I launch these things off every time I go camping, big ones, varying colors, we launch 4-5 at a time, and they look pretty similar. Chinese Lanterns

I don't think there is such a thing as "IRREFUTABLE" when it comes to anything related to UFOs anymore. Unless there is some sort of mass sighting, with thousands of people, multiple news crews, cameras, and shows a clearly visible daytime up-close footage, and in the US (come on, you know it's true), that's about all that will convince people.

But then, it would be some sort of Project Blue Beam technology staged event, with actors with all of that.

Face it.