Wow, you keep bringing up deaths as though I didn't write a whole post about that.
And as for Cesium-137, it's the primary reason that the Chernobyl exclusion zone still exists. Cesium is readily ingestible; it's a sodium/potassium analogue.Mayes 1994 found that the bioavailability of Cesium-137 is high.
1) You forget about capacity factor. 2) You forget about generation losses 3) Solar farms are generally sparsely spaced in order to prevent self-shadowing and to make maintenance easier.
Only if you look at particular pollutants (aka, not CO2) and ignore that the impact of those pollutants depends strongly on where they're emitted (if there's nobody to breathe a particular pollutant before it breaks down, does it really matter that much?).
At Solar One, there were 13 birds that died that way in a 40-week study period. Most bird deaths at Solar One were collisions with the heliostats, nor burning. And, to be quite blunt, *some* birds are going to collide with anything you build. Birds die in collisions with rocks and trees, too (and *tons* die in collisions with our other structures -- power lines, windows, communications towers, etc).
Solar One was believed to be unusually attractive to birds because it was cited in the desert near an irrigated agricultural area, which provided an oasis where insects were plentiful for them to eat. It's expected that there will be fewer bird deaths per MW in more remote siting.
Oh, God -- got to love an article that starts out talking about wind power by bringing up Altamont Pass. Altamont Pass was a *1970s* wind farm. It was built with very little study (unlike today's requirements), and if you wanted to design a rapor cuisinart, that would be the way you would do it. They built it in the middle of a raptor flyway with low turbines with fast-spinning blades and a tower structure that encouraged birds to try to land on them. Comparing Altamont Pass to modern wind farms is just absurd. Despite them generating a tiny fraction of our wind power, Altamont and a couple other old farms cause over 80% of wind-related raptor deaths.
Then they bring up the American Bird Conservatory. The American Bird Conservatory, like the Audubon Society, supports wind power when it's designed with birds in mind. The very paper that ABC cites for their numbers ("A Summary and Comparison of Bird Mortality from Anthropogenic Causes with an Emphasis on Collisions") states "The high level of mortality associated with the Altamont wind plant has not been documented at newer wind plants constructed at other sites." The paper's conclusions are amazingly *supportive* of wind turbines (noting, for example, that wind turbines average 1.5 bird fatalities per year, while communication towers average 8.1). They come up with a figure of 3.04 bird fatalities per MW per year for wind power. They estimate that wind power killed 20-37k birds per year as of the 6.4GW installed capacity as of 2003 (compared to the 500M-1B birds killed by anthropogenic causes alone). ABC's "1 million birds" number is nowhere in the first paper that they cite. One can only conclude that they did some crazy extrapolation which was heavily biased by Altamont and other early wind farms which did not consider birds in their designs and used older, fast-turning blades. They also mention another paper by FWS, but fail to give a proper reference to it; I searched the FWS's site and can find nothing to back it up.
That whole WSJ article is based on a big lie -- that only wind power gets an exemption from bird kills. In the US, cars kill 60-80m birds per year, with more from planes and trains. 100m to 1b birds in the US per year die from window strikes. The number for US high tension lines is roughly 130m. For communication towers, the estimate is 4-5m (and rapidly growing). 67m are estimated to die from pesticides. And on and on. How many of these death sources do you think are getting sued?
I don't get your point. Because tall structures exist, nuclear power is good?
If you don't leave, it absolutely does "keep ticking". So you have to leave. Homes, businesses, factories, farms, everything. "Out soon enough" and "only a few days"? You realize that the half life of cesium-137 is over 30 years, right?
Please show me your 20-30km (plus spots up to 60km) wind turbine exclusion zone.
You have an image -- a running image. One that is effectively updated thousands of times per second. You can downsample it to whatever framerate you want.
MJPEG is precisely the opposite. MJPEG is a bunch of complete still frames compressed individually.
That's what the mbps figure is for -- it's how much data the camcorder is keeping post-compression. A camera which can store 24mbps x264 is storing roughly twice as much (actually, more) information in comparison to a camera that stores 12mbps x264, all issues of compression algorithm quality being equal. 24mbps is basically blu-ray quality (Blu-ray goes up to 40mbps, but I don't know of any movies that actually use that; even Avatar was 33mbps). Now, yes, professional cinema cameras generally record in raw format instead of pre-compressing. But that's not really the issue; ignoring that 24mbps x264 1920x1080p is quite close to raw, the issue is that commercial camcoders can capture that at 60fps *and* compress it in realtime.
Why would it require much more light sensitive cameras? Frame addition for downsampling to common framerates should be equivalent to less frequent CCD polling unless your polling is introducing significant CCD noise (or you're not storing raw video).
