It is very difficult for us humans to really grasp that unknown unknowns are real and have an effect. On some level, we assume that if we don't know something,

It is very difficult for us humans to really grasp that unknown unknowns are real and have an effect. On some level, we assume that if we don't know something, it's not worth knowing, or we confidently make things up not even realizing we have done so. This bias influences us to believe that we know far more than we actually do. ...we should be able to recreate or predict some environments that would yield the same magic... Why should we? Physics and chemistry derive from observation. Theory is descriptive. 1) Our experience with chemistry outside of the Earth environment is almost entirely theoretical. Only very expensive equipment can achieve, for only fractions of a second, in only microliters volume, extremes of temperature, pressure, magnetic fields, and never any environment with higher gravity than our own. We have no experimental access to, not to mention actual intuitive understanding of, the widely diverse environments that exist in the Universe. So, our experimental knowledge is lacking. 2) Were we disembodied minds with no actual experience of the world, could we predict the existence of terrestrial life from first principles if given complete access to current knowledge of terrestrial physics and chemistry? Probably not. We don't know what makes a good environment for life, other than that we look around on Earth and see it everywhere. So, our theoretical knowledge is inadequate. 3) Even what we perceive and define as life, sentience or civilization is limited by our lack of experience. If trees for example had a rich storytelling tradition, epics unfolding over centuries perhaps, how would we even discover that or understand them? Trees are far more relatable than aliens are likely to be given that we share a common ancestor. The concept of, say, wind patterns or waves or nebulae being alive or sentient is easily dismissed, but again, our definition of life is narrowly defined by our single data point, our interests and outlook conferred and constrained by our evolution. Is it useful? Is it dangerous? This is the sort of thing that informs even our ability to perceive something as worthy of attention. Before microorganisms were discovered, the concept of invisible critters was laughable. So, our understanding of what we're looking for is inadequate. I suspect that the evidence of alien life is all around, but it's just too different even to be interesting.