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Comment: Re:The bases have to be built from local material (Score 2) 46

Radiation levels as recorded by Curiosity on the trip were only double that of either LEO or Mars, while definitely not good even without additional shielding you're probably not looking at too much additional cancer risk. Putting significant amounts of radiation shielding around one small area of the craft where the crew is likely to spend most of their time (the cockpit, sleeping quarters?) would easily bring the trip exposure levels down to something a little more reasonable. With ZERO additional shielding (assuming of course they weren't hit by a solar storm) on a round trip to Mars of over 2 and a quarter years Astronauts would only be exposed to 1.01 seiverts (1 sievert lifetime spaceflight exposure is considered acceptable). By far most of that exposure as you noted is from the trip but with even the simplest radiation mitigation measures on Mars (piling dirt on living/sleeping quarters) and a solar storm shelter you could keep your exposure below 1 sievert and stay on Mars for many years. Though without heavy shielding on the transport multiple trips back and fourth for an individual would of course be very risky.

Comment: False Positives (Score 1) 143

Current detection systems already have enough false positives, eating some poppie seed muffins/bread, taking some ibuprofen, etc will trip some tests. This test sounds like it uses much smaller samples so I would imagine it would be far more susceptible. And as others have noted most money has trace amounts of various drugs (cocaine, heroin, morphine, etc) adding a completely innocent vector for false positives. The entire concept of trace drug testing is flawed, testing for significant recent usage MIGHT have some reasoning but these tests looking for usage days, weeks or even months out are foolish, destructive and pointless.

Comment: Re:The bases have to be built from local material (Score 2) 46

I wonder how hard it would be to print or mold glass using in situ materials and maybe some materials from Earth to form glass arches/domes for greenhouses. Silicon is abundant on Mars like any rocky body though I am not sure of the difficulties of extracting any impurities (namely iron oxide) from it. There appear to be entire dunes made of glass on Mars which could be harvested and presumably melted down into glass of some form. Throw in a little lead (preferably molded into the interior of the glass) or just make the glass extra thick and you have pretty good radiation shielding as well as leaded glass about 3" thick is the equivalent of 18 MM thick lead sheet (not sure of straight glasses radiation qualities).

Comment: Re:The bases have to be built from local material (Score 1) 46

From what I understand the radiation dangers have been overstated at least in some cases. Radiation on Mars for example has been shown to be not all that dissimilar from Low Earth Orbit where we have had astronauts for decades with no major ill effects (besides bone loss which isn't radiation related). Now radiation shelters will be necessary since without our thick humid atmosphere most locations would be more susceptible to solar storms and most habitats/living/working quarters should probably be built underground or shielded to limit increased cancer rates but even without that I doubt that I doubt the cancer rates would be too different from here on Earth with exposure to tobacco, lead, asbestos, etc.

Comment: Advantages? (Score 1, Insightful) 164

by Dereck1701 (#49707721) Attached to: Wind Turbines With No Blades

So they're not half as efficient as turbines, meaning you need more than twice as many of them to produce the same power, but they "should" be quite a bit cheaper than turbines due to their simplicity. At best it sounds like they're a draw with current methods, at worst they're a step back. About the only real advantage seems to be that they may prevent the few birds/bats kills by turbines from taking place and may help quell SOME of the NIMBY complaints (noise, blade shadows).

Comment: Re:and yet, the GOP blocks private space. (Score 1) 96

by Dereck1701 (#49706073) Attached to: Russian Rocket Crashes In Siberia

Not quite, there is a good reason why some of our most critical space launches here in the US are being powered by Russian Engines (at least for now) and it isn't all about cost. The NK-33 (RD-180,AJ26-58, RD-180, etc) has an ISP that most US/European rocket scientists didn't even think was technically possible with RP-1 until after the end of the cold war some heard rumors of the stats for the Russian engine that was supposed to power their moon shot and investigated. The Russians simply had a different design method than most other countries, they would quickly slap together and test prototype after prototype knowing they would fail but hoping that with each test they could glean enough information to build it better the next time until they finally had the production rocket. The US and European method was insane amounts of testing and design up front to try to have a production rocket on the first flight. Both methods have their advantages and downsides but both have merit.

Comment: Re:I feel he should've gotten life no parole. (Score 2) 649

"so that they merely never want to go back."

