Can’t it be possible that there is life even on the moon but the life-forms there are biologically adapted to those conditions…in short, why are we always looking for our own frame, i.e. searching for water?
This is a great question and one that we could all have fun answering. Let me start by answering the second part of your question first. There’s a common saying out there that says “go with what you know.” At this particular moment in our scientific history, we only really (barely) understand and are able to recognize life “as we know it.” And currently, that life requires liquid water. And currently, that life requires liquid water. And on the moon’s surface, temperature fluctuates between (average) -184 C (-300 F) in the shade and 111 C (232 F) in the sun. While it is possible that water ice with cometary origins possesses organic material or even spores (Panspermia Hypothesis), that water ice is in permanently shadowed craters on the poles of the Moon and thus frozen at ~ -200 C. Thus there is no presence of liquid water on the moon. Tied into that is the hostile radiation environment from solar and galactic energy which is energetic enough to destroy all cellular machinery. However… The fundamental problem here is that we don’t always know what else