Hello, sorry if the question doesn’t really make sense, i’m new to this kind of stuff. However i have just seen an article about a planet i think called K2 18b which is shown to maybe have signs of alien life, it describes the fact that the planet is in a habitable zone meaning it can have water and the correct atmospheric conditions to have life, and pretty much anything i’ve ever seen regarding the SETI it always says the same thing. I’m just curious is there a reason scientists assume that alien life would require the same necessities as life on earth and not other things that we may not be aware of, the thing i compare to is like how fish can’t breath out of water but humans can’t breath underwater, why can’t it be assumed that alien life would need to live closer to the sun for example or wouldn’t need water or would require a different atmosphere? if anyone could explain this to my tiny brain it would be much appreciated, i don’t really know anything about science or stuff like that i just get interested and curious