An interview between the aliens and a science organization, with no redaction, no editing, no cuts to commercials, broadcast live on every channel. This is assuming we find a way to communicate. Even then I would probably be a little skeptical.
Now if you want to convince me that aliens visited here millions of years ago, I might be on board. Ancient Sumerian texts paint a fairly clear picture of the "Sky People" and their tampering with DNA often represented as the tree of life covered in the Book of Enoch, somewhat represented in the Torah and missing from the Christian bible covers the sky people a little bit as well. It is missing many of the scrolls however.
Until such time, I will assume its the same clever but childish games that military organizations and governments have been taunting each other with since WWII. i.e. the microscopic screw competition between the U.S. and Japan, the chirpsounder noise floor comms between the U.S. and the Soviet Unition, the typewriter vault incident between U.S. and Russian intelligence, and so on. I don't have links to any of these, sorry.
I would need to see the spaceship in space, using a telescope with my own eyes. Or at the very least someone credible pointing it out, like NASA, JAXA or ESA (preferrably all of them). Also an explanation of how the civilization managed to be unseen, or how are they traveling FTL.
What isn't discussed much is incentives. Currently, it doesn't seem that aliens are acting in a way that would be consistent with their incentives. If they are powerful enough to get around the galaxy, they'd definitely be safe with closer encounters with us. Nothing we could do about it even if we didn't like it.
I also imagine they would be bonded by morality similar to the way humans are and want to help us and the planet generally if they knew we existed. (More bellicose civilizations are less likely to achieve interplanetary travel before they blow themselves up.)
Now if you want to convince me that aliens visited here millions of years ago, I might be on board. Ancient Sumerian texts paint a fairly clear picture of the "Sky People" and their tampering with DNA often represented as the tree of life covered in the Book of Enoch, somewhat represented in the Torah and missing from the Christian bible covers the sky people a little bit as well. It is missing many of the scrolls however.
Until such time, I will assume its the same clever but childish games that military organizations and governments have been taunting each other with since WWII. i.e. the microscopic screw competition between the U.S. and Japan, the chirpsounder noise floor comms between the U.S. and the Soviet Unition, the typewriter vault incident between U.S. and Russian intelligence, and so on. I don't have links to any of these, sorry.