In short, there is no way to tell the difference between alien minerals and alien life.
That’s why I was asking the question. I suspect that for every non-anthropomorphic definition of life there is a handy counter-example out there.
The most noticeable difference between Earth and Mars at interstellar distances is EM radiation, most of which is directly created by iron-based artifacts.
I am not sure whether this is an invalid point of view. Or that humans are the latest generation of machines designed to preserve and proliferate mitochondria. Or any other outside view of life.
That’s why I was asking the question. I suspect that for every non-anthropomorphic definition of life there is a handy counter-example out there.
I am not sure whether this is an invalid point of view. Or that humans are the latest generation of machines designed to preserve and proliferate mitochondria. Or any other outside view of life.
It’s not likely that we will encounter something like anything we have thought of, because can think of a trivial number of the possibilities.