Foo fighter

Well kiddo, during World War II, some pilots noticed some weird lights flying around their planes. They called these lights "foo fighters." They weren't sure what they were, but they didn't think they were good. The pilots thought they might be some kind of secret weapon the enemy was using. But, no one knows for sure what these lights were. Some people think they might have been natural phenomena like ball lightning, and others think they might have been aliens! But, whatever they were, they were definitely a mystery!