If a supernatural event occurred, how would you tell?

[Waratah]

Suppose that what appears to be a supernatural event happens right in front of you. Say a glowing man with wings floats down to earth in front of hundreds of people, makes an accurate prediction of a future improbable event, maybe raises a few verifiably dead people for good measure, and then disappears in a great ball of light.

Even though such things appear to defy known science, and seems to be an instance of stereotypical miracles of religions happening before our eyes, could we conclusively say that it was a real supernatural event? Wouldn't the most probable explanation be that it was an alien trickster from an incredibly advanced alien civilization, perhaps one that discovered a way to see into the future, teleport, and "raise" the dead?

Consider: alien explanation versus supernatural explanation. Even though both are seemingly incredibly unlikely, I would think that the alien explanation is far better explanation than the supernatural explanation in any instance of an apparent miracle since given our scientific knowledge, there seems to be a good a chance of life developing on other planets in our universe.

What's that saying?... something like "any sufficiently advanced technology is indistinguishable from magic."

My bold to your post, because its this part of events that I don't think I could have any explanation(for me anyway). Even though I may not be able to explain it, I believe I would would be more inclined to say that there is now a lot more I do not understand. Just because I cannot explain it certainly does not make it supernatural.