UFO's in Yellowstone???

Part of me wants to think there are UFOs. The other part of me says there are no such thing as UFOs. But, I think people are seeing something. The question is what are they saying. I think there is an explanation for everything we just don't understand it at the moment. After all UFO means unidentified flying object. Once it becomes identified it's no longer a UFO we just don't understand what we are seeing. I would enjoy the park and forget it.