It just amazes me how backwards the motion picture industry is in all of this. I mean, I have a $750 consumer-grade camcorder that does 1920x1080p at 60fps, 24mbps write speed. There's not a hardware issue out there if *consumer-grade camcorders* can manage that.
You know, I wonder when we'll ultimately just drop the concept of "frames" and switch to temporal-tagged packets of image changes, without requiring a full image to have been acquired simultaneously. Aka, your CCD doesn't accumulate photon counts, but photon rates. The readout from the CCD returns the delta between the current rate of activation and the previous activation rate. For a CCD polled thousands of times per second, for most pixels, that would be near zero, and that pixel is declared "unchanged" and ignored. The pixels which have a statistically significant changes are returned to the camera as ID/rate pairs, and are all bundled together with a time tag, processed, and compressed. Then it's a trivial matter to assemble them into whatever frame rate you want, it makes it much easier to do high quality slow motion, etc. Our insistence on accumulating all data into (proportionally slow) "frames" during the recording process is throwing away data.
Of course, this would require some significant hardware and video format changes, plus different approaches to compression, as the data you're reading is loosely packed instead of densely packed. Good compression approaches would take into account the strong regional correlations between pixels reporting changes in light intensity.
Real life is "unnaturally smooth". The frame rate on reality is approximately 1.85486e43 fps (give or take due to uncertainties in the value of Planck time).
And really -- upconversion is your standard? Really?
For the 8,672nd time, nuclear disasters are disasters in slow motion. Big wave comes up, slams into shore, retreats. A couple followup waves and it's done. Radiation exposure, however, keeps tick, tick, ticking. You can run from a disaster in slow motion. So few people tend to die in nuclear disasters. But what you can't do is pretend that they didn't happen, to ignore them. If you don't leave, *then* you get sick and die. You have to abandon the cities, you have to stop the farming nearby, the ranching, the fishing, etc. You have to put tremendous efforts into containment, or all of that gets even worse. Hence, nuclear disasters tend to be not about deaths, but about hardship, fear, and huge economic losses.
Oh, and FYI, wind turbines are extremely earthquake-resistant. The towers are way overbuilt in order to withstand the wind loading, and their shapes tend to be excellent for damping.
That's the problem -- no, they don't. Look at how much the Edwards elevator was estimated to cost. That involved assuming a bulk ribbon of 100+GPa. The strongest *individual* SWNTs ever measured thusfar were a mere 62GPa. That's a huge difference in terms of taper factor -- and that's for the *strongest* *individual tubes* ever measured. Bulk fabrics are going to be far weaker than their strongest tubes.
Just from this alone, a space elevator is a nonstarter on Earth. Do we even need to get into how inefficient they are?
Sky Hooks are hugely problematic for many reasons that aren't even worth getting into here. Just go with actively suspended structures. There's no good reason not to. They're stable, highly efficient at transferring energy to spacecraft, readily buildable with current materials, and the maintenance energy costs are proportionally insignificant.
No, what is hard for *you* to understand that no matter where you cut spending, it's going to cut jobs? Military spending is not special in that regard. So if your goal is to cut spending, tough -- you're going to kill jobs. Deficit spending is stimulative (in the short term).
It doesn't matter whether you use a low-energy launch trajectory or a high energy; the cost isn't the energy. It's the spacecraft designed to harness said energy. If you want a higher energy trajectory, you not only need more propellant, but a more expensive rocket; it doesn't change the equation. The propellant is still only in the low single digits as far as costs go. LOX, the most common oxidizer, is practically free compared to the cost of the rocket;)
Just because you don't follow materials technology doesn't mean it hasn't advanced.
Just look at the backpacking gear market. When I was growing up, the lightest waterproof fabrics you could get that wouldn't fall apart in an instant was polyurethane, several ounces per square meter. For years now, the best has been silnylon, at just over 1 ounce per square meter. Now it's stuff like cuben, at about a third of an ounce per square meter. That's an order of magnitude improvement since I grew up. You see that in every type of backpacking material. When I was growing up, GoreTex was the new thing. Wow, a plastic that will (mostly) keep water out and let your skin breathe (a little)! It's laughable compared to modern fabrics like Epic. And abrasion resistant-fabrics, and high tensile strength per unit mass cords, and on and on... materials tech just keeps taking off. Carbon Fiber wasn't invented until the 1960s. The first carbon fibers were only 55% carbon and rather weak. By the late 1970s, they were up to 85%. NASA largely pioneered the development of RCC (Reinforced Carbon-Carbon) during the Shuttle Program, eventually leading to commercial applications like brake disks. But RCC itself is already being replaced by C/SIC. And the thing is, we've barely even started to take advantage of the amazing material properties that nanoscale assembly can provide.
And what on Earth does Mars's lack of a magnetosphere have to do with anything?
