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Comment Re:Ted Postol very bias opinion. (Score 4, Insightful) 379

Actually, the key thing for them is "cheap". They need to keep costing sub-$1k missiles in the ballpark of these Iron dome systems - the more, the better. They might as well just omit the warheads to save money and increase range. Every $50k shot Israel fires with those systems costs 25 Israelis' annual tax contribution to the IDF. Every $55m system they deploy costs 27.500 Israelis' IDF tax contributions.

Palestinians are poor, but they're not *that* poor that they can't leverage those kind of lopsided financial ratios.

Comment Re:Subject bait (Score 5, Insightful) 379

No, in the case of Iron Dome, that's only PR too. They're shooting $50k+ missiles at $800 rockets. Even after factoring in that Israel's per-capita GDP is 20 times that of Palestine's, that's still a losing proposition, even *if* they had a 100% hit rate (which this article is suggesting it's anything-but) and assuming that you get the launcher, radar, etc for free instead of the actual $55 million per unit. It's in Palestine's best interests that Israel deploy as many of them as possible and try to shoot down every last rocket, because every shekel they spend on Iron Domes and missiles is a shekel they don't spend on jets, tanks, and bombs.

Technology

Texas Town Turns To Treated Sewage For Drinking Water 242

Scientific American reports that Wichita Falls, Texas has taken an unusual step, precipitated by the years-long drought that Texas has faced: it's using treated sewage for drinking water. From the article: To launch what it calls its "Direct Potable Reuse Project," the city pipes water 12 miles from its wastewater treatment plant to this treatment facility where it goes through microfiltration. A pump pulls water through a module filled with fibers that removes most of the impurities. Then it is forced through a semi-permeable membrane that can remove dissolved salts and other contaminants. The process, called reverse osmosis, is used by the U.S. military, in ships and in the manufacture of silicon chips. The water then gets blended with lake water before going through the regular water treatment system. ... At 60 cents per 1,000 gallons, it's far cheaper than any other source of water, [Wichita Falls' public works director Russell] Schreiber said. ... He said there have been few complaints so far. A glass of the finished product, sampled at a downtown restaurant, tasted about average for West Texas.

Comment Re:Need fast-acting yeast (Score 2) 159

I doubt it will be fully legal by 2018. At the state level, I think it's likely more states will decriminalize or even fully legalize, but not all of them. I'll put a guess at: by 2018, it will be fully legal in 15 states, decriminalized in 15, and still criminal to possess in 20 states.

At the federal level, the Single Convention on Narcotic Drugs would complicate legalization efforts, since the Treaty requires signatories to ban marijuana. And the U.S. doesn't want to undermine this treaty, because it uses the treaty to strongarm other countries over things like coca and poppy growing. It's possible the DEA will lower enforcement priority, though, and maybe possible (though imo this is less likely) that Congress will revise the law to reduce sentences from their current levels.

Comment Re:Good. Let's go. (Score 2) 181

Near Earth asteroids contain up to 20% chemically bound water (in the form of hydrated minerals). They don't contain water as water, because at our distance from the Sun it is too hot for water to be retained in a vacuum. To get this water out of the minerals you heat them to typically 200-300C. So stuff the asteroid rock in a closed container, focus enough sunlight on it to reach the required temperature, then have a condenser on the shaded side to turn the vapor back into liquid.

Water has multiple uses in space as propellant, shielding, and for biology. When split to oxygen we can breathe it. Some asteroids also have a large amount of carbon, so you can reform Water + Carbon into Oxygen + Hydrocarbons, which makes an excellent high thrust fuel, but that would be a more advanced application. Simple extraction of water is about as hard as running a distillery for alcohol.

Comment Re:Absurd (Score 1) 181

You don't want one miner to claim all of Ceres or Vesta (the two largest asteroids). What makes sense is to have a "claim size" based on your mining operation and safety. Thus you don't want the next door miner to be landing his ships too close, because the exhaust can kick up rocks or contaminate your equipment. You also don't want to grant a full size mining claim to someone who lands a 1 kg payload with an electric drill. The claim should scale with how much equipment they are landing and the mining rate.

Of course, what makes sense has nothing to do with what Congress might pass, only 1% of their membership have an engineering background.

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