Very large dual disk saucer ,counter rotating hovering and finally submerging into lake superior about 1/2 mile offshore.

As I was traveling toward Marquette mi from Harvey mi On 8/18/19883  on US41 I noticed a odd object in the sky on the left  side of the car I was in .
The object was stationary and hovering it was very large Over 500 feet across it was a dual disk that slowly counter rotated  as it hovered Tilted with the bottom toward me  about 15 degrees So as to allow the landing legs  to be quite easily made out .
The dual disks had lights  on the edges and large lighted windows that had bay like projections .
Also the narrow mid section did not turn and there was a bit of a dome at the top of the upper disk with a row of lights .
Lights were many colors very bright red ,green yellow and white .  The object  was visible As I was traveling  toward Marquette  the object  hovered for a few minutes and then went over the road and out over lake superior and slowly went under water after it got about 1/2 mile out it was very cool and a bit odd I personally prefer my special effects on tv or the movies this was the only time I have ever seen  such a strange object  it was many years ago but I could still sculpt or draw  a model even to this day