Everybody knows that the solution to end the $1.6 trillion deficit is to cut the $700 billion military spending, while leaving the $800 billion health care and $700 billion social security spending intact.
The current extremes of our deficit are due to the fact that we're in the greatest recession since the Great Depression. In case you didn't notice. Our average deficits are a fraction as much. And our deficits are as much if not more a problem of continued tax cuts then they are of spending.
That is, if you forget that nearly half of those $700 billion military spending is manpower cost, which would become unemployment benefits
So military spending causes stimulus but other kinds of spending don't? Really? So old people don't buy stuff when they get their social security checks? Doctors and nurses live in caves and burn their cash for warmth?
Not at all. Space elevators are *extremely* sensitive to mass issues. In all practicality, an Earth elevator couldn't even support its own mass without an absurd taper factor (never minding the known other issues, such as induced harmonic oscillations).
Space elevators work great in sci-fi. Not so much in practice. If we ever want suspended structures on Earth, they're likely going to require active suspension, such as a Launch Loop.
Thankfully, the solar radiation shielding part isn't too difficult, as the particles are lower energy. Keeping fluids at the skin and having a proper storm shelter should probably be good enough, and solar radiation shielding via electromagnetic deflection is also feasible. GCR is much tougher; even though the flux is lower, the energies are much higher and much more difficult to stop, whether using active or passive shielding. I think it's likely that with current tech, we'd have to accept our astronauts having significantly increased chances of cancer, infertility, etc.
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Wow, you keep bringing up deaths as though I didn't write a whole post about that.
And as for Cesium-137, it's the primary reason that the Chernobyl exclusion zone still exists. Cesium is readily ingestible; it's a sodium/potassium analogue.Mayes 1994 found that the bioavailability of Cesium-137 is high.
1) You forget about capacity factor.
2) You forget about generation losses
3) Solar farms are generally sparsely spaced in order to prevent self-shadowing and to make maintenance easier.
Only if you look at particular pollutants (aka, not CO2) and ignore that the impact of those pollutants depends strongly on where they're emitted (if there's nobody to breathe a particular pollutant before it breaks down, does it really matter that much?).
At Solar One, there were 13 birds that died that way in a 40-week study period. Most bird deaths at Solar One were collisions with the heliostats, nor burning. And, to be quite blunt, *some* birds are going to collide with anything you build. Birds die in collisions with rocks and trees, too (and *tons* die in collisions with our other structures -- power lines, windows, communications towers, etc).
Solar One was believed to be unusually attractive to birds because it was cited in the desert near an irrigated agricultural area, which provided an oasis where insects were plentiful for them to eat. It's expected that there will be fewer bird deaths per MW in more remote siting.
Oh, God -- got to love an article that starts out talking about wind power by bringing up Altamont Pass. Altamont Pass was a *1970s* wind farm. It was built with very little study (unlike today's requirements), and if you wanted to design a rapor cuisinart, that would be the way you would do it. They built it in the middle of a raptor flyway with low turbines with fast-spinning blades and a tower structure that encouraged birds to try to land on them. Comparing Altamont Pass to modern wind farms is just absurd. Despite them generating a tiny fraction of our wind power, Altamont and a couple other old farms cause over 80% of wind-related raptor deaths.
Then they bring up the American Bird Conservatory. The American Bird Conservatory, like the Audubon Society, supports wind power when it's designed with birds in mind. The very paper that ABC cites for their numbers ("A Summary and Comparison of Bird Mortality from Anthropogenic Causes with an Emphasis on Collisions") states "The high level of mortality associated with the Altamont wind plant has not been documented at newer wind plants constructed at other sites." The paper's conclusions are amazingly *supportive* of wind turbines (noting, for example, that wind turbines average 1.5 bird fatalities per year, while communication towers average 8.1). They come up with a figure of 3.04 bird fatalities per MW per year for wind power. They estimate that wind power killed 20-37k birds per year as of the 6.4GW installed capacity as of 2003 (compared to the 500M-1B birds killed by anthropogenic causes alone). ABC's "1 million birds" number is nowhere in the first paper that they cite. One can only conclude that they did some crazy extrapolation which was heavily biased by Altamont and other early wind farms which did not consider birds in their designs and used older, fast-turning blades. They also mention another paper by FWS, but fail to give a proper reference to it; I searched the FWS's site and can find nothing to back it up.
That whole WSJ article is based on a big lie -- that only wind power gets an exemption from bird kills. In the US, cars kill 60-80m birds per year, with more from planes and trains. 100m to 1b birds in the US per year die from window strikes. The number for US high tension lines is roughly 130m. For communication towers, the estimate is 4-5m (and rapidly growing). 67m are estimated to die from pesticides. And on and on. How many of these death sources do you think are getting sued?
