A UFO?

Okay my Mother has had an experience awhile back in '79 in Princeton, New Jersey that she thinks may have been a UFO sighting, but she isn't sure. On the opposite side, if anybody has any knowledge of possible experimental aircraft similar to the following discription, I'd like to have that too if you could.

She says she was driving with her friends down a street wooded area, it was at night, and slightly cloudy. her friend began saying "look, up there" and she looked up, and there was something in the clouds, like a repeating, large flashing white lighting, similar to lightning, only just above the clouds. Something came down from the sky, from her angle, it was circular and disc shaped, and was big, about atleast 140 feet in diameter (from one side to the other). all around its edges were colorful lights, all blinking and shining, but her memory is fuzzy on what colors were there and how it was moving. It began moving in the sky slowly in a straight line, eventually going out of view over the trees.

Anybody know if this is a UFO? or maybe was it an experimental craft? It had: Multi-colored lights around it, 140 feet in diameter, a disc shape. It was in 1978-79 in New Jersey (near princeton.)

The last time disk-shaped aircraft are known publically to have been tested or researched was in Nazi Germany. Disk-shaped aircraft are highly inefficient and I am not even sure a 140-foot wide craft such as this is in accordance with standard laws of physics as something that is capable of flight in such a manner. Technically it is a UFO if you can't identify it, and so it was in the first place. I would say that it is indeed anomolous and worth reporting to www.nuforc.com...