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Comment Re: GIGO (Score 2) 80

I agree. Duh, the program is obviously not perfect and screws up sometimes. But I'm amazed by how good it actually is. Even being able to just ballpark it some of the time would be impressive, but the fact that it gets pretty reasonably close most of the time, I find that incredibly impressive.

Someone on my Facebook feed was complaining about how in a washed-out picture of three children the picture guessed only two of them right, but saw one (a young boy) as an adult woman. My response was to crop out just the washed out face, take it out of context, and point out, if you saw this face, not understanding anything about the context, could you guess it? I certainly couldn't have. But that's exactly what the software has to do.

I took a number of pictures of myself in different angles, making different faces, etc, and its range on age guesses was only 3 years. My brother-in-law managed to get a 20-year difference in guesses by making faces, but I couldn't manage it, and neither could most people I know who tried. Again, computationally, it's very impressive.

Comment Re: Transphobic assholes (Score 1) 161

And how exactly do you know what her DNA is? There are XX men and XY women.

And seriously, of all of the stupid measures of who someone is, DNA has to take the cake. "Okay, okay, this Stephen Hawking guy seems to be smart, but that doesn't matter, what does his DNA say? Does his DNA say he's smart? If not then I don't care what he has to say."

Comment Re:Popular support (Score 1) 179

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:Popular support (Score 2) 179

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) 179

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:usually the complaints are for too much politic (Score 3, Informative) 179

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) 286

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) 480

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 Re:Point proved (Score 0) 301

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) 301

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.

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