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Comment: Re:Some potential, but hardly for a genuine leap (Score 1) 209

by khallow (#48954491) Attached to: NASA Looking At Nuclear Thermal Rockets To Explore the Solar System

The typical fuel to air mass ratio of jet engines is a couple percent, and at highest at the stoichiometric ratio of about 6%. This is small enough that it gets rounded down to zero in a lot of calculations. For something like a turbofan, it is even more air.

Sounds significant to me. Not really sure what the point of most of the rest of your post was since I didn't imply that the original AC's observation was physically incorrect.

You can change the length of a tether to balance forces of things going up and down, to remove the need for engines to provide that force and resorting back to using the Earth as a reaction mass essentially.

I'll have to think about that.

Comment: Re:Two things (Score 1) 471

by ScentCone (#48953649) Attached to: Obama Proposes One-Time Tax On $2 Trillion US Companies Hold Overseas

Obama has no expectation that this will ever pass.

Of course he has no expectation that it will pass. In fact, he'd be horrified if it did! He absolutely does NOT want it to pass, because it's pure theater, designed to allow lefty politicians to say in advertisements that their opponents hate education spending, etc. It's 100% empty, completely disingenuous rhetoric, and should have the bright light of day on it from the beginning.

Comment: Re:So what's the real story here? (Score 1) 121

Disclaimer: That only works if you are white.

Maybe you should use a meme generator for that one?

Or, consider the reality of it. Cops who pull people over while driving unmarked cars are completely used to not being trusted - by anyone, of any color. I have a great relationship with the cops I know, and have never had a bad moment with any I don't. My wife and I are lily white, but I'd never encourage her to pull over for an unmarked car anywhere but in a very populated spot, and ideally in front of the local police station. I do not trust unmarked cars, and there's good reason for that. Great news bit just this morning, where a cop-impersonating douche in a white Crown Vic pulled over (wait for it!) an off duty cop. Good one. He got to flash his badge, and was packing (guy drove off, but was promptly caught and arrested). What do the rest of us get to do?

Meanwhile, back in your race-card-playing department: there's a reason that cops in rougher neighborhoods don't EVER do normal traffic stops in unmarked cars. Cops in marked cruisers get attacked, run over, shot at and otherwise put in peril all the time. And those are guys rolling in plainly marked cars, wearing uniforms. I'll have to look around to see if there are any stats on basic traffic stops in marked vs. unmarked cars in high crime areas. My sense, from talking to people in that line of work, is that it's very rare. Unmarked cars in those areas aren't about traffic citations - they're usually working warrants, drug mules, trafficking, that sort of thing.

In the mean time, if you get the lights on you from an unmarked car, and it doesn't matter what color you are, proceed at the speed limit to the nearest station, or look for a marked car and honk to get their attention (if the unmarked is real, the officer in the marked car will already know what's going on, and will usually join in the stop to help protect the unmarked guy and to make sure anyone seeing the scene understands it's legit).

Comment: Re:Some potential, but hardly for a genuine leap (Score 1) 209

by khallow (#48951981) Attached to: NASA Looking At Nuclear Thermal Rockets To Explore the Solar System

No other mode of transportation has to carry its own reaction mass and throw it away. Not bicycles, cars, trains, ships, submarines, or airplanes.

Actually, jet airplanes do. A significant portion of their thrust comes from the mass of jet fuel, oxidized and ejected out the rear of the jet engine.

Second, every single mode of transportation has reaction mass. For modes that travel on ground, the Earth itself is the reaction mass. For airplanes, it's mostly pushing air. For boats, it's pushing water.

Finally, it makes no sense to talk about transportation modes that don't go where you want them to go. Rockets are horribly inefficient in comparison to cars, but cars can't drive to space. While there are ideas, such as the space tether for making a genuine road to space, they rely on having enough economic activity from Earth to space to make them viable. That market has to be created by a less efficient mode of transportation first.

Even then, space tethers and similar systems need some sort of reaction mass to keep the system from getting pulled down over time by all the payloads coming up. But that need not be provided by a high thrust chemical engine.

Comment: Re:Ion Thruster (Score 1) 209

by khallow (#48951675) Attached to: NASA Looking At Nuclear Thermal Rockets To Explore the Solar System

An Ion thruster (of any variety) is not *remotely* a replacement for a nuclear thermal engine.

Unless of course, you don't need an engine with high thrust to weight which is the case in most space activities. And nuclear thermal won't be used for boosting stuff from Earth's surface, the most important high thrust application. I just don't see your argument.

Comment: Re:"Support" != actually sacrifice for (Score 1) 420

by khallow (#48951477) Attached to: Most Americans Support Government Action On Climate Change
Well, from my point of view, we in the US have done the things you want for decades and are worse off for it. We've "invested" and ended up with "debt", we're tried to plan for the future and ended up with "too big to fail" and an educational system several times more expensive yet less effective than it should be, we have a permanent underclass of unemployed in the name of trying to help them, and losing ground in a lot of areas that the US shouldn't be losing ground. The greedy, self-absorbed rich have done just fine by your "social programs", but what about the people who you actually meant to help?

We did what you want, and it turns out to be shit. So why is digging that hole deeper virtuous?

Comment: Re:So what's the real story here? (Score 5, Insightful) 121

There is simply no way this is actually a good faith attempt to benefit the citizenry here. None.

Just like there is simply no way that you actually post your comments in good faith, right? Because everything that everyone does is always bad, always, right?

You know the saying. When everyone around you is an asshole, you're the asshole.

Of course the cops aren't going to complain when someone so stupid as to walk into their lobby right next to a picture of them and the warrant that's out for their arrest that's posted on the wall makes it easy for them. But the idea here is to simply shut down some scam transactions before they even occur. They don't have to DO anything - just make it clear that people who are uncomfortable with a transaction with stranger are welcome to meet up in the safest place available. Just like they tell you that you any time you think you might be being pulled over by someone who's not a real cop (say, an unmarked car), you can drive to the parking lot of a police station before pulling over. That's been the policy everywhere I've lived for decades.

Your eagerness to make a safe transaction or the serendipitous arrest of a stupid known, predatory criminal a bad thing is truly bizarre. Which of those two things is not in support of "the citizenry?" Which backwards world view are you holding that makes either of those things something nefarious on the part of the local police station? Grow up.

Comment: Re:Um, duh? (Score 1) 216

by HornWumpus (#48948061) Attached to: New Study Says Governments Should Ditch Reliance On Biofuels

Only thing?

Nonsense. To make orbital solar a reasonable solution you have to posit cheap orbital transport.

It could posit room temperature superconductors and solve the same problem with a world wide electric grid and rooftop solar. America could supply it's energy needs with infinite capital and it's roof tops (in gross, not time specific).

Adults understand that energy supply will continue to be from a mix of sources and that there is no magic bullet.

Matter will be damaged in direct proportion to its value.

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