low flying disc, flew right over us

We were heading south on rte 236 from S.B. at dusk when we noticed a slow low flying disc shaped craft heading west over what is now known as the Marshwood Great works School I pulled my vehicle over to watch it as it crossed 236 when we couldn't see it anymore I turned right on the rd on the west side of 236 to see if we could find it that's when we noticed to our left the the craft was heading north straight at us just barely over the tree tops approx. 75 ft in the air and traveling at a very slow speed approx 10 mph, I got out and stood as the object past directly over us, so I got a real good look at it the craft was making no noise what so ever, it was approx. 100 ft wide with bright white window like lights going all around the outside center of the craft and on the bottom center were bright white lights approx 25 ft in diameter in a circle, after it went over us it went straight up fast heading toward S.B. when it got to about where the Salmon Falls r! iver is it stopped and dropped straight down and disappeared.  This happened approx 24 years ago when my son was about 10, it's a day I'll never forget.