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Comment A system like this might be super-habitable for us (Score 2) 87

I think it's amazing that there could be a system with enough comets to block out such a big portion of starlight. It gets my imagination going because when I picture the future of human expansion, I don't see us living on the natural surfaces of planets, putting up with all the ways in which they are ill-suited to our comfort (wrong gravity, wrong color starlight, wrong day/night cycle for our circadian rhythm, wrong atmosphere, wrong temperature range, too much radiation, etc.). I know that people want to address some of these problems with some sort of transforming, and that will make sense on some planets, but most stars will not have eligible ones.

However, most stars will have enough ordinary junk in their orbit that we will be able to manufacture (with self-replicating AI machines) a perfectly awesome and huge spinning habitat that could have a habitable surface area comparable to that of the Earth. The easiest source for the materials for such a habitat are smallish rocks, because it takes so little energy to eject habitat material from a quarry on a rock with such a small gravity well. A colony would simply dispatch an AI-controlled factory that would convert asteroid material into duplicate AI factories, plus fuel and thrusters that get these to other asteroids. Then the factories retool to convert the asteroids into parts for a giant spinning space station, in which the interior light, atmosphere, gravity and temperature are optimized for terrestrial life, while the star-facing exterior is covered with solar panels, and the shady side is a spiky forest of heatsinks. If the orbit is close enough to the star, the panels alone should generate enough energy to power all the systems and more.

It's very 1960's thinking to picture ourselves living on the surfaces of other planets, and yet, even many scientists have not gotten past that obsolete picture. AI technology plus robotics will allow us to thrive even in extrasolar systems that have nothing but perfectly ordinary crap floating in orbit, because perfectly ordinary crap is exactly what we and every important feature of our biosphere are made of.

What's exciting about a system like this is that if there are lots of comets, it means that there's a lot of great crap within arm's reach from which to build a gigantic new home.

Comment Azerbaijan - Land of Fire (Score 1) 57

I always thought that it was weird for a country to advertise on the jerseys of Atletico Madrid, and I thought that "Azerbaijan - Land of Fire" was always a weird motto. I think they were trying to indicate passion, but really, who would want to live in, or even visit, the Land of Fire? Especially now that the fire took out their internet?

If you think I'm kidding, click here.

Comment Why not firefighting quadcopters? (Score 1) 91

I think we all agree that people wearing jetpacks are not going to do much to put out a fire, but how about heavy-lift quadcopters that can haul up pressurized tanks of flame retardant foam? They could make periodic landings to swap out empty tanks and batteries for full ones, and they could actually pump meaningful volumes of foam or gel into the upper floors.

Also, how cool would it be if they would swing a harness attached to a bungee cord to people in windows waiting to be rescued, and have the people do a bungee jump "anchored" to a quadcopter? From skyscraper heights, it would be a lot safer than jumping into air pillows.

Comment Great test for what EULA conditions are binding (Score 2) 418

I don't think there is yet a clear legal precedent about what conditions in EULAs are and aren't legally binding. I want some German person to actually use this software, get sued and take this to Strasbourg, or maybe some higher court. I'm very confident that any sane court would rule that the researcher broke no law in using the software while German, and this is what we need to invalidate many other stupid conditions stipulated in software EULAs.

Comment I find that statement highly problematic (Score 1) 358

...marginalises women and the elderly by implying that something need be simple for an old woman to understand it

I am deeply offended at your quickness to assume that my grandmother is "elderly" or an "old woman". I also don't understand how one can so callously write off all the people whose grandmothers do not self-identify as female. Whoever proposed such an intolerant policy deserves a lifetime ban.

Comment Re:The Nazis Could Have Won (Score 1) 295

To believe that Germany's reason to go to war consisted in exterminating the Jews shows just how brainwashing works over long periods of time.

I suggest you do some reading before resorting to namecalling. Thanks partly to the work mentioned by Fire_Wraith, historical evidence is beginning to accumulate for the race v. race framing of Hitler's motivation for war. Sure, he was optimistic that Germans would prove the strongest race, but it was more important that the struggle of the races is renewed. The Jews played such a central role in Hitler's plans because he thought that they had infiltrated enough of the world's governments that they successfully put a halt to global racial struggle, leaving weak and degenerate races protected by the political artifice of statehood. No doubt this was a totally delusional view of the Jews, which is a prima facie reason to not believe that the Nazis would have held it. But the evidence seems to be stacking up that this is exactly how Hitler saw the situation.

Comment Re:The Nazis Could Have Won (Score 1) 295

The Germans behaved very differently on the Eastern front than they did in France, for example. Most of that can be attributed to expediency. The Eastern front was at the end of incredibly long supply lines, and the scorched earth policy was explicitly aimed to depopulate the areas between the front and the homeland. They thought that if they left any villages unburned, they would fill up with partisans who would sap all the energy from Barbarossa. When Americans invaded Iraq and Afghanistan, they didn't resort to such brutality, but asymmetric warfare from partisans who blend into the population basically undid everything that the US had tried to do, ultimately driving out the Americans and leaving room for ISIS/Taliban. For me, the lesson is that it's a bad idea to try to invade and occupy other countries. You're basically guaranteed to fail.

