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Comment: Re:Popular support (Score 1) 121

by Rei (#49604743) Attached to: NASA Gets Its Marching Orders: Look Up! Look Out!

I don't think NASA needs to make the fictional heroes; I think every piece of sci-fi that comes out helps inspire the next generation. I guarantee you that there's tons kids and young teens who saw, say, Gravity and think that's what it is to work at NASA and have set that as their aspiration. "Astronaut" is usually in the top 10 of what kids want to be when they grow up.

More than anything else, I see the main point of having astronauts is just to inspire kids. Just knowing that there's people going up there is enough - they don't need ot be doing big stunts that cost hundreds of billions of dollars to put a footprint on a distant body; they simply need to be twirling around in zero G in LEO.

Comment: Re:2kW isn't enough power for a home (Score 1) 499

by swb (#49604739) Attached to: Tesla Announces Home Battery System

Why would you do that? Every single one of those things has an off switch. In all but extraordinarily rare cases, use of every one of those things is discretionary. You don't need to rewire your panel in order to keep the house running during quite a long power outage. Just don't use heavy draw appliances. If you are affluent enough to buy one or more of these battery packs in the first place, you can certainly afford to buy a few paper plates and an extra pair of underwear, if it comes to that.

What happens when you're not home and the base load goes away and the battery kicks in and your draw exceeds your output capacity? Maybe if you're actually home you can turn off anything high load or that's discretionary, but if you're not you'll overload the battery and I'm assuming it will either current-limit itself via voltage drop or just plain shut off output, which is probably the sanest/safest to prevent damage.

What would be nice would be a smart panel that kept track of the load on all the breaker legs, each of which could be assigned a priority level. Loads could be assigned "always off on battery", "switchable", "always on" and the system could disable switchable loads to ensure that there was sufficient power for always on loads, and the priority setting could be used to switch off "always on" loads so that the highest priority loads could keep running as battery levels dropped.

Regardless of your individual situation, it's a gamechanging device for the vast majority of the world.

I'm not sure how gamechanging it really is.

Comment: Re:Popular support (Score 1) 121

by Rei (#49604707) Attached to: NASA Gets Its Marching Orders: Look Up! Look Out!

How many current astronauts can you name?
How many current astronauts can anyone here name off the top of their head?

The time of astronauts as heroes has passed. Far, far more people today do care about MESSENGER and New Horizons than they do about what astronauts are doing in space. They get more coverage in the popular press too. MESSENGER hasn't been a big public eye-catcher (except briefly when it crashed) but there was lots of attention about Rosetta, MERs, MSL, Cassini periodically (for example, the geysers of Enceladus, the Huygens landing, etc), and you better believe New Horizons is going to get a lot of coverage when it does its Pluto flyby (the public has a lot of interest in Pluto, more than in a long time due to the "demotion" controversy)

Yes, the percentage of Americans who read about these sort of things when they come up in the news (let alone follow them in depth) is probably in the 10-20% range. But so? How many specific sub-programs in the Social Security Administration or Internal Revenue Service can you name? NASA still captures the public imagination in a way that no other part of the federal government does. It doesn't take a moon landing to do that.

Comment: Re:Did a paid shill write this summary? (Score 1) 121

by Rei (#49604651) Attached to: NASA Gets Its Marching Orders: Look Up! Look Out!

It's about time someone defunded this utterly ridiculous and transparent scam.

Indeed, it's about time they defund SLS/Orion!

Don't get me wrong, NASA should be in the launch systems business. In the revolutionary launch systems business. Government programs are supposed to exist to do the important thing that private industry is unwilling or unable to do - in the science field this means things like such as science without immediate commercial applications, very expensive basic research, etc. There is no shortage of private companies now competing over the launch market, and indeed even for the heavy launch market. It's no longer some sort of monopolistic scenario.

