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Comment Re:It is still just a theory (Score 1) 58

Mod parent up.

Too many people fall into the trap of mistaking scientific authority for scientific method. A scientist may be an excellent authority in his specialty, but he is still just an authority and is prone to all the kinds of errors of that any man can make. The scientific method with its hypotheses and experiments is the gold standard, and even its results should be rigorously questioned.

A scientist who is not a profound skeptic about just about everything is not really a scientist, but merely an imposter.

Comment Going a little beyond intuitive (Score 1) 58

TFA describes the situation on a dry asteroid.

An asteroid or comet that contains water as well as stone is likely to behave differently. If its ice is melted by impact or increased exposure to sunlight, then frost heaves might cause a faster migration of big stones to the surface than would happen by granular convection. But if the ice is acting as a concrete binding agent, then there will be no frost heaves and no granular convection. Probably on a lot of asteroids both processes will be active.

I'm thinking that determining whether frost heaves or granular convection has been at work is going to be important in figuring out how to deflect any asteroid or comet. I'n guessing this will need to be done on a case by case basis.

Comment Granular convection and frost heaves (Score 1) 58

There is possibly some confusion in parent post between granular convection and frost heaves.

In New England and other climes that have a winter freeze and spring thaw, the winter freeze pushes rocks upward as the water in the soil expands into ice. In the spring thaw, the ice under the rocks melts from the periphery inward, and slurries of ice water mud fill the voids. As a result, the rocks stay in their higher place as the soil settles back to its spring level.

One of my chores when I was growing up was to help with digging the big and deep holes in the garden next to the emerging boulders that were too large to remove. We'd roll the boulder into the deeper hole and bury it, and be able to use the rototiller and tractor over it for a few years before it would rise again.

Comment Re:syntax (Score 3, Interesting) 132

Some languages are simply easier to make mistakes in, thanks to insane syntax.

This is true. But it is not a weakness of the language. And do not confuse "insane syntax" with what Perl is doing.

Perl holds the author responsible for using the correct syntax in the context of the author's intent. It does not hold the author's hand, as if they were some kindergartner just starting out. One of Perl's axioms is that the author must be allowed to do whatever he wants without regard to some imposed notion of what is reasonable, for who but the author can know what his intention is?

That means a lot of shitty scripts are written in Perl. But a lot of shitty verbiage is written in English. Neither language should be judged by the great volume of shitty work that has been done in it. Each language should be judged by the quality of the most elegant work that it can support. There has been some really elegant work done in Perl.

For critical work, Perl should not be used by programmers who do not yet know what they are doing. While it is a great language for studying things like Knuth's work on algorithms (TAOCP), it should not be used in mission critical applications until the student has mastered those studies.

And determining which programmers are sufficiently capable to be allowed to use Perl is a problem for the IT managers and software team leaders. It is not a problem with the language.

Don't try to use Perl in anything that is mission critical until you no longer need the training wheels.

Comment Re:Photosynthesis has its disadvantages. (Score 1) 133

I agree with all the points made in parent post, except the one about "comparatively low efficiency".

Conversion of biomass left after harvest of crops to biochar involves pyrolysis which is exothermic and can produce electricity through steam or turbine driven generators. By properly marrying together mature technologies that we have been using for over a century we could be turning agricultural waste directly into electricity WHILE AT THE SAME TIME removing 30% - 50% of the carbon in that biomass from the active carbon cycle. When the charcoal that is produced is crushed into pea sized granules and tilled back into the field, it improves the soil while remaining sequestered for a few thousand years.

We should be putting more effort into plucking this kind of low hanging fruit, and less into esoteric research on manufacturing solar / chemical panels that will have serious costs of production, operation, and maintenance and will do nothing to reduce atmospheric CO2.

Of course this is all fully mature technologies, with little room for monetizing new patents. So only everybody would benefit. That doesn't attract investors to the project.

Comment Re:Great... Instead of CO2 we get CO (Score 1) 133

There is a notable lack of reading comprehension showing in parent post.

