Slashdot is powered by your submissions, so send in your scoop


Forgot your password?
For the out-of-band Slashdot experience (mostly headlines), follow us on Twitter, or Facebook. ×

Comment: Re:Build colonies on Earth (Score 1) 165 165

There are pretty good reasons for believing that a key to the improved environment on Earth will be the migration of many processes off the planet. I'm not a particular fan of Space Solar Power, but it's definitely in the running. According to experts in the field, SSP could eliminate all of the power plants on Earth (both fire-based and nuclear) and provide easy cheap power everywhere for less. (IMHO it would be cheaper in the short run to just build big solar facilities in the Sahara, 30 feet off the ground. This would generate plenty of power and provide a new resource underneath - shade where things could be grown.)

Comment: Re:Build colonies on Earth (Score 3) 165 165

As someone who is involved (peripherally) in the "New Space" movement, IMHO the first purpose of space development will be the availability of new resources and technologies. An economist a couple of years ago predicted that space development would have the potential to increase the standard of living of everyone on Earth by a factor of 10. That seems optimistic to me, but a reasonable goal. One popular example (see Planetary Resources, Inc.) regards the availability of Platinum, which is a very useful industrial metal, but is unfortunately $1300 per ounce. Platinum mining is expensive, dangerous, and disastrous both ecologically and socially. This greatly restricts is usefulness although it is used in those expensive catalytic converters in your car - that's why they're expensive. The best astronomical physicists believe that some of the Near Earth Asteroids contain single-digit percentages of Platinum. If this is true, then a 100 meter asteroid would contain a dozen times as much Platinum as has ever been mined. Retrieving this material to Earth could drop the price to between $10 and $100 per ounce, and this would still be economically viable for the company to process in space and ship it down to Earth.

There are many other examples. Technologically, the range of industrial processes that are presently either expensive or impossible on Earth due to gravity and air, that could be done in the high vacuum and microgravity of space is broad but it is likely that an order of magnitude more new processes that have not even been envisioned yet will be discovered or invented. Orbital production of high quality integrated circuits might well be one - one of the most expensive aspects of IC manufacturing is the requirement to build a huge facility and maintain a high level clean room environment. In space that could be done with not much more than a bit of Mylar.

Comment: Re:Incredibly farfetched (Score 1) 165 165

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 2) 165 165

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) 165 165

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 1) 165 165

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) 233 233

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) 233 233

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) 573 573

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) 573 573

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:Golden Rice (Score 1) 573 573

I've always thought that, if you believe 'everyone' should live a certain way, then you should live that way. If you are correct, eventually others will follow. By extension, if you believe that humans are evil and should all die off, then be my guest, start the trend.

"Everyone is entitled to an *informed* opinion." -- Harlan Ellison