What are the feasible means of keeping a space station existing and operational for thousands of years?

You have solar power, I presume you have reasonably intelligent robots, the solution is to take a clue from biology: Constantly, whether it is needed or not, replace every molecule of the space station with newly fabricated parts, smelt down the old parts, bring in new steel or whatever from asteroids. Make so no part of your station is ever more than 20 years old, and that goes for the robots too. All it takes is a constant investment of energy, which you should have in abundance from the sun. Make sure you are replacing those solar cells or furnaces while you are at it.

I say from biology, because our own bodies do the same thing; the only reason we grow old is we did not evolve a perfect replacement system or way to identify what needs to be replaced, so our telomeres get short and cells stop functioning properly. For a machine you don't have to emulate that, just emulate the idea: constantly retire the parts and replace with new parts. The atoms of iron, carbon and other metals never age; extreme heat will rejuvenate them, and you can recast them into steel just as good as new.

Added due to comments:

• I did not address high energy particles; those are atomic size and I assume can't cause any kind of strucural failure (unless in a beam intended for an attack); and if they did alter some steel, we can have sensors tell us where. On aircraft for example, we can run a tiny electric current through a part at one end and detect the shape of the signal at the other; if there is any change in the shape the composition has changed: cracks, rust, deformation, getting wet, etc. Similar to a motion detector: For a motion detector every position produces a different echo pattern, but it doesn't have to know what the pattern means: Just that if the pattern changes, something has moved.

• I also did not address attack, or asteroid strike: At some point anything can be overwhelmed by sufficient force. I was only addressing deterioration.

• A little more added to discuss outgassing: I presume we can liberate the gases from asteroids, moon, or other materials. Beyond any structural issues I presume this station is also self-sufficient, or it cannot maintain itself.

Simple polished aluminum in a parabolic arc (or partial dish) can focus enough sunlight to melt, or indeed vaporize, anything. The parabola can be piecewise; meaning an arrangement of flat panels with centers on a parabola, but easily replaced should they be damaged by micrometeorites or debris.

Any heat source is energy; we can use to convert to mechanical energy (Stirling engines, closed-cycle-steam engines) which we can convert to electricity. Remember the electro-splitting of water into H and O: That does not only apply to water; we can liberate gases from other compounds as well. We can melt rocks, turn them into vapor, and using distillation techniques (closely monitored heat so some compounds vaporize while others remain liquid) and centrifugal separation (of liquefied rock, spun hard to separate elements by atomic weight then cooled to retain that separation) we can obtain very pure elements; and remix them to our desire. We can obtain any gases we need to replenish the air and fuels on the station. Solar does it all; and in many ways it is easier in micro-gravity space without any atmosphere. Most benefits of gravity we want we can get with centrifugal force, and control to a fine degree.

posted almost 7 years ago

Amadeus‭

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