I was more surprised than I can say. Because I teach physics, I have a better feel than most for
- the real distance between stars,
- how hard it would be to travel from one star to another, and
- how unlikely it would be for any creature to travel from one star to another and behave the way the crews of flying saucers are said to behave.
While all this was going through my mind, the saucer appeared to be slowly coming closer, and gradually I became aware of a low, buzzing sound. And then, suddenly, I saw exactly what it was, and the flying object ceased to be unidentified.
It was a powered paraglider. The canopy was illuminated just for show, and in the twilight the pilot and paramotor were not visible until they were quite close.
Before I get all kinds of angry comments: No, of course I am not saying all UFO's are powered parasails. On the other hand, I remain convinced that they are not space ships from other planets, either. In any event, if I had not stayed to watch or if the "saucer" had not come my direction, this easily could have become yet another sighting by a "credible witness".