"Future Human Space Travelers Without Artificial Gravity?" Topic

So is this what could be expected if the human race were forced to abandon Earth prematurely, because if some post apocalyptic event, and had to take on a nomadic life in Space before artificial gravity was mastered?

Will the spacefaring post-humans going to look like Alien Greys and, if they survive even further into the future, eventually evolve to look like Dune's Third Stage Guild Navigators?

Dan
PS. I also seem to recall a post apocalyptic novel like that, with the "human" descendants (looking like the Third Stage Navigators) returning to what they thought was a devastated Earth only to find that there were still human-looking survivors there after all. I wish I could remember the title of it though.

Wasn't the Navigator's mutation supposed to be from pre-longed saturation in the Spice?

Anyway, short term at least most books dealing with this tend to say humans would lose muscle mass becoming more skeletal, perhaps changes to the eyes to allow better vision with limited light etc.

I did read one book which had humans modified for living in space by replacing the legs with a second set of arms amongst other mods.

The long term space station studies showed that in a year they lost a lot of bone mass too, didn't they?

And they ended up gaining an inch or so in height, at least temporarily.

Dan
link

Yes, the navigator's mutation was from prolonged exposure to spice, and unless my memory is faulty, they were not described at all like the version that wound up in Lynch's movie.

Something tells me by that time we'll have learned how to solve the problem by, oh, I dunno, spinning the habitat. *Ahem*.

Of all the problems inherent in long term space habitation, creating an artificial gravitational environment is the least of them.

Parzival,

OR … they'll figure out a way to embrace weightlessness and dispense completely with the need for gravity.

Of course, by then looks won't be an issue since the entire society will probably be genetically modified/manufactured in vitro*. They'll just be a society of drones with the leaders in charge of all reproduction. :)

Thank God I'll be long dead by then!

Dan
* link

If they're floating through space without gravity, then a few things would happen:
1. their extremities would shorten since moving longer limbs quickly would cause them to overbalance and counter rotate.
2. since their internal organs would no longer be pulled 'down', they would tend to float 'up' and become more centralized.
3. the rib cage would expand to accommodate the organs. And probably become more spherical to protect to intestines.
Basically, they would look more like beach balls with short arms and legs. Hey! look at me, I'm evolving!

Stryderg: "Hey! look at me, I'm evolving!"

I think many of us are men way ahead of our time. :)

Dan

The Belters in the Expanse series of novels are described as being somewhat elongated, thin, with slightly larger heads. They can't tolerate gravity and childbirth is risky due to no or low gravity, as is any kind of surgery. Fairly plausible and detailed description of a possible form of human adaptation due to low/no gravity.

Since centrifugal "gravity" is simple enough to do with 1930's tech, there's no reason to not have at least some parts of a ship that have grav wheels.

I think you're talking about a minimum 40m diameter, however, to avoid motion-sickness. A 40m diameter centrifuge spun at 6.67 rpm will give you 1 gee, and a big station like Babylon 5 (with I think a 200m inside diameter to the gardens) only needs to be spun at 2.98 rpm for 1 gee.

So a ship like the Bebop from Cowboy Bebop (maybe 50m long?) is a bit too small for a decent grav wheel, but a larger ship like the Amaterasu from Starship Operators (310m long, 105m wide) is good to go. And obviously, a big can like Babylon 5 is fine.

You'd also have two counter-rotating wheels if you didn't spin the entire ship/station.

But I wouldn't be surprised if humans modified for living in space ended up with opposable thumbs on their feet. Makes it much easier to leave two hands on the ship and one hand on the work, plus lifelines, of course.

Something like Bran Do Castro from the Infinity range:

Though I admin Bran is supposed to be The Monkey King in space, the mod to the feet makes sense. If I was going to spend the rest of my life in space, you bet I'd consider getting new feet!

Lion,

The opposable thumb on our feet makes sense!

Dan

A few things to remember:

1.) A ship under acceleration ("under thrust") is NOT in zero G. Instead it has an effective "artificial" gravity internally which is directly towards the engine nozzles (directly away from the direction of travel). This artificial G is equal to the amount of Gs produced by the engine thrust. So in such a case, the size of the vessel is irrelevant; all that matters is that it's accelerating.

2.) If a ship is not accelerating, then the internal conditions are effectively zero-G. At this point, however, a viable technique, regardless of ship size, is to release a counterweight on a tether whose length is equal to the diameter necessary for a comfortable "grav wheel" as Lion names it. The ship and the counterweight then spin around the central point of the tether, producing spin gravity in both. The counterweight might be cargo or other ballast which is not needed to be accessed during drift travel. (Indeed, the ship's engines might be the counterweight, and the crew and passenger section be the part at the other end of the tether.)

3.) Zero-G and 1G have a lot of difference between them. It might be possible that a fractional G environment is sufficient for health maintenance and body development (even birthing), and such an environment can be created with much smaller comfortable diameters for spin. This is actually an interesting question, as we do not know the effects of sustained low G on health at all, absent preceding and subsequent extended zero-G sessions (the Lunar landings).

4.) Our organs pretty much require gravity to work well long term. That may not be something we can easily correct, or evolve away from.

Fritz Leiber considered this in A Spectre is Haunting Texas – an eight foot tall resident of a circumorbital colony visits Earth and has to stay in an exoskeleton to move

link

Lois McMaster Bujold had the Quaddies – genetically engineered humans for four arms (one pair instead of legs, not 4 arms plus legs). They also had other adaptations for zero g.

en.wikipedia.org/wiki/Falling_Free

Evolution only works if genetic changes improve your chance of leaving offspring behind.

Some of the enthusiasts in Starship Century ( link ) and Centauri Dreams ( centauri-dreams.org ) discuss getting the population of the solar system up above 1 trillion so we'd have an economy large enough to afford a few colony ships to other stars. Should be ample opportunity for evolution.