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Comment: Re:no we can't (Score 2) 74 74

I find this an interesting statement. Running the numbers, I find that you'd have to be using a rocket burning something rather better than H2/O2 (we're talking Isp >500 just to reach escape speed, much less to reach the target rock) to allow two launches of a delta-IV heavy.

Huh?

The fact that a Delta-IV Heavy has a LEO payload of over 27 tonnes is a fact. You don't need to "run the numbers". As for the kick stage, I didn't specify a propulsion system - for all we care (since we haven't established a timeframe), it could be an ion drive and not even take a rocket so large as a Delta IV-Heavy.

Meanwhile, the Falcon Heavy is to make its first launch this year, with double the payload of a Delta IV-Heavy. And as was mentioned, the Tsar Bomba was not optimized to be as lightweight as possible.

And this entirely ignores that noone actually has a Tsar Bomba sized nuke available to be detonated.

Oh, and you didn't allow for a backup

It's almost as if I didn't add "with enough advance warning" for that scenario and leave what "enough advance warning" is unspecified. But if there's another rock the size of the Chicxulub impactor out there and we don't see it until the last second, we deserve to get hit - we're no longer talking about a 50 meter spec (Tunguska-sized), rather a rock with a cross section 30% bigger than the island of Manhattan. We're talking about an impact of a scale that happens once every hundred million years or so.

Comment: OMG - matti makkonen .fi sms pioneer dead (Score 0) 31 31

A more appopriate version of the BBC's article:

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OMG - matti makkonen .fi sms pioneer dead!!!
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WTF - mm just died @63! #txtpioneerdeath was father of sms & dvlped idea of txt msg with phones. @2012 msged BBC that txt would be here "4EVR".
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shoutout 2 Nokia for spreading sms w/Nokia 2010. thought txt good 4 language. was btw mng. director of Finnet ltd and "grand old man" & rly obsessed with tech.
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OMFG people!

Comment: Re:no we can't (Score 2) 74 74

It is not only possible, but the easiest option, to "blow them up Armageddon style" (minus the drilling and the like). There's a lot of simulation work going on right now and the results have been consistently encouraging that even a small nuclear weapon could obliterate quite a large asteroid into little fragments that won't re-coalesce, while simultaneously kicking them out of their current orbit. A few years ago they were just doing 2d calcs, now they've gotten full 3d runs.

Think for a second about what nuclear weapons can do on Earth. Here's the crater of a 100kt nuclear weapon test. It's 100 meters deep and 320 meters wide. You could nearly fit a sizeable asteroid like Itokawa inside the hole. And that thing had Earth's intense gravity field working against it and was only 1/10th the size of weapons being considered here. In space you don't need to "blast out" debris with great force like on Earth, you merely need to give it a fractional meter-per-second kick and it's no longer gravitationally bound. And the ability of a nuclear shockwave to shatter rock is almost unthinkably powerful - just ignoring that many if not most asteroids are rubble piles and thus come already pre-shattered. Look at the "rubble chimneys" kicked up by even small nuclear blasts several kilometers underground (in rock compressed by Earth's gravity). Or the size of the underground cavity created by the wimpy 3kT Gnome blast - 28000 cubic meters. Just ignoring that it had to do that, again, working against Earth's compression deep underground, if you scale that up to a 1MT warhead the cavity would be the size of Itokawa itself.

You of course don't have to destroy an asteroid if you don't want to - nuclear weapons can also gently kick them off their path. Again, you're depositing energy in the form of X-rays into the surface of the asteroid on one side. If it's a tremendous amount of energy, you create a powerful shattering shockwave moving throughout the body of the asteroid. If it's lesser, however, you're simply creating a broad planar gas/plasma/dust jet across the asteroid, turning that whole side into one gigantic thruster that will keep pushing and kicking off matter until it cools down.

The last detail is that nuclear weapons are just so simple of a solution. There's no elaborate spacecraft design and testing program needed - you have an already extant, already-built device which is designed to endure launch G-forces / vibrations and tolerate the vacuum of space, and you simply need to get it "near" your target - the sort of navigation that pretty much every space mission we've launched in the past several decades has managed. In terms of mission design simplicity, pretty much nothing except kinetic impactors (which are far less powerful) comes close, and even then it's a tossup. Assuming roughly linear scaling with the simulations done thusfar, with enough advance warning, even a Chicxulub-scale impactor could be deflected / destroyed with a Tsar Bomba-sized device with a uranium tamper. Even though it was not designed to be light for space operations, its 27-tonne weight could be launched to LEO by a single Delta-IV Heavy and hauled off to intercept by a second launch vehicle.

