Weightlessness for only hours and deep space life sustainment

[Nightside]

Ok, I think we have solved the laundry problem.

Moving back to weightlessness:

I think you are on to something @Spacescifi.

Let’s say warp bubbles are a thing, but that the bubble can’t get very big (~20m). Then ships are volume limited and couldn’t even have artificial spin gravity. 

The only reason magic gravity is so common in visual sci-fi is that it is much cheaper and easier to produce.

Edited May 22, 2019 by Nightside

[Spacescifi]

24 minutes ago, Nightside said:

Ok, I think we have solved the laundry problem.

Moving back to weightlessness:

I think you are on to something @Spacescifi.

Let’s say warp bubbles are a thing, but that the bubble can’t get very big (~20m). Then ships are volume limited and couldn’t even have artificial spin gravity. 

The only reason magic gravity is so common in visual sci-fi is that it is much cheaper and easier to produce.

 

As a writer I do not have such constraints, and if I did it for television I would just make it a digital cartoon.

I like weightlessness because not only is it awesome, it's cheap. Even in a setting with gravity generators, weightlessness would be more affordable for the common space traveler.

[RocketSquid]

Hours, days, maybe even weeks of null-gee is fine. It's when you get to months and years that problems really start.

Spin gravity is a lot easier if instead of thinking of it as centrifuges, we think of it as a cylindrical hab and a counterweight, connected by a tether. Plus, an emergency de-spin isn't actually that hard; simply have yo-yo weights around the craft's axis of rotation. 

Plant fiber or bacterial mats are the best strategy for clothes. If the only reason for washing is to get the odors out, you could potentially accomplish that by exposing the clothes to vacuum, which would cause any volatile compounds to rapidly outgas. Once an outfit became threadbare or too stained for use, it gets destroyed and fed to the CELSS.

Plants may not actually be the most practical, either in terms of energy use or nutritional output. In the long term you'd want some proper macroscopic plants, but in the short term there are a variety of microorganisms that would be more efficient, if rather gross. 

Microalgae are an obvious choice, but have some serious difficulties (spirulina will give you gout and doesn't have vitamin B12, chlorella needs processing to even be digestible, neither tastes very good).

Yeast is another choice, but needs something else to provide it with energy, probably an algae. Nutritional yeast tastes vaguely like cheese, and has a good deal of protein. 

In my opinion, however, the top choice for the base of the life support ecosystem is Knallgas bacteria. Rather than gaining energy from photosynthesis, they gain it by turning hydrogen and oxygen into water. With the addition of power from solar panels or a reactor, that water gets turned right back into oxygen and hydrogen. 

[DDE]

7 hours ago, RocketSquid said:

Spin gravity is a lot easier if instead of thinking of it as centrifuges, we think of it as a cylindrical hab and a counterweight, connected by a tether.

Since shielding yourself from radiation favours long, slender craft, you needn’t a tether - many designs have sufficient leverage already.

[kerbiloid]

The counterweight should be heavy.
Even if it is just a tether itself, enough massive to be a counter-weight without a weight on the other end.
And bulky.

So, the ship should be splittable, consisting of a nose and a rear halves.
A bonus: they can be capsules. So, the ship can be reusable.

Edited May 23, 2019 by kerbiloid

[RocketSquid]

13 hours ago, DDE said:

Since shielding yourself from radiation favours long, slender craft, you needn’t a tether - many designs have sufficient leverage already.

Yeah, but it doesn't exactly hurt to have it on a tether. That way you can have higher gravity for the same rotation rate. Plus, if you've got a reactor, you can use that as your counterweight to save on shielding.

10 hours ago, kerbiloid said:

The counterweight should be heavy.
Even if it is just a tether itself, enough massive to be a counter-weight without a weight on the other end.
And bulky.

So, the ship should be splittable, consisting of a nose and a rear halves.
A bonus: they can be capsules. So, the ship can be reusable.

I imagine the counterweight would probably be the propellant tanks, and the reactor if it has one.