To make the obvious more clear, the vegetation is converted to charcoal. Roughly 30 - 35% of the carbon in the vegetation is sequestered, as charcoal, for tens of thousands of years, so long as it is kept too moist to burn. And to repeat, charcoal granules are an excellent soil amendment promoting better soil ecology and retention of irrigation water.

Google on "biochar" for more about this approach.

Comment Re:Amazing technology (Score 2) 133

Trees (and agricultural "waste") can be converted to charcoal through pyrolysis. About 1/3rd of the carbon that was captured by the plants becomes biochar, which is a useful soil ammendment, and which sequesters the carbon for tens of thousands of years. So in effect as good as changing it back into coal (but with nicer side effects, like apples, zucchini, etc).

Comment Re:Great... Instead of CO2 we get CO (Score 1) 133

Photosynthesis offers the same advantages, without the technology overheads. In addition it offers some nice byproducts, like grains, tomatoes, zucchini, etc.

Using vegetation as feedstock for charcoal production will effectively sequester carbon for tens of thousands of years, if not longer. Additionally, carbon sequestered in this way is a good soil ammendment, that can make poor soils more productive.

Google on href="http://en.wikipedia.org/wiki/Biochar">"biochar" for more about this approach.

Comment Re:The point (Score 3, Interesting) 133

We've already got CO2 scrubbing technology that is remarkably effective: photosynthesis in plants. In terms of cost/benefit, this method is by far more efficient than the one talked about in TFA. Plus there are numerous advantageous byproducts, like grains, tomatoes, zucchini, etc.

What we could use is a more effective means of sequestering the carbon in vegetation materials. Charcoal is great for sequestration: chemically inert for thousands of years, and with microscopic structures that promote good soil ecologies, much like coral promotes sea life. Currently most methods of producing charcoal return about 2 parts of carbon to the atmosphere for every part that is potentially sequestered ("potentially" since it needs to be put in soil or water and not in the barbeque).

"Biochar" is the word to google on for more about this form of carbon sequestation.

Comment Re:Pointless pork for manned spaceflight (Score 1) 65

Yeah yeah yeah. And there were those guys in ancient Greece who were ranting about wasting good fabric that could be used for useful things like togas on sails on boats that could do just as well with a few oarsmen. They saw no practical value in being able to boat from island to island, since there was nothing on fabled Crete or the delta of the Nile that could not be fashioned from the stuff within a donkey's trot of Athens.

Comment Re:Dog and the Car (Score 2) 65

Setting up gas stations in the asteroid belt could work quite well, I would think.

I begin to see the point of NASA's interest in mining the asteroids. It might be possible that water could be extracted from an asteroid by a solar powered satellite, then shipped by cheap, slow, unmanned rockets to rendezvous points for manned missions. Water has some excellent qualities for use as reactive mass in rocket motors, especially those with nuclear rather than chemical heaters, and a ship that only needed to carry enough reaction mass to get from one rendezvous to the next could open up the solar system to manned exploration very quickly. This would make a manned mission to Mars much easier.

But first there is a need to determine whether we have technology that can do the extraction, and whether there is enough water in the asteroids to make it worthwhile. Could a solar powered laser aimed at a point on an asteroid create a plume of water vapor that could be captured somehow and condensed into liquid or ice? Interesting concept...

Comment Re:Easier (Score 1) 106

Except washing your hands with antibiotic soap is introducing low levels of that antibiotic downstream from your sink. Into places where bacteria thrive, and compete with each other. Bacteria that develop antibiotic resistance in that environment are healthier and better able to compete.

Unless you are boiling your gray water after washing up with antibiotic soap, you ARE contributing to the increase in low dose antibiotics in the greater ecosystem, and that is definitely a part of the problem.

Comment Re:Dangerous (Score 1) 345

That I agree with. I'm a bicyclist, I use a rear view mirror mounted on my hazard glasses, and I'm pretty good about maintaining situational awareness. You get that way after pedalling for 45+ years. But there was still one time when a silent Prius sneaked up on me in a parking lot. Really startled me, like finding a rattlesnake in a mailbox.

Cars and motorbikes should make a little noise. Not very much, but a little. (Good bicyclists know how to say "behind you", "on your left", etc).

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