NASA needs to be working on rocketry techs that are seen as too much cost / too much of a long shot for private industry to try - that is, until someone else (such as NASA) can prove them. Metstable fuels, nuclear-steam rockets, liquid airbreathing rockets, scramjets, solar sails, magnetic sails, fission sails, advanced ion propulsion technologies, fission fragment rockets, ballistic launch, launch loops, antimatter-initiated microfission / microfusion rockets, nuclear saltwater rockets, nuclear pulse propulsion, and on and on, plus advanced non-propulsion techs for landing, transit, sustaining a base/colony, new communications technologies, advanced robotic systems, etc - with all exact schematics, production instructions, consultations with the developers to serious parties, etc made available at no charge. I'm also of the opinion that NASA should produce and make available at low cost to private space companies and researchers the sort of large-scale analysis and test facilities whose capital costs would break a startup.

Basically, they need to be filling in the gaps in advancing space technology, not trying to do everything, even those things that other parties are more than happy to do on their own with their own money.

Comment: Re:He's also an interesting candidate for this (Score 1) 246

by swb (#49604635) Attached to: Bernie Sanders, Presidential Candidate and H-1B Skeptic

What about actual markets in predominantly rural and agricultural economies?

People show up to buy and sell their commodities, nobody has a monopoly on supply, no purchaser is big enough to swing prices, information asymmetry is low -- you can walk around the market and check on the quality of commodities, determine prices and supply levels, etc.

Comment: What about hacking the system for drugs? (Score 1) 31

by swb (#49604595) Attached to: Hacking the US Prescription System

I always thought we'd hear about the prescription system hacked for drugs, not for personal information.

There's a ton of pharmacies out there, how do "they" know where to send shipments? How do "they" verify that a shipment is going to an actual pharmacy and not a shell entity, especially if its CVS store #1887?

What about actual prescriptions? Many are electronically transmitted to the pharmacy. The schedule II ones (at least when I've been given oxycodone) are printed on paper, but how is that data correlated with the prescribing doctor as legitimate?

Is every order printed out on paper and cross checked by somebody?

Comment: Re:usually the complaints are for too much politic (Score 1) 121

by Rei (#49604579) Attached to: NASA Gets Its Marching Orders: Look Up! Look Out!

That might be true if this was some sort of dispassionate commentary on the bill. But it's not, it's a ringing endorsement of a highly partisan bill. Surely you see the difference.

For those who are serious, here's the Planetary Society's commentary, with a link to an indepth but nonpartisan analysis at SpacePolicyOnline. The Planetary Society is very happy with the planetary science numbers, not happy with the earth science numbers, and couldn't seem to care less about the funding for SLS/Orion.

Comment: Re:More religious whackjobs (Score 1) 219

by Rei (#49602743) Attached to: Native Hawaiian Panel Withdraws Support For World's Largest Telescope

It's the same reason why many of the oppose geothermal power, keeping Hawaii reliant on burning oil for most of its electricity. Also why there's opposition to even trying to redirect lava flows as most countries do when their people are threatened (with a number of successful redirects having been achieved).

Apparently Pele wants people to be ignorant of the cosmos, to destroy the climate, and to lose their dearest possessions without putting up a fight.

Comment: Re:This again? (Score 1) 416

by Rei (#49599695) Attached to: New Test Supports NASA's Controversial EM Drive

I've seen plenty of work on accelerator-drive heavy isotope reactors but nothing for light isotope reactors like lithium. Accelerator driven heavy isotope reactors still deal with many of the problems of conventional fission reactors - they're greatly improved in many regards, but still problematic (you still have some plutonium, you still have some fuel availability/cost limitations, you still have some long-lived waste, you still have some harder to shield radiation, you still have a wide range of daughter products making corrosion control more challenging, etc - just not to the degree of a regular fission reactor). A light isotope reactor using lithium would virtually eliminate all of these problems. And it has a higher burnup ratio, which is of course critical for space uses.

And while everything I've seen about past improvements in accelerator efficiencies and spallation process improvements, and what's being worked on now, suggests no limit any time soon on neutron production efficiencies - at least that's how it looks from the papers I've read. Plus, even if efficiencies couldn't be improved any further (there's not that much further one needs to go), one could hybridize a heavy isotope and light isotope reactor, using a heavy isotope target as a neutron multiplier to bombard the lithium. You'd require significantly reduced quantities of heavy isotopes relative to a pure heavy isotope reactor, and most of the energy from the lithium side could be as mentioned captured without Carnot losses, which is a big bonus. Any non-thermalized neutrons of sufficient energy would produce tritium as a byproduct, which of course would be a value-added product - in fact, given that the tritium-breeding reaction with 7Li and a high energy neutron yields a lower-energy neutron, the thermalization could potentially be done via tritium breeding in the first place. And tritium is a valuable product whether one has interest in D-T fusion or not.

