An unknown shaped object about the size of a locomotive engine moving at very high speeds without lights. It was "hugging" the highway and only approx 200 feet off the ground. It was westbound on I-70 in Utah west of the eastern border with Colorado at about 2300 hrs. The object then returned a few minutes later and was eastbound in the same manner.

I am not sure if it was only one object passing us and then returning or two seperate objects.  When the object flew over our car and down the highway ahead of us, it was almost surreal.  I wasn't sure what I had seen.  I asked my wife "Did you see that?"  Her reply was she wasn't sure what she had seen.  A few minutes down the road (westbound) it came back at us (eastbound).  Only about 200 feet off the ground and without any lights.  That part of Utah is mountainous and not well lit.  There was a mild snow shower occurring which also impaired clear view.  The object made no noise and there wasn't any kind of wind blast or anything that should be associated with an object of it's size and so low to the ground moving at such a speed.  If I had to say what shape I believed the object to be, I would say triangular or at least multi-angular.  Not long after that, the F117 Stealth fighter became public and I remember thinking that the shape of the object we saw could be described as similar.  But I was in the Air Force, working on the SR-71 program.  I am very familiar with U.S. aircraft and even some of the "black" programs being that I was in aviaton and worked on a program of secrecy.  This was not an aircraft that I then or now have been familiarized with.  When the object made it's second pass, I said to my wife "Now don't tell me you didn't see it that time..."  Her reply was "I don't know what that was and I don't want to talk about it."  You must understand that my wife was raised in a family that was and is still very devout Christians.  Her father was a Pastor of a church most of his life and now teaches at a Chrisitan college.  I too believe that Jesus Christ is the savior of mankind.  But in conflict with or maybe just not congruent with my beliefs is this experience.  I am not ready to jump up and say that this was some sort of alien craft, all that I do know is that it was something that I cannot explain and that even with the experiences I have had in dealing with aircraft and "black" progra! ms, this event is still beyond my understanding.