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Comment Re:W.C. Fields Does Politics (Score 1) 6

What could they possibly reveal about Trump that is worse than what everyone already knows about him? He's widely known to be Mafia connected, and he's made statements at Republican primary TV debates about bribing politicians.

(And add to that the fact that any "scandal" is likely to be another thing the establishment cares about and nobody else does.)

I doubt, at this point, even dead girl/live boy would do it.

Comment Re:Duh (Score 1) 386

I think you missed the simple fact that everything was working fine before, without cramming everything in the init process.

Has everything been crammed into the init process? In what may have been a bad PR move, the systemd people use "systemd" both to refer to the init process and to their whole suite of daemons, most of which run as processes separate from process 1, so "systemd does XXX" doesn't necessarily mean "XXX has been crammed into the init process".

Comment Re:Holy crap ... (Score 1) 52

The security difference between chip-and-signature and chip-and-PIN matters in only one case, and that is if your physical card is stolen from your wallet. Skimmers, data breaches, shoulder-surfing, all the hacking attacks won't yield the secret key inside the chip, preventing it from being counterfeited. If you don't like the security of your chip-and-signature card because you're afraid your card might be stolen, ask your bank to issue you a chip-and-PIN card instead. If your bank won't, there are plenty of other banks who will, and who will be grateful for your business.

Visa and the retailers originally figured U.S. customers would prefer chip-and-signature because it makes selling things "easy". But that's a pretty stupid attitude, because lots of people (including you and me) are wary about identity theft. Customers need to complain to their banks so that they learn we'd rather have PINs than signatures.

Overall credit card security will still remain terrible for a long time to come because static mag stripes still exist, and online card-not-present transactions still use static authentication data like CVV2 codes. What really needs to happen to actually improve security is that mag stripes and static numbers like CVV2 need to be flat-out outlawed. The recent "liability shift" is the opening salvo in the conversion, but we're probably still a decade away from actual security.

Comment Re:Not too hard (Score 1) 52

The EMV chips have been compromised for years. Typically it only takes a couple of weeks to break the latest version. The reason chip-and-PIN sounds so good is the European rules changes that accompanied it: if the transaction was done using chip-and-PIN then it's presumed valid and it's up to the cardholder to prove otherwise which is extremely difficult short of having absolute undeniable proof that you were physically at a different location at the time of the transaction (eg. timestamped video showing you at that other location at that time). So if the EMV chip in your card is compromised and cloned, the fraudulent transactions run up on the fake card are presumed not fraudulent and attempts to dispute them as fraudulent will be denied absent you having extraordinary proof. That skews the fraud statistics considerably.

The reason European cardholders don't raise a fuss about this is that 95+% of card fraud these days is done online using card-not-present transactions where chip-and-PIN isn't a factor. That won't change whether the US adopts chipped cards or not.

Comment Re:Space-based Economy (Score 2) 262

As usual, "pop science" news overstated the case. We know that there's ppm quantities of water in most lunar regolith, but that's not what people usually talk about. There's also a good degree of confidence that there's a lot of *hydroxyl* group in a lot of places on the moon. But the connection between that and the group being specifically water is much weaker - and many missions sent to detect water in likely areas have failed. The best evidence for water have come from Chandrayaan and LRO, examining craters that were considered likely to find ice. They have both failed to find "slabs" of ice in the crater, but found evidence for ice grains in the regolith - about 5% according to LRO. On Earth that would be considered dry soil, but it's something at least.

Of course, if you're constraining yourself to such craters, you're really constraining where you can go. On the general lunar surface, the sun bakes water out of the regolith.

Iron, aluminum, and titanium are very useful for making things

They're all tightly locked up as oxides, without the raw materials that we use to refine them on Earth being available. There are however tiny grains of raw iron in the regolith, so there is some potential to comb it out magnetically. Still, asteroids present by far better resource options in much greater concentrations.

There really is just no reason to do your work in a gravity well as deep as the moon's, and then have to break out of it, when you can just mine NEOs. Yes, it's "half the gravity of Mars", but it's vastly more than asteroids. Rockets with a couple thousand spare m/s delta-V don't just grow on lunar trees.

Comment Re:Space-based Economy (Score 1) 262

The moon's surface is kind of boring, as far as geology goes. Aluminum oxide, titanium oxide, iron oxide, silicon dioxide... by and large it's stuff that's really common on Earth. And not much of the common stuff that's super-useful, like water. And really, it's way more of a gravity well than is ideal to have.

Comment Re:Cost of access is key. (Score 1) 262

No no, we can get much more than a 1-2% improvement in chemical rocket performance. The issue is that for our needs thusfar (large objects to LEO and GEO, small objects further out with long transit times and gravity assists or ion propulsion), H2/O2 has been fine and it's not been worth all of the headaches of more energy dense fuel mixtures, like Li-(LF2|FLOX|OF2)-LH2 triprop. But we can indeed get a 25% improvement in ISP if we're willing to work with very hazardous, toxic chemicals (at least the resultant LiF isn't as toxic as F2!). It was already done in a lab-scale development back in the late 1960s. And let's not kid ourself, NASA has indeed launched successful missions using toxic, corrosive and dangerous chemicals as propellants. But this would be a new upper bound in this regard. I doubt they'd ever use a propellant like that on a lower stage, but for an upper stage or a return stage... it's a possibility.