I just think it's weird that I've not come across any work on a lithium-based accelerator-driven spallation reactor, and was just wondering if there's a reason for that. It certainly looks appealing to my non-expert eyes. I mean, it looks even cleaner and more fuel-available than D-T fusion, and looks closer to being viable on a full-system perspective. Versus accelerator-driven heavy isotope fission you get less power per neutron (about a quarter as much), of course, even accounting for Carnot losses in the former - but that's not what matters. Cost is what matters, and if you're eliminating the use of super-expensive fuel, not producing any costly-to-manage waste, have no incident radiation, no proliferation concerns, etc, you're completely changing the cost picture - without even considering the possible joint production of saleable tritium.

Comment: How about sane warnings? (Score 1) 308

by mcrbids (#49598809) Attached to: Mozilla Begins To Move Towards HTTPS-Only Web

As it is now, you are not notified of security issues when you have no security whatsoever. HTTP sites should be given a dire, red warning because they represent the least secure position online. An SSL site with an expired certificate is far more desirable than an HTTP website.

Green should represent proper SSL certificates, as it does now.

But there's one more problem with SSL/HTTPS sites that nobody talks about: the fake SSL certificate. Your browser *probably* trust a multitude of SSL certificate vendors, and *any* of them can issue a certificate for *any* domain.

So there are literally hundreds of SSL certificate vendors that could issue a cert for google.com or whatever, and you wouldn't know. If the NSA offered a bit of $$ to a commonly trusted (but otherwise unheard of) certificate vendor to issue a few certificates to be used discreetly....

See the problem?

If I go to Thawte or RapidSSL to get a cert, I should have the ability to publish my vendor of choice, and nobody else's certificates should be considered trustworthy. Similarly, I should be able to publish revoked certificates the same way.

Why hasn't this already been done?

Comment: Re:Point proved (Score 0) 277

I own a 2001 Honda Insight hybrid modified to be a PHEV and plugged in nightly to charge on geothermal power.... and a Ford Ranger ;) The "why" is obvious, because I have regular needs to carry big heavy things, now that I own land in the countryside. Back when I had no such need... I didn't own any such vehicle.

I guess it's hard for him to imagine that a woman would have a need to carry large and/or heavy items?

Comment: Re:this is science, so you have to ask... (Score 4, Informative) 277

And the crazy thing is, they did consult with male colleagues before publishing. The reviewer just assumed that because two women submitted a paper with a conclusion that he disagreed with, that it's specifically because they're women "making ideologically biased assumptions" who refuse to talk to men.

Comment: Re:This again? (Score 0) 416

by Rei (#49596849) Attached to: New Test Supports NASA's Controversial EM Drive

Oh hey, since we've got (assumedly) a lot of physics nerds on this thread, and because my mind hasn't suddenly stopped being curious about random topics even though I grew old: here's one of my more recent things that left me with unanswered questions:

One of the commonly cited tritium-generating reactions is 7Li+n(>2.466 MeV) -> 4He + 3H. But is 7Li not also capable of transmutation to 8Li via slow neutron capture? If so would that not yield a 16.004 MeV beta to 8Be, and then immediately into 2 alphas with an additional energy of 0.092 MeV? If so, is there not potential for a future nuclear reactor? Spallation currently yields neutrons for about 25MeV each. If one could cut that in half or less - which I don't see any laws of physics in the way, just improvements in accelerator efficiencies and the spallation process - could this not yield a net positive, using direct deceleration/capture of the beta to generate power without having to suffer Carnot losses? And if so, would that not be a very desireable reactor - nonproliferative, abundant fuel, harmless waste, high ratio of fuel to energy conversion, direct spacecraft thrust possibilities, etc? Or am I totally off base here?

If Machiavelli were a hacker, he'd have worked for the CSSG. -- Phil Lapsley

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