<story><title>The sci-fi cities of Bezos’s Blue Origin derive from his teacher Gerard O’Neill</title><url>https://www.citylab.com/perspective/2019/05/space-colony-design-jeff-bezos-blue-origin-oneill-colonies/589294/</url></story><parent_chain><item><author>PaulHoule</author><text>Let&amp;#x27;s see...&lt;p&gt;Getting resources from the moon seems out-of-date these days because the moon is far away in terms of energy even if it is close in distance.  Getting resources from asteroids makes more sense.&lt;p&gt;As for Reagan and Thatcher I don&amp;#x27;t see either one as oriented toward growth,  but rather oriented towards a &amp;quot;war against inflation&amp;quot; that involved higher interest rates,  austerity,  and tolerance for a lower rate of GDP growth so long as the pain was felt by the middle and below.  Reagan might have had sharper rhetoric against environmentalism,  but the movement did not collapse until the Clinton years.&lt;p&gt;When I&amp;#x27;ve been envisioning space colonies lately it has been really large structures;  I am fascinated by the idea that you can build a &amp;quot;small ringworld&amp;quot; where the rotation holds in the air with a scale size of a megameter or so,  particularly if you can keep the upper atmosphere cold.&lt;p&gt;The rotation speeds of such a thing are close to orbital velocity and the material requirements are similar to that of a space elevator...  Unless you can construct an orbital-velocity bearing in which case you can build a belt around it to reinforce it.&lt;p&gt;Even then it is hard to build room for any vertical relief into the budget,  no high mountains,  no deep oceans,  probably you get a rather uncomfortable hydrological cycle.&lt;p&gt;It would probably look different from one of those O&amp;#x27;Neil colonies since you&amp;#x27;d have a very blue sky and most of the things that look different from a planet would be far away and would look small.  A lot depends on if the z-axis of the colony is long or short.</text></item></parent_chain><comment><author>headcanon</author><text>&amp;gt; Getting resources from the moon seems out-of-date these days because the moon is far away in terms of energy even if it is close in distance. Getting resources from asteroids makes more sense.&lt;p&gt;You&amp;#x27;re right about raw energy, but one advantage of the moon is that you can build electromagnetic mass drivers that can sling raw material into orbit without affecting the natural orbit of the body (technically you are but only negligibly). For asteroids, you probably have to haul the whole thing back into Earth orbit for it to be useful, and you&amp;#x27;d probably have to use some kind of propellant.&lt;p&gt;Also asteroid missions have much longer timelines if you have to go all the way out to the belt to get them. Less so if you get a near-earth rock, but those missions are pretty complex if trying it in Kerbal Space Program is any indication, and getting it wrong can be catastrophic. Many countries might not take too kindly to people wanting to sling city-destroying rocks around. Moon seems safer in that sense as a first option.&lt;p&gt;The two aren&amp;#x27;t mutually exclusive of course, and there are advantages to both. I imagine we&amp;#x27;ll see both strategies employed in a variety of different ways.</text></comment>
<story><title>The sci-fi cities of Bezos’s Blue Origin derive from his teacher Gerard O’Neill</title><url>https://www.citylab.com/perspective/2019/05/space-colony-design-jeff-bezos-blue-origin-oneill-colonies/589294/</url></story><parent_chain><item><author>PaulHoule</author><text>Let&amp;#x27;s see...&lt;p&gt;Getting resources from the moon seems out-of-date these days because the moon is far away in terms of energy even if it is close in distance.  Getting resources from asteroids makes more sense.&lt;p&gt;As for Reagan and Thatcher I don&amp;#x27;t see either one as oriented toward growth,  but rather oriented towards a &amp;quot;war against inflation&amp;quot; that involved higher interest rates,  austerity,  and tolerance for a lower rate of GDP growth so long as the pain was felt by the middle and below.  Reagan might have had sharper rhetoric against environmentalism,  but the movement did not collapse until the Clinton years.&lt;p&gt;When I&amp;#x27;ve been envisioning space colonies lately it has been really large structures;  I am fascinated by the idea that you can build a &amp;quot;small ringworld&amp;quot; where the rotation holds in the air with a scale size of a megameter or so,  particularly if you can keep the upper atmosphere cold.&lt;p&gt;The rotation speeds of such a thing are close to orbital velocity and the material requirements are similar to that of a space elevator...  Unless you can construct an orbital-velocity bearing in which case you can build a belt around it to reinforce it.&lt;p&gt;Even then it is hard to build room for any vertical relief into the budget,  no high mountains,  no deep oceans,  probably you get a rather uncomfortable hydrological cycle.&lt;p&gt;It would probably look different from one of those O&amp;#x27;Neil colonies since you&amp;#x27;d have a very blue sky and most of the things that look different from a planet would be far away and would look small.  A lot depends on if the z-axis of the colony is long or short.</text></item></parent_chain><comment><author>philwelch</author><text>Ringworlds and orbitals are significantly bigger and harder to build than O’Neill cylinders. O’Neill cylinders are potentially feasible within a century or two; ringworlds and orbitals would take much longer.</text></comment>