That kind of treatment is a double edged sword, it may make some go straight but it will turn the rest of them into heartless, merciless, vindictive psychopaths that will murder and/or die before they go back. I'm not saying prison should be a tropical resort but it also shouldn't be a training ground for worse criminals.

Comment: Re:satellites (Score 2, Informative) 403

Running out of mono-propellent probably wouldn't be an issue because satellites simply don't attempt those kind of maneuvers without human input (at least I'm pretty sure), while that would definitely be a problem for LEO and Geostationary craft between those two orbits or are further out don't need regular boosts to stay going. And while reaction wheels do go bad pretty quickly (a decade or so) they aren't necessarily needed for a spacecraft to remain "operational". Sure without them they usually can't continue their primary mission but even if the craft has directional solar arrays slow rotation will give likely give them enough power for the satellite to remain in standby mode for decades, possibly a century.

Comment: History repeating itself (Score 1) 515

Sadly based on past statements regarding high speed rail I would imagine that their ticket prices and revenue projections are highly optimistic. The initial numbers said that the project would cost around $36B, cost estimates have since increased to at least $68B. At the same time the projects ridership numbers have been practically disproved, a peer reviewed study suggested a ridership of between 23.4 to 31.1 million where the "official" numbers were 65.5 to 96.5 million. I love the idea of some level of public transport but it needs to be economically viable.

Comment: Re:Last time one was used? (Score 1) 55

by Dereck1701 (#49628019) Attached to: SpaceX Testing Passenger Escape System Tomorrow

Again, any safety system is nice, but its benefits have to be weighted against its costs and risks. Airbags are a good example, some back of the napkin numbers suggest that airbags add somewhere around $15 Billion dollars of cost to US vehicles per year (13 Million new cars, 2 airbags @$600 each). Those airbags save somewhere in the neighborhood of 600-1000 lives per year, assuming those numbers are correct it costs over $19 Million per each saved life. Now I'm all for devoting a few billion towards saving lives but are we getting the best bang for our buck by using airbags or would that money be better used elsewhere?

Comment: Re:Last time one was used? (Score 2) 55

by Dereck1701 (#49626215) Attached to: SpaceX Testing Passenger Escape System Tomorrow

People often make that statement but there is no proof that a LES would have been of use in the Challenger incident. There were no indications of a problem right up until the ET exploded, if a capsule had been on top of the ET stack there is every chance that it could have been crippled/destroyed in the explosion much as the shuttle was. And yes I am well aware that the at least one of the astronauts was alive after the explosion, in the shredded remnants of a useless cockpit. The only way to be reasonably certain of a successful escape would have been to have sensors to detect the issue and activate the escape system before the ET went up, and if such sensors had been available to even the shuttle it would have been possible to have detached from the ET and possibly (though it would have been quite risky) steer the shuttle around for a landing or at least a ditch in the ocean.

Comment: Last time one was used? (Score 3, Informative) 55

by Dereck1701 (#49625699) Attached to: SpaceX Testing Passenger Escape System Tomorrow

I suppose its not a bad thing to have just in case but I don't see the reasoning behind the fixation on it as a design requirement and their ranting about its "importance" in press releases. In almost 300 manned space launches a Launch Escape system has only been of verifiable use in a single incident(Soyuz T-10-1).

Comment: Re:Herbivores dying out? Not cows I hope! (Score 2) 146

by Dereck1701 (#49607581) Attached to: Empty Landscape Looms, If Large Herbivores Continue to Die Out

I'm sure what they are talking about is WILD animal herbivore populations, not domesticated herbivore populations. I think US populations have been decreasing slowly (probably an attempt to force prices up) but globally they're still increasing. I find it highly unlikely that there is any chance of a beef/pork/chicken die out unless purposely done or there is a global natural disaster (meteorite, supervolcano, etc).

Comment: Re:"If you have nothing to hide..." (Score 1) 203

News agencies fact checking government press releases? Not likely. And looking at the video links you provided they're showing the same 2 fires (CVS, Senior Center) and the same cars (Police Cruiser/Van fire, Police cruiser swarmed, black car on fire) over and over with a couple dozen people throwing stuff (pop bottles, rocks, etc) at something (cars/police), less than dozen actually on top/near it destroying and hundreds around it watching/video taping.

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