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Comment Re:Stupid design (Score 2) 118

The second one is the device is dropping voltage and consuming power. In standard USB with 500mA at 5V, if the MOSFET takes 1V, that's half a watt of power you're losing in the transistor. (And really, you just use a diode). USB-C with up to 100W, you're looking at losing a lot of power in your reverse protection components.

100% wrong.

The MOSFET is not a diode. Diodes DO cause a 0.6-1V drop. That's why they use a MOSFET instead here in applications where a diode drop is too much. The MOSFET only drops as much as its internal Ron on-resistance allows. For a high-grade MOSFET, that can be in the single milliohms, so it's effectively a dead short. Cheapo MOSFETs are still in the low tens of milliohms. So with 3A of power, that's 1/4W with a crappy 30mohm MOSFET, or 72mW with one with a 8mohm on-resistance. The only reason you'd leave this out if reverse polarity is at all possible is cheapness.

Comment Re:O RLY? (Score 1) 307

Any major manned project at this point is going to involve a lot of robotic probes and preparation.

Yeah, we're already doing that. We've sent robotic probes to the Moon, Mars, and the asteroid belt lately. Have you forgotten about all the hubbub over the bright spots they found on Ceres? We are *not* ignoring the asteroid belt.

But asteroids are a lot easier to get to and from than Mars, precisely because of their lack of gravity and lack of atmosphere.

I disagree. True, Mars has enough of an atmosphere to be a nuisance (because you need reentry shielding, but there's not enough there to be really useful for aerobraking), but it's also significantly closer than the belt. Farther = a longer journey. For a probe, a few extra months might not be that big a deal, but for humans, it is. Mars is already too far as it is (as in, "too long a journey for most people to want to sit in a spacecraft that long", plus the radiation concerns).

A lunar space elevator might be a nice project. But in the end, the moon is a really harsh environment, the resources it has are hard to get at, and it, too, has just too much gravity.

The environment isn't that harsh; it's 3 days away (super-close in celestial terms), and there's no annoying atmosphere, and just enough gravity so that we can operate on it without having to invent all-new methods for every simple little thing. But the gravity is low enough that a lunar space elevator should be quite doable, unlike Earth (where the gravity is way too high so we don't have good materials with enough strength, and we have a thick atmosphere that causes all kinds of problems with such an elevator).

The proximity of moon to earth also means that remotely operated robots are a reasonable alternative to manned exploration.

I disagree entirely. For simple probing around, sure, that'll work OK, but if you want to do any really serious work, you have to have boots on the ground. Remotely-operated vehicles are *not* going to build factories, mines, etc. We do *not* have that kind of technology yet. Some heavy-equipment stuff could definitely be converted to remote-control: dump trucks, shovels, etc. But that'll only work as long as nothing goes wrong. As soon as something breaks or gets stuck, you're going to need some people there to deal with it. So you could definitely get by with a lot less manpower on-site, by operating a lot of vehicles remotely, but you'll still need some. It's just like our UAVs ("drones") used by the US military: the planes are flown remotely, I think even by people stateside, but you still have to have real people on-site in the theater to refuel them, do maintenance work, etc., when they land. It'll be the same for heavy equipment on the Moon.

I still think our primary focus should be exploration of the asteroid belt, first with robotic probes, then towing asteroids into lunar orbits, creating habitats, and finally moving out there.

We're already exploring the asteroid belt. We could stand to do more though. But there's no reason we can't get started building habitats and industrial facilities on the Moon simultaneously. We already know there's a crapload of asteroids out there with valuable ores, so we might as well prepare for using them. And we should definitely be working right away on building the technology for capturing and towing these asteroids.

Comment Re:O RLY? (Score 2) 307

It's much too far away; it's even farther than Mars. It also doesn't have that much mass, and it's all spread out except for Vesta and Ceres. We should be sending probes there, for sure, but we're nowhere near ready to send people there. Even Mars makes more sense than that.

The Moon is right next door, has plenty of material (not sure how usable it is for construction, but from what I remember it is possible to make "lunar concrete" with the regolith), has some water at the poles, has some gravity for manufacturing but not too much so it'll be cheap to launch from there or even build a space elevator (this is entirely possible on the Moon because of the low gravity), and will give us practice in doing stuff offworld without having to endure 6+month transit times.

Comment Re:O RLY? (Score 1) 307

No, if you want to send men all over the solar system, you develop infrastructure that doesn't live in a gravity well. Which, I believe, is what NASA is actually doing.

What are you talking about? I certainly don't see any such infrastructure, just a dumb idea to go straight to Mars without developing any of that infrastructure. That infrastructure you talk about is exactly what I'm advocating with a return to the Moon, though I'm open to other options like asteroid mining to get materials and then building stations at Lagrangian points. But the Moon seems simpler for now since we don't know how to build large stations without launching them piece-by-piece from Earth first, and what I think we need is some offworld manufacturing, which is easier done on the Moon at this time because of 1) proximity, and 2) gravity (we don't know how to manufacture stuff in zero-g; 1/6g is workable, while still massively decreasing launch costs over launching stuff from Earth).

Comment Re: Obligatory (Score 2) 662

Why are we letting them? Because we're stupid, that's why (or, more precisely, North Carolinians are stupid). Republicans tell them what they want to hear about guns, abortion, religion, the "Constitution", etc., and they buy it, and vote for Republicans even though they over and over pass laws to benefit big corporations at the expense of everyone else. In short, Republican voters are stupid.

The Democrat voters aren't much better: about half of them are chomping at the bit to elect Hillary even though she's obviously in the pocket of Goldman Sachs, plus all kinds of other problems (like using a personal email server for Top Secret information, something that any normal government worker or contractor would be thrown in jail immediately for).

