As we learn, we discover things that are inherently gloomy, that is, they confirm a certain negativity. For example, black holes, and stars. We now know our galaxy orbits a black hole, we know our sun will eventually explode, taking earth with it. In spite of these discoveries, we continue to work, play, learn and dream. We find true peace in the calm before the storm, even while studying the storm. There isn't much of a point to this topic, but it's something that fascinates me, we are incredible.
They are not within my lifetime, nor that of any of my future bloodline, so why should I care? That's why I am peaceful.
I find peace in knowing that things like that are inevitable. If there's absolutely nothing you can do to change it, then why worry?
I'm not very imaginative and it's 4am. I'm sure I care about other things, but the ones you listed I am at peace with.