Without invoking significant toxicity we can improve the picture somewhat. Burning the lithium with O2 (and of course H2 for exhaust flow reasons) is also a very high energy propellant, but it still means working with metallic lithium in some form or another (liquid, hybrid, slurry, cryosolid, etc), which most people would really like to avoid. But it is possible to do.

A small boost to H2/O2 can be made with aluminum - it only boosts the Isp a few percent (I believe about 4%-ish, though I'd have to double check), but it also gives a nice secondary bonus of really increasing your propellant density. Aluminum is neither dangerous nor toxic, but burning it with the H2/O2, and in a reliable manner, hasn't been tackled yet.

Boron is another high-energy compound one can use. As is beryllium (Be-F2-H2 is even more powerful than Li-F2-H2 by a small margin), but it's hugely expensive and extremely toxic in dust form.

Beyond all of the "familiar" stuff there's a lot of research on more exotic compounds with strained chemical bonds which remain in a metastable state until burned; there's way too many such compounds to list here. But at present they all generally suffer from either production cost issues or problematic instabilities.

Oh, and you can also improve performance by increasing the chamber pressure. That said, it's rather modest - if I recall a doubling of chamber pressure is usually on the order of a 7% ISP boost. But it does mean that advances in material technologies can translate to advances in rocket ISP. And there's also a wide range of other modifications to engine design that could boost rocket ISP to lesser extents.

Comment Re:Cost of access is key. (Score 1) 262

Staging works pretty well to get around the energy density problem, at least early on.. though the rocket equation starts getting pretty tyrranical when it comes to returns from other planetary bodies. It's really hard to conceive of a manned Mars mission with return that doesn't involve at least the return ascent stage being fueled by one of the following:

1) In-situ propellant production
2) Extreme-ISP chemical propellant
3) Nuclear thermal

You can't rely on ion propulsion (even higher power variants like VASIMR) to get you off the ground. Nuclear thermal (1) should work (NERVA showed promise), but the development costs will be huge and it'd face massive public opposition, having that much nuclear fuel on a single craft. It also puts a rather large minimum size for your ascent stage - fission doesn't scale down well, and even as big as it was NERVA only had a thrust to weight ratio of 3 to 4. And the mass of that large, heavy ascent stage imposes significant mass penalties on your earlier stages, partially negating the benefit of that 800-1100 sec ISP.

For more advanced chemicals (2), there's lots of theoretical stuff, but with stuff that we could do today for a practical cost, it'd probably pretty much have to be some variant of lithium/fluorine/hydrogen triprop. The oxidizer could be LF, FLOX, OF2, or a couple other possibilities... but if you want an ISP(vac) from chemical propellants in 500-550 range and good density, that's pretty much what you have to do (yes, the LM and CSM used toxic, corrosive, dangerous propellants too, and NASA managed fine, but these are even worse). And even still, 500-550 sec is low enough that you'd probably still want some sort of ion "tug" cycler to move you between LEO and LMO, with your fuel only used for ascent.

If you don't want to or can't do either of those two options (#2 and #3), you're pretty much stuck with in-situ production (unless you want to have to launch a LOT of tonnage into orbit!) Which is why that's SpaceX's focus... it probably is the best option. Still, though, it's a challenge and a risk, no question.

Comment Re:If we're going systemd, we should go full throt (Score 1) 386

Except when it doesn't and since it swallows stderr

A sane background/daemon process launcher sends stdout and stderr somewhere where it gets logged. Are you saying systemd just sends the standard output and error of stuff it launches to /dev/null, or that it sends them somewhere that's not easy to process? (Launchd sends them to the Apple System Log mechanism, which, yes, does have a binary log database, but ASL also sends stuff, including the stdout/stderr from launchd-launched processes, to the Boring Old Text File /var/log/system.log.)

Comment Re:Affirmative Action won't take us to Mars. (Score 1) 262

I think his job is more "ticking large numbers of people off". For example, he was one of the leaders behind the "Pluto, Eris, Ceres, etc aren't planets" movement - he had references to Pluto being a planet removed from the Hayden Planetarium years before the IAU vote. He's not exactly popular among those who felt that hydrostatic equilibrium was the relevant constraint and that the "cleared the neighborhood" definition is fundamentally flawed.

Comment Re:The guy aint no Sagan... (Score 1) 262

Which is silly, because the Apollo mission was primarily oriented around the physics of getting a bunch of large mammals into space, keeping them alive on the way to the moon, landing them on the moon, keeping them alive down there while they explore, and then doing all of that in reverse. If they hadn't brought a single rock back the total change to the mission cost would have been almost unnoticeable.

Furthermore, who's focused on mining the moon? Most mining proposals focus on mining NEOs. It's way easier to get material from a NEO to Earth aerocapture. You could do it with a coilgun with no expenditure of consumables, again and again for years on end. They're also far more rich in interesting materials - much better than the best mines on Earth, and with no overburden.

Comment Re:If we're going systemd, we should go full throt (Score 1) 386

If as a result the Linux community grows closer together and focuses more on consistency I'm all for the move to systemd - even if that moves Linux away from the rest of the unixes due to loss of posix compliance.

Not that systemd affects POSIX compliance (and not that Linux is certified as POSIX-compliant; I haven't found it to be significantly worse than any other UN*X in terms of "annoyingly different from everybody else" - frankly, if there isn't at least one thing your UN*X-family OS does annoyingly differently from all the other UN*X-family OSes, it can't really call itself a UN*X :-)).

Make it right before you make it faster.