Comment Call the IT department at a nearby university (Score 1) 508

Universities tend to not keep their computers for more than five years. I've recently that my own university sells computers to a parts scrapper for something like 5c/lb. I've learned this from the scrapper himself, from whom I bought a perfectly boring looking HP workstation with a Xeon e3-1240. I'm using it now and it's a great computer. Anyway, universities are usually not looking to make money from their end-of-life computers. I don't work for a rich college, but even we start scrapping (yes, scrapping - not selling) some computers when they're only four years old. If you caught our IT guy in a good mood and convinced him that you're using these things for an educational purpose, he could very well fill up your truckbed with Dell Optiplexes, and feel like you've done him a favor.

State insitutions sometimes also sell gear in bulk on eBay. Here's is the page for New York State:


I expect you can get a lot of 2010 office computers for $15 a piece. They tend to take out the hard drives, which would be an additional cost, but not a huge one.

Comment Doing something just because it's cool (Score 4, Interesting) 45

I think it's time we admit to ourselves that sometimes, we want scientists to do certain things simply because they're cool. That should count as a perfectly adequate reason, so that we can stop this silly game of pretending that we need to do something cool because we inexplicably started caring a lot about settling some very small and boring scientific question.

I see this a lot when people discuss manned missions to Mars. It's a popular idea, but only because it's cool and full of symbolism we like. It's not because people suddenly became nerds about the history of the Martian regolith, and unmanned missions will simply not adequately satisfy their burning curiosity. Of course, the Mars mission would cost an insane fortune. I'm all for cool things, and humanity is pretty rich, but not that rich. Cloning a mammoth, on the other hand... We might be able to afford that!

Comment For all x, the military wastes millions on x. (Score 1) 154

The military has a huge budget that has to feed and entire ecosystem of contractors and subcontractors. Of course such a system is wasteful, and the scale of military spending is such that it's almost certainly true that the military wastes millions on peanut butter, on underpants, on shampoo, on frying pans and on snake bite kits. Name all the items in your junk drawer, and I bet that the military wastes millions on each of those kinds of things. Wasting millions on satellite capacity doesn't even sound that stupid in comparison. The real shocker would be to find something on which the military actually gets a good deal.

Comment Re:don't look now (Score 1) 35

I take it the point is to use the materials in space to first build something. Only once it's built will people actually come. The reason why our space programs are stuck in first gear is that we don't know how to build things in space from materials that are there. This will change soon, because many of the lessons of automated production techniques on Earth can be applied (with modifications) in space. The problem will be one of sourcing the raw materials from which to manufacture something useful. So that demand is perfectly predictable, and asteroid mining companies are now taking the baby steps they need to take to eventually satisfy that demand.

If you're wondering about what's worth making in space, there are many great ideas. Here is just one: A truly gigantic telescope mirror. It might actually be easy to do, because the factors that make mirror production on Earth so hard are not a problem in space. There is no need to worry about sagging, stress and all these other gravity-related issues. Space-built telescopes could get pretty darn big, The question is: what will they be made of? And the most plausible answer is: materials from asteroids. Like I said, that's just one example.

Comment Small difference between 28 hours and many weeks (Score 1) 20

If the current generation of solar powered drone stays up for more than a day, the next generation might stay up for weeks. Basically, what this shows is that we're pretty close to the threshhold where incoming photovoltaic energy over 24 hours matches the energy needs to keep the thing flying. Just a bit more optimization could mean that the thing takes in more energy than it uses, and then it can basically fly until something wears out. All kinds of interesting things then become possible.

Comment Re:absolute BS (Score 1) 242

I actually think this is great. After all, the patent expires in what, 25 years? I doubt a single engine will be built in that time, but forever afterwards, this idea in the public domain. Consider the alternative, if someone waited to patent this thing until applications were actually ready. Then the patent would prevent competitors from entering the market. But because Boeing hasn't waited, it has basically ensured that nobody will use patent law to put the brakes on innovation when we get around to actually making serious spaceships - which is what this propulsion system is obviously for.

Comment How much infrastructure needs to be there first? (Score 1) 99

Some people think that we should send someone to Mars as soon as possible, even if they can't do much before they return home. Simply leaving a human bootprint would be worth it. Others think that unmanned missions should first build up enough Martian infrastructure to support human "colonists" with a reasonable level of comfort. Only then should people be sent. Where would you put yourself on this continuum? What sort of activities should Martian astronauts be able to do before you would think the expensive trip there was worth it?

"Necessity is the mother of invention" is a silly proverb. "Necessity is the mother of futile dodges" is much nearer the truth. -- Alfred North Whitehead