Encircled by an UFO? The weird encounter of Captain Júlio Miguel Guerra

Following my own demarcations about the nature of a strange flying object having been sighted, I see a UFO as any object in the air which cannot be accounted for with our current knowledge. It stands to reason this isn’t necessarily the same thing as an alien spacecraft.
Given this definition, the general claim that UFOs really exist isn’t extraordinary by any means and seems almost certain to anyone having taken a look at the most puzzling sightings with an open eye.
Yet one can still find hardcore skeptics such as German debunker Werner Walter confidently asserting that there are “no unsolved cases“.
As we saw with the disappearance of Australian pilot Frederick Valentich, having “solved“ an intriguing case generally means picking and choosing some facts fitting the pet-theory of the “Skeptics“, while ignoring all other elements or explaining them away by resorting to incredibly unlikely ad-hoc hypotheses.
