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Comment Threads

• Zorro commented on Context is everything
  Well, it's supposedly stable for a couple of thousands of years, and by then we'll probably worrying about ice age anyway. BTW, is the 5000 GT for carbon or for CO2? I thought CO2. And the weight ratio between carbon and CO2 is closer to 3.6 than 4, so for 1000 GT of CO2 you need to bury just 277 GT of carbon. Biochar stability varies depending on particle size and soil conditions, but you are right that it can be reasonably stable for thousands of years. In some cases the half-life is on the order of a couple decades...
• paws4thot commented on Context is everything
  I'm not disagreeing with your base point, but I thought that the ISS was at least an order of magnitude short of having the real estate to grow crops (not a full closed ecosystem, just the physical space for plants) of being able to grow sufficient veg to feed the base crew?...
• Vanzetti commented on Context is everything
  I think you vastly underestimate the complexity of biological systems -- including the fact that around 2-5% of your body weight, when you weigh yourself bare-ass naked, is composed of invisible passengers without whom you will sicken and die. And I think you sacralize* the complexity of biological systems. They are machines with finite number of parts, and one day we will run out of parts we don't understand. If they could build a closed-cycle ecosystem to support the astronauts there it would cut a huge chunk out of their maintenance costs. I don't know how much money was spend...
• Andreas Vox commented on Context is everything
  And I think you sacralize* the complexity of biological systems. They are machines with finite number of parts, and one day we will run out of parts we don't understand. That's an interesting opinion from someone who is halfway through his master of biology. Organisms are not finite machines in the common sense, they are dynamical systems with an infinite number of possible states. The number of parts isn't the problem, the number of possible states is. Plus, biology has the pesky habit of not following a sound systems engineering approach of modular design but creating obscure dependencies from one...
• Hank Roberts commented on Context is everything
  Nature doesn't build the level of biological complexity -- "services" -- that are capable of supporting space-craft-builders except from the bottom up. Look at Mir, or the ISS -- they grow a film of microorganisms, and start working up through mildew and probably mushrooms and slime molds, depending on how much housecleaning got done. A mature long-duration spacecraft is going to be lined with dirt and at least simple plants -- because that's what the surfaces want to be covered by. We interpenetrate. Local populations of various microbiological species are unique to each larger organism. Cut the complexity back --...