Continuing from last week’s topic of interstellar travel and moving on to the more science based topic of life support meaning what are all the things needed to consider to keep humans alive for long times while moving between solar systems. There are several problems with living outside the nursery that is Earth, and here are some of them as well as some solutions from fiction, real life (mostly the international space station) or fresh out of my head.
Obviously we cannot live without oxygen. A human being will begin to die after four minutes without oxygen, so that seems like a good place to start. The problem with pure oxygen is that it’s highly flammable and so it shouldn’t be kept near anything with flames or sparks like oh, say an engine. So usually oxygen meant for breathing (outside of hospitals I mean) isn’t stored in pure oxygen form but rather it’s mostly nitrogen just like the air in Earth’s atmosphere. We breathe out carbon dioxide so that needs to be managed as well. On the international space station they’ve handled the matter in the manner described in this article; basically they’re using the water they have on board to get oxygen.
Although oxygen and hydrogen (the main ingredients of water) are some of the most common elements in the universe, water itself is very uncommon. So far – as far as I know – Earth is the only place we have found water on. Mars may have had water in the past and it may still have some underneath the crust, but there is no conclusive data as of yet. This means mostly, that water would need to be extracted from the sewage treatment.
We can do well without waste, but we do produce it several times a day. Any extended stay in space needs to solve the problem of waste management which is not an easy one, let me tell you. In a previous life (not a woo-woo previous life, but you know, figuratively) I was a maritime student and I’m here to let you know that being in the middle of an ocean with the septic tank broken is no fun at all. And that’s only a couple of week away from port. What if the trip took longer?
Time is obviously a problem with regards to interstellar travel. Human lifespans are rather short and the distances rather long. It’s completely conceivable that even with near-light-speed technologies the that leaves Earth and the crew that arrives to the destination do not have a single member in common. The method used to combat this is most usually either stasis- or cryo-chambers. Very occasionally someone will use multi-generational trips, which present another problem; genetics. At one point before actual human history began we were basically an endangered species so humans mostly are very inbred (although not quite as inbred as some religious texts would have us believe) and even if the multigenerational trip were to start off with several thousand people who were chosen specifically to be as far away from each other genetically speaking as possible, it would still narrow Have I missed something?