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Comment: Re:no we can't (Score 1) 31 31

by Rei (#50017541) Attached to: Asteroid Day On June 30 Aims To Raise Awareness of Collision Risks

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: Look the part (Score 1) 61 61

by the_Bionic_lemming (#50016793) Attached to: The Programmer's Path To Management

Yeah - sorry dice - dressing pretty to become a boss just shows how stupid people who want to be bosses are.

And that's why competent people hate them.

Clothing does not reflect ability. I'm quite sure I can code far better naked than someone who thinks spend two or three grand on an Armani overhaul can.

Comment: Re:Not surprised (Score 3, Insightful) 226 226

by Rei (#50015665) Attached to: Uber France Leaders Arrested For Running Illegal Taxi Company

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: It's a great idea (Score 2) 81 81

It's a good marketing move - most people just download the free version and scan. Problems fixed so they won't buy it for the bells and whistles - now they'll get lots of people to try the bells and whistles and might retain future revenue.

It's better than them canceling the free version and make it pay only for revenue.

Comment: Re:Fucking Lawyers (Score 2) 151 151

by roman_mir (#50013985) Attached to: SCOTUS Denies Google's Request To Appeal Oracle API Case

My position on copyrights and patents was always the same: abolish all patents and copyrights and prevent government from providing monopolies with these laws.

Basically this is nearly the ultimate absurd result that we are seeing here and it probably can even get worse. You want to build a road somewhere? Well, you are violating a copyright on other people building horizontal surfaces to allow circular wheels (and legs I suppose) to run on them. You want to build a house? Are you going to have a roof? Foundation? Walls? Windows? Doors? Fucking copyright violator. Absurd, isn't it? Or is it really absurd to expect that ruling like that can actually be passed given the fact that it is a government entity that can pass that ruling and given that governments are already given authority to rule on these issues?

No, the real solution is not even about money exchanging hands (though I wouldn't be surprised in case of Oracle), it is about the power that governments have over our heads, and this power is as insane as it is absurd.

No company or person should be given government protected monopoly on anything, including any invention, copyright, whatever. That's not how evolution works, that's not how cultures worked and still keep working. That type of power is destructive, not constructive in any way. Let the people and companies decide how to provide their services and products in a world that does not automatically protect them from any type of competition. At the very least this cannot be a power granted to government, deal with these issues on contract basis and using trade secrets if you must.

Anyway, I can only leave 1 or 2 comments here now given that 24 hours passed since my account's 'karma' was obliterated again by moderators who want to make sure I cannot reply to comments made to me, so don't expect many comments here either.

Comment: Re:Fucking Lawyers (Score 1) 151 151

by roman_mir (#50013539) Attached to: SCOTUS Denies Google's Request To Appeal Oracle API Case

You mean in the same way that a manufacturer of a spoon "illegally copied" information about a human mouth?

In the same way that a road construction crew "illegally copied" information about wheels being round?

In the same way that a manufacturer of a catheter "illegally copied" information about urethra?

This is API, API is information about CONNECTING pieces together, it is a contract information, definition of connectivity, not implementation details.

This is not a problem that is just related to Java somehow either, this concerns everything, every language, nearly every field and industry.

Comment: Re:What plan? (Score 1) 85 85

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: Re:"Are" or "could be"? (Score 0) 103 103

by roman_mir (#50012429) Attached to: 79% of Airbnb Listings In Barcelona Are Illegal

1. Who says 'my business' is causing a disturbance? Do you generally know which hotel somebody stays in if they are running around drunk on the street?

2. I don't believe for a moment that there is an actual problem of that type, most people sleep at night and I am almost completely sure this entire fucking article is a gigantic exaggeration like pretty much everything else that pops into the media.

3. Hotels being in so called 'commercial districts' does not change the hotel customers being drunk 1 block away from the hotel, beside which hotels are mostly located near private housing anyway, not in factory or warehouse zones.

4. By my standards there is no question at all, I am completely against all government involvement into any business and money, so no, by my standards this is a cut and dry case of government oppression. You are the one full of shit, hotels are located near other houses and buildings all the time and their clients can get drunk and noisy anywhere at all, be it a city or a beach or transit or whatever.

Comment: Re:What plan? (Score 3, Interesting) 85 85

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: Re:200 cycles? (Score 3, Insightful) 122 122

by Rei (#50008581) Attached to: Samsung Nanotech Breakthrough Nearly Doubles Li-Ion Battery Capacity

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) 122 122

by Rei (#50008563) Attached to: Samsung Nanotech Breakthrough Nearly Doubles Li-Ion Battery Capacity

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?

Comment: Re:"Are" or "could be"? (Score 0) 103 103

by roman_mir (#50003515) Attached to: 79% of Airbnb Listings In Barcelona Are Illegal

A bunch of nonsense. Somebody got drunk and noisy, so what? People living in those houses never drink? Never get noisy? People don't leave hotels and don't get noisy and drunk? Are hotels covering tourist behaviour outside of hotel premises? You are full of shit, just like this entire case.

The rate at which a disease spreads through a corn field is a precise measurement of the speed of blight.

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