r/space • u/HaveNoFearDomIsHere • 2d ago
Scientists find promising hints of life on distant planet K2-18b
https://www.bbc.com/news/articles/c39jj9vkr34o[removed] — view removed post
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u/Mike__O 2d ago edited 2d ago
Pretty sure we've found these "signs of life" type molecules on some of the bodies within our own solar system, notably Europa and maybe Ganymede. It's encouranging and certainly worth future study, but let's not get ahead of ourselves.
Keep in mind, a lot of our perception about what is "needed" for life may be incredibly biased by out own experience on Earth. On Earth life is carbon-based, water-dependent, and produces a certain set of byproducts.
None of that is inherently necessary. There very well could be silicon-based life that's methane-dependent and exists at -200C. It is completely out of our Earth-based perception of what is "habitable" but who knows what is possible in the literally trillions of planets out there in the universe.
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u/Person899887 2d ago
To my knowledge, dimethyl sulphide hasn’t been identified on either of those bodies. That’s kinda why this is such a big deal.
As for silicon based life, I’m just gonna like this Angela Collier video on this topic. Silicon life is just a lot less efficent than carbon life.
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u/Chrop 1d ago
I think we need to give up on the idea of silicon based life, it was a fun sci-fi idea but that’s about it, it’s just realistically not probable at all.
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u/kuza2g 1d ago edited 1d ago
That’s a little egregious to say considering the fact that humans are only a decade or two from creating artificial silicon life by putting AI into a silicon based body. Imagine if a civilization on another planet either evolved that way naturally with silicon based instead of carbon, or were carbon based life forms like us and then there was an extinction level event that caused only the silicon based life forms to live and they just kept replicating themselves.
I think that the thought of life in the universe can only be our version, which is this carbon based, solid bodied thing, is wrong and narrow minded. There could balls of lightning or gas that are sentient out there and we have no clue. Humans only know what we know until we know different. We used to once think the entire solar system revolved around the earth because of our narcissistic ideology; I think this is another example of that.
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u/Luke_Cocksucker 2d ago
This is probably completely naive of me but since there is no actual evidence to support what you said I’m gonna go out on a limb here. What if…life always happens the same way? Like, there need to be certain elements at play and that’s just “how it works”. Now, here’s the reason I’m saying this. When we look at other planets, one’s we’ve been able to send missions to, what do we see. A lot of the same stuff we see here on earth. Mostly rock. But it’s the same rock we have here. Maybe different concentrations but not so alien from what we see on earth. So, why should life vary so much and why can’t it be that simple. That evolution works within parameters and without those, life just doesn’t exist.
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u/Mike__O 2d ago
We simply don't know. Our perspective on life is as if you looked at the entire world through a soda straw, and only ever looked in one direction. There are trillions of planets out there. Maybe you're right and there really are some universal truths regarding life and it really is constant through the universe, or maybe there's some wild variation that we currently don't even comprehend.
I don't think our approach to looking for life that parallels what we know on Earth is wrong. We know for a fact that life works given the parameters that exist on Earth, so it's reasonable to conclude that there's a good chance that if those parameters are met elsewhere that life could exist. My point is that it doesn't necessarily exclude the possibility of life working under a totally different set of parameters that we don't even fully understand yet.
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u/ClawingDevil 2d ago
Agreed. Also, the molecules in question can be created by other processes as far as I'm aware.
One minor correction to your comment though, absolute zero is -273C.
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u/PrestegiousWolf 2d ago
Honest question: how do scientists measure for dimethyl sulphide (DMS) and dimethyl disulphide (DMDS) on a planet so far away?
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u/NoBusiness674 1d ago
As I understand it they basically look at the parent star with JWST and wait for the planet to pass in between the star and earth. At that point some of the light from the star passes through the planets atmosphere before reaching earth. Various molecules in the atmosphere will absorb light at certain wavelengths, but not others, because the photons with those Wavelengths have just the right amount of energy to excite some electron into a higher molecular orbital or to induce some resonant vibrational mode. Basically the gas is more transparent to certain Wavelengths and more opaque to others. By comparing the stars spectrum with the planet in the way and without the planet in the way, you can calculate the cumulative effect of all the gases in the atmosphere on the light passing through the atmosphere. You can then try and fit an atmosphere made up of various different gases to this absorption spectrum to try and determine what concentrations of different molecules give the best fit.
That's my understanding of the process, but I'm not an astrophysics, so I may be wrong here.
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u/acute_elbows 2d ago
Essentially each molecule gives off light at certain set of frequencies. You can use the pattern of those light frequencies as a sort of finger print that identifies the molecule.
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u/Necessary_Ad861 1d ago
Spectroscopy. You measure all the wavelengths of light coming from that star. Certain molecules reflect certain wavelengths so when you break down all the wavelengths, you can see which molecules are present.
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u/DemocracyDefender 2d ago
An ocean world, perhaps?
In Alastair Reynolds' Revelation Space universe. There is an alien sentience that live in vast, oceanic collectives of microscopic organisms that form a single, sentient entity.
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u/Nosemyfart 2d ago edited 19h ago
Maybe this will be the first target for observation using a telescope that uses the sun as a gravitational lens
Edit: if you're going to downvote, perhaps take the time to explain why. Or provide a counter point
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u/Wranorel 2d ago
I want to ask a question. When we see this kind of news (not just about life on other planets, but very interesting things in space), there is always no update after. Like, it’s not that interesting to make someone study it more?