in the state if Illinois. My family were on a road trip to Utah in September of 2005. On Interstate 80 in Wyoming, driving through miles of farm or pasture lands, on the 27th or 28th in the late afternoon, I noticed jet streams from aircraft at extremely high altitudes. This is normal and did not concern me. But as I looked occasionally due to bordom of the drive, I slammed on my brakes due to a fear that "something" may have fallen off one of these air planes and was about to hit the roadway. As I kept my focus on the object, I drove very slowly, realizing that it was not falling. I guestimate the object was approximatly 300-600 yds above ground. It was almost directly overhead. It was difficult to make out shape due to what I first believed was a very strong reflection of sunlight comming off the matalic surface of the object. It had a compact form, and I believe it to be a spherical shaped object. It did not have wings, strobes, lights, or propellers. It was still day light. My wife asked why it was so brite. I told her it might be a weather baloon and it was reflected sunlight. My wife said,"No! We're driving west, the sun is over there (in the direction of our travel), it can't be reflecting the sun." I became nervous at the relization that she was correct. Then the object turned dark. This was as strange as the brightness. It did not just turn off the light, it became a black sphere in the sky floating above our car. Then it took off. I have never seen anything move that fast in my life. It traveled west and was no longer visible within seconds. As we calmed our children down we tried to rationalize what we had seen. About 5-10 minutes later, my wife yells "there it is." Just as before, above us, slightly in front, extremly close. Again, it turned black, and took off. I took the next exit and waited. Hoping (sort of) that it would appear again (may possibly be three seperate objects, or same one that "circled back" with out us seeing it). As my wife looked for the camera, it did appear again, but this time it turned to black much faster and, again, took off in the same direction. Based on size above our heads, and when it visually was no longer visible as it travelled, I guestimate it travelled over at least 100 miles within seconds. No trail, no sound.((NUFORC Note: Witness indicates that the date of the event is approximate. PD))