|When you talk about nuclear activities leaving traces behind I am left to wonder: Isn't nuclear activities common place in the universe, would they really know that the leftovers wasn't just left over from natural occurrence?|
This question makes we think that just in case humanity disappears, we should build a way bigger pyramid than the pharohs did, if we can figure out how. Then there is that seed bank somewhere up in the Netherlands, I think, that is designed to preserve seeds of every known plant thing, and can withstand a nuclear blast.
I am reminded of an episode of Star Trek where they found a computer system left behind by an ancient race. I always figured that it would be a cool remnant. I don't know if we have the necessarily technology to build something that would stand the test of time but a lot of information could be left behind that way.
Such an encyclopedia could prove very useful if say it was society that would break down and bring us back to the stone age. I don't know if that is at all possible but I sure have heard of the thought.