I am a post-human adapted for permanent life in vacuum and micro-gravity. How might my physiology and biochemistry overcome the following challenges?

Please note I have a strong cultural aversion to augmenting my body in order to help me survive: i.e. enclosing myself in artificially-constructed protective shells, etc.

Part 1: Radiation: I am constantly bombarded by ionizing solar and cosmic radiation that punches through matter like little atomic cannonballs. I think I've worked out how to protect myself - by having a super efficient DNA and cellular repair setup and a protective skin - but I also want to prevent overexposure by being able to sense potentially dangerous levels of radiation, such as from a solar flare. What's the best sensory apparatus for the job?

See Part 2 on temperature control

See Part 3 on metabolism

See Part 4 on movement

See Part 5 on senses

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    $\begingroup$ Good Chairman, take a page from @Demigan and his supersoldier idea where s(he) broke up a many paqrt question in several questions. worldbuilding.stackexchange.com/questions/112777/… Your question is actually 5 different questions. I recommend you break them up and post them one at a time with a little time between each, so as to not overwhelm. I have taken the liberty of starting this for you, reducing your question to just the first one about radiation. $\endgroup$
    – Willk
    Commented Nov 4, 2018 at 22:15
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    $\begingroup$ Possible duplicate of How can I make humans not negatively affected by radiation? $\endgroup$
    – Mołot
    Commented Nov 5, 2018 at 6:43
  • $\begingroup$ @Willk since the answer has been changed now I'll refer to my question that deals with radiation specifically: worldbuilding.stackexchange.com/questions/111275/…. There's some nice stuff in there about Mole rats and how Elephants reduce the chance of cancers etc. $\endgroup$
    – Demigan
    Commented Nov 5, 2018 at 7:24
  • $\begingroup$ Thanks @Mołot, that thread answered part of my question and I have now edited accordingly $\endgroup$ Commented Nov 5, 2018 at 10:42
  • $\begingroup$ You have two questions in this post. 1) How can I make humans radiation proof (see duplicate suggestion), 2) How can humans be enhanced so that they can detect lethal levels of radiation using their body, and presumably before dying. $\endgroup$ Commented Nov 5, 2018 at 14:18

5 Answers 5


If you are just worried about ionizing radiation then there may be biological solutions ...

1) Build a radiation-proof skin/shell. Possibly impractical, as radiation in space can be fairly penetrating - even a few mm of aluminium won't keep it all out. But you could develop a species with a very thick skin (inter-locking plates to maintain flexibility like an echidna or armadillo?) full of heavy metals. Would be ugly, heavy and lacking in mobility depending on how much shielding you required. Or could just limit the shielding to the reproductive system in which case people might have short cancer-ridden lives but would still reproduce reliably.

2) Reduce the effects of genetic errors. For example - upgrade the immune system to actively fight all likely types of cancer, or add nano-bots to continuously scour the body of tumors and other radiation-induced irregularities.

3) More high tech - harden the genetic code so it is more immune to errors resulting from ionizing radiation. This might be done a number (or combination of ways)

  • Add a lot of error-correction. For example, you could duplicate or even triplicate the number of copies of each gene within each nucleus. Then when generating new proteins etc from the genetic code each cell would check if all copies of the code were identical. If so, it would 'run' the genetic code, if not it would discard its own nucleus and get a 'copy' from a neighboring cell. Continuous 'data-checking' to test that your multiple copies were in agreement. Obviously requires significant re-writing of the DNA/RNA manipulation chemistry in cells.
  • Harden the DNA/RNA coding. For example, move from 3 codons to 4 or even 5 codons in the 'table' that relates codon ordering to amino acid placement in proteins. Probably an even more significant change in biochemistry.
  • Harden the chemistry of genetics itself - replace the coding mechanism by some more robust chain molecule/system that can still carry genetic info. Siliconized sugar back-boned DNA, multiply cross-linked 2-D genetic materials, storage to nanoscopic mineral structures, whatever...

