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Humans are progressing slowly toward megaprojrcts in the past two centuries, so perhaps they will be spectacular by the year 2999?
Quite soon, we can send robot probes to many asteroids to separate elements and useful compounds from what the probe finds there. When and, if later a mega project in our solar system is desired, the materials can be assembled from the stock piles on many asteroids. The delta v is much less than obtaining these materials from Earth's surface and delivery often takes less than a year even by cheapest transportation. A year delay is a minor problem for a mega project, if we plan ahead. The only downside I think of, is there is no return on the investment in asteroid mining the first century, or however long it is until a mega project is willing to pay for the material. Please suggest ways to make this practical, soon, as we may not have until 2999 to establish extensive off Earth human habitats = Earth may be back in the dark ages much sooner. We won't build megaprojects, if the cost is too high. I'm reminded of the 19th century railroads that often produced no profit until the 20th century, but today's technology would be decades behind if we had not done railroads nor the interstate highway system.
3 個解答
- adavielLv 77 年前
I can't suggest anything much better than Gerard O'Neill etc. did, except that we probably have better computers than was envisaged and as you suggest can perhaps use more robots and less guys in spacesuits, which makes things a lot simpler without all the life support infrastructure to house and feed people not just in colony structures but everywhere anyone is working.
Right now, we're trapped. Western civilization will crash sometime in the next 200 years unless it can switch to a more sustainable model without the current exponential propulation growth. Getting resources from space will not help, much, because part of the problem is sinks not sources - we will run out of places to put our junk sooner than we will run out of materials to make more junk. (I don't mean just landfills, I mean the whole business of flushing stuff down the toilet to the oceans, agricultural runoff, pollutant buildup in the food chain etc. that can't be solved with a bulldozer)
I doubt it will be economical anytime soon to ship a lot of material offplanet, and the wisdom of assembling cars and washing machines in orbit and aerodropping them to earth is a bit dubious.
Sending information is cheap, and colonizing space as insurance agains some planetwide catastrophe seems like a good species survival strategy.
- 匿名7 年前
NAUGHTY NAUGHTY NAUGHTY TRACY
mis use of Y Q & A
- 匿名7 年前
why can i see planets go around other stars from here on earth with just my naked eyes