So I have this idea that a super advanced being travels across the galaxy and is terraforming/xenoforming every planet that CAN be modified for life, not just Carbon based Earthlike lifeforms but different kind of exotic life (alternate biology). It will change most of the planets and bigger moons in our solar system, but in this post I want to ask about our moon. Note that this being i write about is so advanced that getting required energy or materials is not a problem: so don't bother with the "how to do it"explanation.

So again:would a Chlorine atmosphere "work"in the case of our closest satelite? I know that our atmosphere would "escape"from the moon's grasp,but Chlorine is much heavier.

And now let's explain the details: By "Chlorine atmosphere" I mean something like Hydrogen,Oxygen,lots of Chlorine. If you think some other gasses are needed (probably they are)that's all right.

The solvent used will be muriatic acid.

Photosynthesis:muriatic acid combined with carbon dioxide would produce formaldehyde,Oxygen and chlorine.Animals would drink muriatic acid and eat foods filled with CH2O. Lets say they will inhale Oxygen and exhale Carbon Dioxide (feel free to suggest something else).

Looks: Moon would appear very green(organisms could metabolize Chlorine)and have brownish landmass.

I want to add that I edited this question,and my previous version of this post was quite diffrent,hence the answer below (about a silicon-based system). That was great answer,by the way. However, my question needed to be more focused, so it changed drastically, so do not mind the "silicon-based"part.

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    $\begingroup$ You don't necessarily need an atmosphere: worldbuilding.stackexchange.com/questions/10697/… $\endgroup$ May 24, 2021 at 22:04
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    $\begingroup$ Non-carbon life is a bit of an unknown, so this question may be viewed as opinion-based. Think about the question and what kind of non-carbon life you want. If you can't say, then the question may be unanswerable because we're guessing about the nature of the organisms and what they might need. $\endgroup$
    – DWKraus
    May 24, 2021 at 22:16
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    $\begingroup$ I apologize for VTCing your first question, but SE's model is one-specific-question/one-best-answer and this question can't meet that criteria (or several others outlined in the help center). You basically asked us to tell you how to convert the moon to handle any undefined lifeform. Considering the only evidence of life that we have is here on Earth, that's asking to shoot an arrow through fog at a moving target. Please define the one and only one lifeform upon whose behalf you wish to xenoform. The more specific you can be, the better. $\endgroup$
    – JBH
    May 24, 2021 at 22:19
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    $\begingroup$ @MolbOrg Even after edits, this question is unanswerable. Querents are still responsible for meeting the basic expectations of Stack Exchange. Mishima has not defined the target life form ("non-carbon" is nowhere near specific enough for SE's or our standards). Without that target, this is an open-ended, opinion-based, not-possible-to-pick-a-best-answer question. $\endgroup$
    – JBH
    Jun 2, 2021 at 14:08
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    $\begingroup$ @MolbOrg You're welcome to debate that in Meta - but the reality is that we're bound to SE's basic format. It is, after all, their service, not ours. $\endgroup$
    – JBH
    Jun 2, 2021 at 23:17

1 Answer 1



Going with your suggestion of a silicon-based system, I'm going to suppose that the aliens convert a thick layer of the lunar regolith into polydimethylsiloxine, with occasional or perhaps frequent substituents on the methyl carbons. The effect of this is to give the Moon a viscoelastic "ocean" that is stable in vacuum and ultraviolet light. See this paper for some possibilities - the material can survive vacuum exposure and is compatible with living cells, even of Earth life.

enter image description here

This substance finds widespread application on Earth - the Wikipedia article mentions Silly Putty, caulk, condom lubricants, hair products, and ... ugh ... oil used to cook McNuggets?? So we can imagine a wide range of properties. The "ocean" can be relatively clear to allow sunlight to some depth for photosynthesis. Perhaps we can have chains of different lengths and degrees of branching (whenever we attach two Si to the same -CH2-) or different substituents added at different depths of the "ocean". Some layers might be conducive to holding and transporting water if we have some minor niches for Earth life in mind.

I think there are many ways to go with this, but you could get a fairly convincing 'ocean ecosystem' set up using the silicon, oxygen, and carbon found on the Moon. The amount of hydrogen in this molecule is iffy - there is water to be found, but this is tough. Maybe someone could suggest a way to replace some of that with oxygen or other more accessible elements while maintaining a useful set of chemical properties.

  • $\begingroup$ Great comment,and it gave me an interesting idea i could go with this.Meanwhile,however,,i had to change the question drammatically,as it needed to be more focused.Do you have any idea if Chlorine atmosphere would work?I described all the details in the description.I ask because im afraid that most of the atmosphere (besides Chlorine,there are other things too)will escape from the moon or maybe it would affect the Earth negatively. $\endgroup$
    – Mishima
    Jun 9, 2021 at 19:36
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    $\begingroup$ I think you should have made it a new question. I lean against it. Cl2 is an oxidizing gas like O2, and an old popular idea for slightly different sci-fi worlds. But when O2 meets electrons, you get O2-, which is water waiting to happen. When Cl2 meets electrons, you get Cl-, which remains a salt except in very acidic conditions. And there isn't much that won't reduce chlorine! Water can go on and react many ways potentially leading to regeneration of O2, but what does the Cl- do but find a crystal to hole up in indefinitely? $\endgroup$ Jun 9, 2021 at 22:37

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