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Comment Re:Incredibly farfetched (Score 1) 256

Well the nice thing is that there would be plenty of open space. I'm not sure why one-inch steel - steel doesn't seem to be an ideal material for this. I don't know what the effects of all that sulfide would have on carbon, but if it can be made resistant I would think seriously about starting small with a probe that can produce a carbon-based skin and build a bigger balloon for itself.

Comment Re:Incredibly farfetched (Score 3, Insightful) 256

Just to be clear - size is not largely irrelevant. The whole key to buoyancy is that the volume of a sphere goes up as the cube of the diameter while the surface area goes up as the square - for a non-sphere it's based on the three linear dimensions of course. So a very small craft can barely carry the skin, while a large one can carry much more in addition to the skin. There are other factors, but that's the primary one.

For example, a one-foot box made with one inch steel would not float well.

Comment Re:Huge waste of Resourses (Score 1) 256

I recall not that many years ago when the prospect of a teraflop processor was science fiction. That was about 1992. A year or two before that I worked on some photometrically-correct ray tracing code, porting it to the Cray X/MP. That code took a month to make one 1024x1024 frame on the top-end Apollo workstation, and a few minutes to run on the Cray. It could probably run at close to 30Hz on my phone today, and today's supercomputers are in the 30+ petaflop range, i.e. 3x10^16.

So we're getting close - theoretically, if all of the top 100 supercomputers got together, the group performance would be in the 10^19 range. :) Actually that's not a bad idea - the powers that be could work a deal for all of them to work together for one week per year on the same problem, and the research time could be allocated the way that telescope time is allocated according to accepted/agreed value of a particular project.

Comment Re: Atomospheric toxins. (Score 4, Interesting) 256

I had an idea a while back, that actually relates to TFA. Genetically engineered bacteria or simple organisms that could float and live in the Venusian atmosphere and gradually begin to 'fix' the sulfides and whatever - maybe pooping out metallic sulfur. For the first long while, they would be working at the top of the atmosphere. Their poop would drift down and re-vaporize (absorbing energy and lowering the temperature). When they died, they would drift down into deeper layers and get to the point where their bodies would be heated back up to the point where the materials would be turned back into gas. But as they became more populous, gradually they would reduce the amount of solar energy (especially if their bodies were reflective), and the temperature. Eventually the might be able to reduce the temperature to the point where their poop, or that of their successors, would fall to the surface, permanently eliminating the sulfides from the air.

Comment Re:It is a start (Score 2) 233

Better idea - use sophisticated computer programmed learning + continuous testing. Since students are learning and continually being retested on the material, and the questions are rarely the same for two different students (or even the same student 10 minutes later), nearly all cheating other than just standing there and answering for the student becomes impossible or at least impractical - IOW actually continuously monitor the students progress and help them actually _learn_ instead of faking it.

Of course, the education establishment really doesn't want to know a student's real capability, as this would elicit questions of actual performance, and ability - completely politically incorrect.

Comment Re:How to REALLY lie with statistics (Score 4, Interesting) 233

Cheating has been a serious problem among asian students at every grade level in Southern California, for at least two decades. Not only cheating but a variety of other ploys, such as harassing teachers into giving out extra credit assignments to those who pester them, which can be used to artificially increase their grades. (Extra credit improves grades more than poor test scores bring them down.)

Comment Re:'Doctor'? So why spout mistruth? (Score 1) 573

According to Wikipedia, atmospheric levels of CO2 have ranged as high as 7000 ppm (during the Cambrian period), at which time the rate of plant growth was as high or higher than any other time in the history of life. Present levels are scarily close to the lowest ever found, 180 ppm during the last glaciation.'' So I think you have your facts wrong. There is also satellite data and associated research showing that today, the deserts are greening up more than any time in recent history, due entirely to increased CO2.

It seems to me that being only a factor of two greater than the 'iceball Earth' level, out of a range of almost a factor of 20, puts us at present in the bot tom of the range. The geometric mean of 7000 and 200 is about 1180, which seems to be a not-unreasonable number compared to the geological record. This may, of course, mean that Florida is a rather small island and Bangladesh will need to hire the Dutch to build dikes.

Comment Re:Not only about temperature (Score 1) 573

And yet in previous epochs, atmospheric CO2 has ranged as high as 7000 ppm - more than 16 times the 'worst case' of 400 ppm presently under discussion. In fact, except during ice ages, it's been higher than the present value almost all the time. But the oceans were not (AFAIK) more acidic - or at least they had lots of life in them, including a majority of shelled creatures. If so, then perhaps the acidity (if it is actually occurring) may be a transition phenomenon.

Comment Re:Climate Engineering (Score 1) 573

I guess you've never heard about the intense growing season in Alaska, resulting in giant vegetables and other crops - 65 lb. cabbages feet in diameter. 24 hour sunlight has amazing effects on some plants. (Of course in some cases this natural phenomenon has been encouraged by selective breeding, etc. but that's beside the point.)

Also, increased CO2 has been shown to be a powerful plant growth stimulant.

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