Tantalising signs of life (biosignatures) on a distant exoplanet.

It depends what kind of alien life. I think discovering a few little microbes or something similar somewhere else isn't going to cause much of an issue. It's discovering intelligent alien civilisations that would be catastrophic for many of the Earth's institutions, the most obvious of which being our Earth-centric religions.

I agree but I believe your scope is limited. Discovering evidence of prior life on our neighbour (Mars) indicates that something is wrong, geopolitical stability is not written into the fate of civilisations.

Not sure I'm understanding your point. Of course civilisations can and have fallen apart many times throughout history unrelated to alien life, but I believe that conclusively observing and proving beyond all doubt that another intelligent alien civilisation with presumably completely different religious, spiritual and cultural beliefs is out there would have cataclysmic effects for our own sense of identity, politics, religion and so on.

Yes, all of those things you have established are perfectly concrete observations. But in addition, answer me this. If, in fact, life is so common that we should see evidence of it in our closest of systems, then where are the remnants of technologically advanced civilisations? The fact of the matter is that some event, be it the invention of particular technology or sociopolitical instability leads to the erasure of complex (intelligent) life almost all of the time. That being said, finding microbes on another planet is horrifying.

Well I don't believe life is that common, or at least not intelligent life. We haven't observed even a fraction of nearby solar systems, let alone ones further away. Moreover, when observing distant planets (and even ones in our own solar system) I don't yet believe we have the ability to view the surface, we can often only analyse the atmosphere and make inferences from that.

Really, you think microbes on another planet is horrifying?? I would think it's pretty common actually, with all the gassy sh!te out there there must be something that's evolved to feed on that creep lmao.

Everything evolves, in the right conditions all life will tend towards a greater maximum return in the longevity of its genetic information. If these things are quite as spontaneous and likely to occur as the evidence suggests, then our very existence is called into question. As you mentioned earlier, it will shake religious and political institutions to their core. Merely the fact that simple life originates so readily suggests that intelligent life should do so too (as some evolutionary branch)

Life itself was something that was believed to be incredibly rare, with only one confirmed place known to harbour it. What happens then when we are finally thrown from that pulpit. It is horrifying in the sense that it will precipitate our downfall, at least in the short-term.

Well I mean bear in mind that even on Earth which is teeming with organisms, intelligent life isn't common. Based on the perimeters we use we can say it's limited to us in the most exclusive sense, but can include other higher primates, proboscidea and certain species of cetacean in the more general. And that's because it takes millions of years for that kind of evolution to take place. And considering how distant other planets are, intelligent civilisations may be long extinct by the time the light reaches us. As you alluded to, developing something like faster than light travel would be an amazing way to explore more quickly and cover a larger area.

Something you might be interested in, hope we can talk later: https://arxiv.org/pdf/1806.02404.pdf

Yes, all of those things you have established are perfectly concrete observations. But in addition, answer me this. If, in fact, life is so common that we should see evidence of it in our closest of systems, then where are the remnants of technologically advanced civilisations? The fact of the matter is that some event, be it the invention of particular technology or sociopolitical instability leads to the erasure of complex (intelligent) life almost all of the time. That being said, finding microbes on another planet is horrifying.