She described an object ''about three- quarters the size of my house, with an L-shaped structure suspended underneath it.''

''It actually stopped over the house,'' Mrs. Lunn said. ''At one point, all the lights went green, then red, then they went back to a pattern of green and red and white. I felt like it was letting us know it knew we were watching it. That was scary. It went on for about 10 minutes.''

The state and local police are flooded with calls every time the objects are seen. Many of the sightings have been reported by police officers on patrol.

One officer, according to Sgt. Kenneth V. Spiro of Troop K of the state police, which is responsible for the area in which sightings have been, followed the object.

''He tracked it to Stormville airport,'' the sergeant said. ''It was a group of light planes. They fly in formation. The undersides and under the wings are painted black, so they can't be seen from the ground. The planes are rigged with bright lights that they can turn from one color to another. It's the lights that give the shape to the U.F.O.

''The trooper spoke to a couple of the pilots, and they're getting a big kick out of it. There's no violation of the law here.'' He refused to give the name of the trooper or of the pilots the trooper spoke to. The airport, a small field in Dutchess County, was deserted the other evening. Neighbors said they had seen no activity on recent nights.

But for many people, questions remain. Some wondered how airplanes could hover over an object or how they could shoot straight up into the air. Others said that they had seen the hoaxers but that they had also seen something different.