I believe you.
1980, I was helping my son check his "trap line" in northeast Wyo.
We witnessed something very similar to what you saw.
I am not one given to hysterics, "tin foil", or paranoia.
But I saw what I saw.
It seems to me that it is the heighth of arrogance to believe that "we" are the only intelligent beings in the solar system.
There were also some "unexplained" cattle mutilations in our area around the same time frame.
That's another story.
So you know that I have minus zip to gain by standing tall on this one topic at least. I do apprecciate your support.
Actually, there are quite a lot of FREEPERS with first hand experiences. Some even with jobs around such.
But I hear mostly of such by FREEPMAIL and then even sometimes 2nd and 3rd hand.
My wife and I were crossing the high desert in SW Wyoming just last week and saw something strange. I should preface this by saying we are both licensed pilots, and I personally have been an avid pilot for more than 25 years flying everything from hang gliders to sailplanes, single engine and light twins with about 4000 hours accumulated airtime. This thing was gray, the shape of a hot air balloon, but about twice the size of a "normal" balloon, and was moving at jet speed about 500' off the ground. It passed between us and a small ridgeline that I would say was 1-2 miles to our north, giving me a pretty good reference as to the size. We talked about it all the way home. Balloons don't move like this, it could have been a powered parachute, but it was moving way too fast and it was pretty windy that day, probably too windy for a power 'chute. It was not a helecopter either. It flew in a semi-circular pattern starting in front of us and curving around as it passed. This was in the middle of the day in broad daylight, clear conditions, and what I would consider unlimited visibility. Neither of us have a clue as to what it was, but I sure would like to know....