Comment: Re:Not surprised (Score 5, Insightful) 311 311

Uber drivers are subsidized by everybody else. Taxi drivers have to pay high insurance rates because the act of driving a long distance every day for a ton of strangers is a job that inherently leads to a much higher statistical rate of payouts. If they're driving as a taxi on regular car insurance, it's you that's paying the bill for their swindle of the insurance system.

Comment: Re:What plan? (Score 1) 88 88

How do you come to that assumption?

By linking to a peer-reviewed paper on the subject?

A nuclear warhead has lots of trouble to even "hit" an asteroid.

Essentially every space mission we have launched for the past several decades has had to navigate with a far more precision than that needed to get close to an asteroid and activate a single trigger event when close by.

Comment: It would give them control of monetary policy (Score 1, Insightful) 357 357

Part of the issue in the Eurozone is that countries have control of fiscal policy, as in how money is spent and taxes collected, but not monetary policy, as in how much money is supplied and to where.

While monetary policy doesn't let you magic your way out of any situation (see Zimbawbe for an example) it can be useful. Have a currency that is weak or strong isn't inherently good and bad, but rather useful in different ways. So one country might wish to have a weaker currency, another a stronger one. Also it can allow for things such as higher inflation, which can be a problem, but can also be useful in some situations.

It wouldn't solve Greece's problem, to be sure, but there are ways it could potentially help.

Comment: Re:What plan? (Score 4, Interesting) 88 88

We send spacecraft on comparable missions all the time. And it doesn't really take a spectacularly large payload to destroy (yes, destroy) an asteroid a few hundred meters in diameter. 1/2-kilometer-wide Itokawa could be blown into tiny bits which would not recoalesce, via a 0,5-1,0 megatonne nuclear warhead, a typical size in modern nuclear arsenals (in addition, the little pieces would be pushed out of their current orbit).

I know it's a common misconception that "nuking" an asteroid would simply create a few large fragments that would hit Earth with even more devastation, but that's not backed by simulation data. And anyway, even if it didn't blow the asteroid to tiny bits (which simulations say it would) and even if it didn't push the remaining pieces off trajectory (which they say it does), anything that spreads an Earth impact out over a larger period of time is a good thing - it means the higher percentage of the energy that's absorbed high in the atmosphere rather than reaching the surface (less ejecta, lower ocean waves, a broader (weaker) distribution of the heat pulse, etc), the weaker the shockwaves, the weaker the total heat at any given point in time, and the more time for Earth to radiate away any imparted energy or precipitate out any ejecta cloud. If the choice is between 15 Chelyabink-sized impactor (most of which will strike places where they won't even be witnessed) or one Meteor Crater-sized impactor (same total mass), pick the Chelyabinsk ones. 50 10-megatonne meteor crater impactors or one 500-megatonne Upheaval Dome impactor? Pick the former. The asteroid impacts calculator shows the former generating a negligible fireball and 270mph wind burst at 2km distance, while the latter creates the same winds 25km away (156 times the area) and a fireball that even 25km away is 50 times brighter than the sun, hot enough to instantly set most materials on fire.

But that's all irrelevant because, quite simply, simulations show that nuclear weapons do work against asteroids.

What we need is enough detection lead time to be able to launch a nuclear strike a few months before the impact date (to give time for the debris to disperse). There is no need to "land" or "drill" for the warhead. There is no pressure wave; instead, an immense burst of X-rays is absorbed through the outer skin of the asteroid on the side of the explosion, causing it to vaporize (unevenly) from within, especially near the ground zero point, and creating powerful shockwaves throughout its body. In addition to ripping it apart, the vaporized material and higher energy ejecta flies off, predominantly on the side where the explosion was detonated, acting a broad planar thruster.