Previous generalist answer below:

You almost certainly mostly mechanical. Life is very adaptable to extremophile adaptation (very hot/cold, highly acidic, heavy metal poisons, radiation, low nutrient availability) but even after millions of years of evolution, the organisms that can live in the most extreme settings are inevitably very simple organisms. For example, there are plenty of lichens in Antarctica but no trees or higher plants, and no permanent resident vertebrates. Bacteria adapt to hot springs, but you won't find fish living in them. There appear to be physiological limits to natural adaption of mammals to very high altitudes. So far more practical than trying to bio-engineer a complex air-breathing organism, with a resource-hungry brain, to survive in space - it would likely be much simpler to either: - take just the important 'parts' (brain, some glands, some internal organs) and install them in a mechanical 'body' designed with its own radiation shielding, reactor, long-term food supply (or microbial bio-farm that recycles your waste products into food), thrusters, grabbing arms, radar and radio. Or,
- go the whole hog and download personality into an entirely mechanical 'body'.


For starters, they would be tiny and not humanoid anymore.


And thats probably also the end of it. Unless your humanoids have found some system to use uranium or Iron and dissolve that into oxygen. You'd also need to concect as little heat as possible to remain warm, so either become larger which is hard due to the oxygen problem or have a specific metamaterial to keep in your heat.

For radiation I would use boron nitrate Nanotubes: https://en.m.wikipedia.org/wiki/Boron_nitride_nanotube

They are already in development for spacecraft.


Come the technological singularity, humans could be digital and capable of existing in a digital world of their own making.

The computers running these digital worlds can already exist in space. Humans will only have to load into physical bodies if they want to or need to act in the physical world.

You make the assumption that humans would organically adapt to exist in space but that would never happen. Space is too harsh and uncomfortable for humans to want to when they can live in a world of their own design.

  • $\begingroup$ There is no technological singularity in my world, and a strong regulatory and enforcement framework exists to protect what you currently call AI from exploitation. This means that space-based industries are acutely reliant on human labour, and biotech and geneng firms have invested in the development of vacuum-adapted post-humans to better meet such labour demands. $\endgroup$ Commented Nov 5, 2018 at 10:40
  • $\begingroup$ So AI is protected from exploitation but genetically exploiting human workers is ok? Interesting...... $\endgroup$
    – Thorne
    Commented Nov 5, 2018 at 23:50
  • $\begingroup$ Yes, those AI monsters essentially rule the inner system and maintain a monopoly on AI-birthing tech - leaving my state enterprises no choice but to wield large-scale exploitation of homo saps and development of vacadapts. The suffering of the baselines serves the greater good. $\endgroup$ Commented Nov 5, 2018 at 23:56

There is evidence to suggest that melanin not only protects from UV radiation, but also from ionising radiation: https://www.news-medical.net/amp/news/20110824/Melanin-also-protects-from-ionizing-radiation.aspx

I'm of the opinion that this will be the first evolutionary adaptation that would arise to combat exposure to radiation. I would expect space-dwellers to be heavily melanised, and heavily melanised throughout their body as radiation in space is so penetrating. You would probably find an exceptionally heavy melanin presence around the reproductive organs.

As for detecting radiation, again the most likely scenario from an evolutionary perspective would be to repurpose the apparatus we already have. Extend our vision further into the electromagnetic spectrum and you can start to see radiation.

Also, I remember reading a fascinating account from one of the radiation threads here on Worldbuilding about someone who was working in radioactive cleanup from Chernobyl. Apparently you could walk pretty unharmed where they were, but tyere were little radioactive dust motes that if they touched your skin would itch/burn like sunburn. If you think about it, we already have a few methods for detecting radiation. Eyes for visible light, and whatever pain receptors we have for detecting radiation damage from UV.


I won't enter into any scientific details but, based on previous answers (@Penguino), I would consider hairs instead of scales.

It can be as resistant and protectives as scales (given it's the same material), is more flexible, more sensitive and can also help on your management of your temperature. So I think that instead of looking like a pangolin, aiming for the wookie style may be more efficient and polyvalent.

And I'm just thinking that feathers could also serve that role.


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