When I was a kid in Colorado some of us kids were out after dark. There was a crescent moon up overhead. As we played someone noticed a full moon... in addition to the crescent moon, and getting larger than the real moon. It stopped expanding and just glowed there for a minute or two, then rapidly shrank until it disappeared. One of the kids moms was a police officer, so she called her. They had other calls reporting the same thing, but we never received an explanation.