About three or four billion years from now the Milky Way Galaxy and the Andromeda Galaxy are going to collide with each other. While a galactic collision isn't a meaningful hazard to the objects within the galaxies, since stars are so far apart from each other that they are very unlikely to collide, both galaxies' structure will be churned into mush. And this is what it will look like from the perspective of our Sun as it is flung into a long, megayear orbit around the wreckage.
A span of time so long that the very framework of the sky melts away. Would it be scarier to think that no human will be alive to see this? Or would it be scarier to think that a human will?