Single saucer shaped craft observed from Duluth, MN, skies over Lake Superior-first stationary, then NW movement.

When I was ten or eleven years old, 1958 or 59, I lived in Duluth Minnesota.  We lived on a hill about 10 miles from Lake Superior.  
One night in the beginning of fall September or October I were going to bed.  It was around eight thirty or nine o clock when I happened to look out my bedroom window when I noticed a bright light that sat over the lake for a long time, maybe ten minutes or so and then it moved towards our house but in a north westerly direction.  It had moved very fast and then stopped again for about five minutes.
It was like a white when I first saw it but after it moved, it now had red, green, and white flashing lights.  After a few minutes it suddenly disappeared totally!  I don’t know exactly what it was but years later; I came to believe it was a flying saucer.  I told my mother about it and she said it probably was an airplane, but back in those days, airplanes didn’t hover.
Witness indicates that the date of the sighting is approximate.  PD