So, in short, voters are stupid.

Comment Re:Mars is impossible (Score 4, Interesting) 307

-1 Stupid. Why is this modded "Insightful"? It's dumb.

It's absolutely realistic to have humans living on Mars, or the Moon. It's easy: you build underground.

The problem is, you have to have a lot of technology and capabilities in place to do that. You'll need excavators, and you're not going to do that with one little mission. That's why we need to go back to the Moon, and start working on our construction capabilities there first, before heading all the way to Mars. The Moon is only a few days away, so it's a great place to get started working on this stuff, plus there's still plenty of scientifically interesting stuff to do there. Don't forget how many people would pay a handsome sum to take a vacation on the Moon. Once we have the capabilities of building underground habitats on the Moon, building large ships in space for interplanetary missions, etc., **then** we can head over to Mars and start building there.

As for gravity, we don't know what the long-term effects of 1/3g or 1/6g are on humans. It's surely not as bad as zero-g, which the guys in the ISS put up with. Building on the Moon will help us find this out, and in a safe manner since it's only a few days' journey back home to Earth. Having people spend a month or two at a time on the Moon is probably fairly safe, once we deal with the radiation problem. Mars is more of a problem because it's so far away, so you can't just come home if the low gravity is affecting you. However, it's also double the gravity of the Moon, so it likely won't be such a problem.

Anyway, these things are all challenges which can be overcome, in time. Which is why your post is stupid, because you assert that these challenges can **never** be overcome.

Comment Re:O RLY? (Score 4, Insightful) 307

Sounds like a good analysis. Personally, I don't give a rip about having people walk around on Mars: I think it's far more important to advance technology of reusable rockets, space mining, etc., so I think going back to the Moon makes far more sense.

Think about it this way: we landed men on the Moon over 40 years ago. We haven't been back since. What good did it do us, besides having some neat photos and museum exhibits about our past greatness which we cannot replicate now (without a whole lot of money and effort--we can't just launch a Moon mission next month if we wanted to)? We've actually **lost** the capabilities we had back then: back in the early 70s, we had the ability to send men to the Moon, and we did, several times. Today, we simply don't. Going to Mars will be no different: we'll spend a bunch of money on some big-ass rockets and send a handful of people to Mars, they'll walk around, and then we'll have nothing to show for it besides some photos and rock samples, and we won't be able to easily do it again because it'll be too expensive (because we chose the most expensive method possible because we wanted to do it as quickly as possible).

If we develop technologies more, then trips to other planets and moons will be cheaper. No, a singular trip to Mars will not be cheaper than the slower method of going back to the Moon and developing a lot of tech and capabilities, but **lots** of trips to Mars, to Saturn, to Titan, etc., will be far, far cheaper if we develop the tech now, than just sending singular trips to each of these places.

So the important question is:
Do we want to just send some people to walk around on Mars, and then quit all manned space exploration after that?
Or do we want to be able to send manned missions all over the solar system?

If your answer is the former, then going straight to Mars is the correct choice. If your answer is the latter, then going to the Moon is.

Comment Re:Obligatory (Score 1, Insightful) 662

The problem with conservatives is that they're generally hypocrites. For individuals, they're usually in favor of completely free speech (which is good), but then if you say anything against corporations, they want to pass laws against it, like they have in North Carolina (where it's illegal to expose cruelty to animals on farms, or to soldiers at veterans' centers, or elderly in nursing homes).

Also, conservatives don't seem to mind you talking about things like being gay much, but they'll definitely resist any attempts to allow gay people to get married; conservatives tend to try to push their religious morality on everyone using the law.

Now, as we're seeing, the far-left is getting pretty nutty. But I think most of that is the under-30 crowd. The "normal" liberals over 30 or so don't seem to have these problems, and outside the US wouldn't even be considered very "left" at all. But because the right-wing is so far right in this nation, and full of corporation and money-worshiping religious loons who all follow Prosperity Doctrine, just believing in individual freedom (like to marry who you want, smoke what you want, etc.) and wanting a little bit of government regulation to keep the corporations from going out of control automatically makes you a leftist.

Comment Re:legalism is a crap philosophy. (Score 1) 558

What in the hell are you talking about? I've lived in Virginia for much of my life. This state has the slowest drivers in the nation, and the slowest speed limits in the nation. With a speed limit of 25, you can expect people to drive 20. People here constantly drive 5-10 mph below the posted speed limit. And the speed limits are constantly too low: 2-lane (per side) highways are usually 55mph way out in the boonies, and then step down to 25mph (yes, on a 2-lane highway) in tiny little towns. I guess you've never driven on US-460.
If you're complaining about reckless or speeding drivers in Virginia, you must be in Northern Virginia, which is really a completely different state (and does not include Charlottesville). In the rest of the state, it's worse than any stereotypical retirement community you can find anywhere.

Comment Re:legalism is a crap philosophy. (Score 1) 558

Widening the street will make people want to drive even faster. You need to narrow the street if you want people to drive slower. There have been tons of studies on this.

Even just painting the lines narrower (leaving a big paved shoulder or perhaps bike path) should have a good effect on speeds.

Comment Re:I never heard of Ford (Score 1) 337

The traditional carmakers, as the other poster noted, don't deal directly with customers. Instead, they have a bunch of corrupt dealerships in between, which screw over the customers as much as they can, and are generally not well-liked. So the stealerships get most of the bad reviews and complaints, rather than the carmaker.

So if Ford doesn't like you, they really have no way to prevent a sale of their car to you, because they have no control over the dealerships. But if your local dealership doesn't like you because you trash them in the local press, don't be surprised if they refuse to sell you a car. And Ford won't have any control over that either.

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