spinning disc present in back garden grass area, close to house.

as above.  i was a young boy awakened by the disturbance, looked out of my bedroom window and saw an object of the above description about eight feet or so in diameter on the grass.  in the morning there was a yellow circular mark on the grass where i had seen the shape.  i showed my father who is now deceased.  i have not reported this before. i am 43 years old, stable background.
Date is approximate.  PD