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Comment: OMG - matti makkonen .fi sms pioneer dead (Score 1) 10 10

by Rei (#50018263) Attached to: SMS Co-Inventor Matti Makkonen Dead At 63

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 1) 35 35

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: Fun places to watch fireworks (Score 1) 117 117

by billstewart (#50017051) Attached to: My relationship to 4th of July noise:

Your own front yard, or back yard, or the street, of course, preferably with illegal fireworks. Or the beach. As a friend put it, for any holiday celebrating the overthrow of the government, the question of whether your fireworks are legal simply shouldn't come up.

Most of California's way too dry to allow the things, but there's one town near San Francisco (Pacifica) that's always wet enough they're not worried about moderate levels of fireworks, so the local fire department sells them, and you're allowed to set them off down on the beach, and in practice locals also set them off on the street. Several friends have lived there, and we've had a few good July 4th parties and a Canada Day party (too foggy, but lots of fun; it's July 1, and it was the weekend that year.)

My town used to have a freeway exit that was closed for construction, so there was a big pile of dirt twice as high as the bridge is now, and the neighbors would all take our lawn chairs up to the top to watch fireworks, including the official town shindig (minus the traffic), and the amusement park down the road, a couple of towns north and south, and the illegal backyard fireworks. Another place I lived was on a bay, and for some big firework years we could go down to the dock and see fireworks from a bunch of different towns across the water.

Comment: Re:Not surprised (Score 4, Insightful) 233 233

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: Re:Cool (Score 1) 188 188

by BasilBrush (#50013339) Attached to: iPhone 6S New Feature: Force Touch

What you don't appreciate is that there is always a cost to adding UI. If the phone has windowing then there has to be some means of activating it. And that's extra UI. And if that extra UI has to work with the iPhone, then that has implications for how it's implemented on the iPad.

The windowing system on the iPad is really sweet. It uses the dimensions of the screen really well. Why potentially fuck it up for no gain by implementing windowing on iPhone?

What people miss about the essence of good design is it's as much about what you leave out as what you add.

Comment: Re:What plan? (Score 1) 86 86

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:What plan? (Score 4, Interesting) 86 86

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:Science can say a lot about what's good and bad (Score 1) 305 305

by iluvcapra (#50009073) Attached to: Lawrence Krauss On the Pope's Encyclical: Not Even Close?

We need to preserve the diversity of life to survive.

Right, but what if we engineered ourselves out of this necessity? It's completely conceivable that we could. Do we maintain diversity of living things just because human beings require a diversity of food? Or do species have a right to exist independent of the human need for survival?

Chemist who falls in acid will be tripping for weeks.

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