Comment: Also the Euro is stable and widely accepted (Score 3, Insightful) 357 357

Trying to push bitcoin only shows that the author has a poor understanding and an agenda. While you could, potentially, argue bitcoin in cases where a country's currency has collapsed, or is unable to be used to buy things from other countries. Bitcoin is highly volatile, a very poor store of wealth, but it is something you can spend and transfer, in some places at least, and at present it has value.

Well, that isn't an issue with the Euro. It is an extremely important and widely used currency, second only to the US Dollar. All Eurozone countries use it (by definition) which is quite a few major economies. As such it is also widely sought after in international currency exchanges. Euros are very easy to spend on the international scale. Many places will take them directly, and any bank will convert them.

Also the Euro is pretty stable. When you look at it compared to other major currencies like the Dollar, Pound, and the Yen it compares very well. All fluctuate, of course, but not very quickly. So it is a good store of value, you don't have to worry about losing your money. Works long term too, as many nations with good credit will sell debt instruments in Euros.

So there is nothing bitcoin solves here, because bitcoin is a currency and currency isn't the problem in Greece. This isn't Zimbawbe where the currency was worth nothing.

The only way it could "help" is to move money out in the event of capital controls on Greek banks. But of course:

1) You have to get the money out of the bank first, which a capital control can slow down.
2) The only way it facilitates that would be being less traceable. As I said, Euros are taken everywhere, you can convert them to Dollars or anything else.
3) Most importantly that wouldn't help the situation at all, it'd make it work. Might help an individual save money, but it would only worsen the situation.

Comment: It's mostly click-baitng, with a bit of stupid (Score 1) 285 285

A lot of it is just the run of the mill stupid site trying to drive up traffic with controversial headlines. Worked too, Slashdot linked to them. However part of it is just the guy being a derp and thinking that because the UI wasn't completely polished off it wasn't ready to go. Had he looked in to it, he'd realize that kind of polish is nearly always the things that comes last, right before release, for a variety of reasons.

Comment: Ummmmmm (Score 1) 81 81

If your funding is so bad that you can't afford anything newer than a P3 and a 17" CRT, I have to wonder just how good the research is that you do. Or maybe that you just don't understand how technology has changed.

I encountered the latter in my undergrad days. I was a psych major for a time, and as is tradition they force students to participate in experiments to get free subjects. So one of them was on Internet addiction. This was in the early 2000s, while broadband was not common it was not rare either and the university was of course on a dedicated link. All the questions were around "How long are you connected to the Internet?" and "How often do you log in?" and such things.

I tried to explain to the researcher such questions weren't meaningful to me, my computer was on all the time and I could just use it like any other program. They didn't understand, and figured I didn't understand and kept repeating the question. I tried to explain and demonstrate with their office computer. That failed though, because the thing was so slow it took the better part of a minute to launch IE, which they thought was dialing in to the Internet. For them it wasn't a seamless experience, they only used the Internet when they needed/wanted to since it was so slow. I could not communicate to them that for an ever increasing number of us, it wasn't like that, it was just a part of using a computer.

I've encountered things like this a number of additional times with psychology/sociology/behavioral researchers. Their grasp of computer technology is so poor that their studies are extremely flawed because they don't understand the tools they are using.

That aside, maybe this works, who knows without a link to the paper, but it seems like a more effective use of computers and dieting are the widespread calorie tracker apps. When people actually track what they take in, they often can do a much better job at preventing it from getting excessive.

Comment: Re:200 cycles? (Score 3, Insightful) 123 123

On the other hand, if they're doubling capacity, then you only need half the number of cycles (it actually even works *better* than that, as li-ion cells prefer shallow charges and discharges rather than deep ones - but yes, fractional charge cycles do add up as fractional charge cycles, not whole cycles). If you have a 200km-range EV and you drive 20 kilometers a day, you're using 10% of a cycle per day. If you have a 400km-range EV and you drive 20 kilometers a day, you're using 5% of a cycle per day.

Comment: Re:well then (Score 5, Insightful) 123 123

Top commercial li-ion capacities are about 30% more than they were 5 years ago. And today's batteries include some of the "advances" you were reading about 5 years ago.

I'm sorry if technology doesn't move forward at the pace you want. But it does move forward when you're not looking. Remember the size of cell phone batteries back in the day?

God helps them that themselves. -- Benjamin Franklin, "Poor Richard's Almanac"

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