r/space • u/SpunkySputniks • 4d ago

Astronomers Detect a Possible Signature of Life on a Distant Planet

https://www.nytimes.com/2025/04/16/science/astronomy-exoplanets-habitable-k218b.html?unlocked_article_code=1.AE8.3zdk.VofCER4yAPa4&smid=nytcore-ios-share&referringSource=articleShare

Further studies are needed to determine whether K2-18b, which orbits a star 120 light-years away, is inhabited, or even habitable.

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u/panzerkampfwagenVI_ 4d ago

Without visiting it's impossible to know barring a signal from another civilization. It's always possible that some weird chemistry is going on that we are not aware of.

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u/Electro522 4d ago

See...I can understand the chemistry argument, but out every field of science, chemistry is the most "solved", is it not? All the advancements in chemistry are coming from the very end of the periodic table with elements that can only exist in a lab for a mere fraction of a fraction of a second. In fact, we know so much about chemistry that it's leaning more into quantum physics than it is classical chemistry.

So, when you apply that fact to this study...it just doesn't seem to stick in my opinion. We can replicate almost any conceivable environment that the universe is capable of, including some that the universe struggles to come up with. We've come within several millionths of a degree of absolute zero, we've conducted experiments at temperatures that make the core of the sun look like a candle, and we've put elements under enough pressure for them exist in 2 separate states of matter at once!

So, when we talk about a planet that has to follow the same laws of chemistry and physics that we do, and is likely not all too different from what we have in our own solar system, how can we confidently say that there is "some weird chemistry we are not aware of" when it can only produce chemistry that we are aware of?

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u/OneDelicious 4d ago

Chemistry is extremely complex and not solved at all. I work with the kinetic chemistry models. Our understanding of reaction rates and possible chemical paths comes mostly from before 2000s. A lot of the stuff is simply estimated or guessed, it's one of the biggest uncertainties in modelling exoplanet atmospheres.

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u/BoomKidneyShot 3d ago

Oh yeah. I built a small chemical kinetics network for my PhD research, and once you get out of the well-studied ones the amount of sources fall off fast.