[ExI] Monkeys in Space (was: Re: Concerns Grow Over Conditions on Navy Carrier)

[Ben Zaiboc]

On 14/08/2026 14:16, BillK wrote:
> Nine months, and some crew members are becoming unstable?
>
> With all the talk about trips to Mars soon, I asked how long that would take.
> The fastest estimate was approx. 9 months going, wait 500 days, then 9
> months back.
> The round trip takes approx. 3 years.
> Can the crew remain stable for that long in isolation?
> Can they carry enough supplies for three years?


You're referring to psychological stability, but I think there's something more important: physiological stability, also known as health.

I've said it before, and I'll say it again: Monkeys (i.e. humans) are not going to colonise space.

Apart from all the other (many, and considerable) problems, there's one that we don't have any idea how to overcome, that people seldom talk about, that seems to be a show-stopper, and that's gravity.

Humans need quite a lot of gravity to remain healthy. Unless and until we figure out how to keep a human healthy in gravity less than about 0.6g, nobody is going to be living for any length of time on any of the potential candidates for colonisation. The only planet that offers enough gravity to keep humans healthy, apart from the earth, is venus, at about 90% of g. The rest of them: mars, the moon, any of the jovian or saturnian moons, mercury, etc., have gravity far too weak for humans to remain healthy. And of course, venus is off limits for a looong time, assuming we try to terraform it (which might not even work, given how much closer to the sun it is than earth).

The only way biological humans are going to be able to live happily and healthily off-earth is in very large rotating habitats, and I don't see them being constructed any time soon, and maybe never.

I imagine that any manned mars expedition will return corpses, if it returns anything at all. Any attempt to settle mars is doomed to failure, either because corpses (or very sick people) will be all that arrive there, or because any living humans arriving will soon turn into corpses. At the very best, we would have colonies full of people with severe osteoporosis and various other physiological defects which would probably be fatal over a period of years. Maybe evolution could solve the problem over time, but that's a huge and immoral gamble to take.

I suppose we could try to build 'centrifuge cities', but that's probably ridiculous.

If we want to spread beyond earth and remain biological, we'd better figure out how to build large rotating habitats with robust independent ecosystems, and forget about planets. Or develop modifications to human physiology that enable us to survive in >0.6g indefinitely, and at the moment we have no clue how to do that.

My money is on non-biological humans (and/or non-humans) being the ones that will colonise the solar system. It won't be Monkeys in Space, but it might be Robots in Space.

If anyone has any convincing rebuttals to the gravity argument, I'd like to hear them.

-- 
Ben