If you want to be technical, the term is "half-life" (hyphenated).
Short half-lives? Um, what part of 30 years is short to you?
I don't get your point. Because tall structures exist, nuclear power is good?
If you don't leave, it absolutely does "keep ticking". So you have to leave. Homes, businesses, factories, farms, everything. "Out soon enough" and "only a few days"? You realize that the half life of cesium-137 is over 30 years, right?
Please show me your 20-30km (plus spots up to 60km) wind turbine exclusion zone.
You have an image -- a running image. One that is effectively updated thousands of times per second. You can downsample it to whatever framerate you want.
MJPEG is precisely the opposite. MJPEG is a bunch of complete still frames compressed individually.
That's what the mbps figure is for -- it's how much data the camcorder is keeping post-compression. A camera which can store 24mbps x264 is storing roughly twice as much (actually, more) information in comparison to a camera that stores 12mbps x264, all issues of compression algorithm quality being equal. 24mbps is basically blu-ray quality (Blu-ray goes up to 40mbps, but I don't know of any movies that actually use that; even Avatar was 33mbps). Now, yes, professional cinema cameras generally record in raw format instead of pre-compressing. But that's not really the issue; ignoring that 24mbps x264 1920x1080p is quite close to raw, the issue is that commercial camcoders can capture that at 60fps *and* compress it in realtime.
Why would it require much more light sensitive cameras? Frame addition for downsampling to common framerates should be equivalent to less frequent CCD polling unless your polling is introducing significant CCD noise (or you're not storing raw video).
It just amazes me how backwards the motion picture industry is in all of this. I mean, I have a $750 consumer-grade camcorder that does 1920x1080p at 60fps, 24mbps write speed. There's not a hardware issue out there if *consumer-grade camcorders* can manage that.
You know, I wonder when we'll ultimately just drop the concept of "frames" and switch to temporal-tagged packets of image changes, without requiring a full image to have been acquired simultaneously. Aka, your CCD doesn't accumulate photon counts, but photon rates. The readout from the CCD returns the delta between the current rate of activation and the previous activation rate. For a CCD polled thousands of times per second, for most pixels, that would be near zero, and that pixel is declared "unchanged" and ignored. The pixels which have a statistically significant changes are returned to the camera as ID/rate pairs, and are all bundled together with a time tag, processed, and compressed. Then it's a trivial matter to assemble them into whatever frame rate you want, it makes it much easier to do high quality slow motion, etc. Our insistence on accumulating all data into (proportionally slow) "frames" during the recording process is throwing away data.
Of course, this would require some significant hardware and video format changes, plus different approaches to compression, as the data you're reading is loosely packed instead of densely packed. Good compression approaches would take into account the strong regional correlations between pixels reporting changes in light intensity.
Real life is "unnaturally smooth". The frame rate on reality is approximately 1.85486e43 fps (give or take due to uncertainties in the value of Planck time).
And really -- upconversion is your standard? Really?
For the 8,672nd time, nuclear disasters are disasters in slow motion. Big wave comes up, slams into shore, retreats. A couple followup waves and it's done. Radiation exposure, however, keeps tick, tick, ticking. You can run from a disaster in slow motion. So few people tend to die in nuclear disasters. But what you can't do is pretend that they didn't happen, to ignore them. If you don't leave, *then* you get sick and die. You have to abandon the cities, you have to stop the farming nearby, the ranching, the fishing, etc. You have to put tremendous efforts into containment, or all of that gets even worse. Hence, nuclear disasters tend to be not about deaths, but about hardship, fear, and huge economic losses.
Oh, and FYI, wind turbines are extremely earthquake-resistant. The towers are way overbuilt in order to withstand the wind loading, and their shapes tend to be excellent for damping.
The short answer: Yes.
That's the problem -- no, they don't. Look at how much the Edwards elevator was estimated to cost. That involved assuming a bulk ribbon of 100+GPa. The strongest *individual* SWNTs ever measured thusfar were a mere 62GPa. That's a huge difference in terms of taper factor -- and that's for the *strongest* *individual tubes* ever measured. Bulk fabrics are going to be far weaker than their strongest tubes.
Just from this alone, a space elevator is a nonstarter on Earth. Do we even need to get into how inefficient they are?
Sky Hooks are hugely problematic for many reasons that aren't even worth getting into here. Just go with actively suspended structures. There's no good reason not to. They're stable, highly efficient at transferring energy to spacecraft, readily buildable with current materials, and the maintenance energy costs are proportionally insignificant.
No, what is hard for *you* to understand that no matter where you cut spending, it's going to cut jobs? Military spending is not special in that regard. So if your goal is to cut spending, tough -- you're going to kill jobs. Deficit spending is stimulative (in the short term).
It doesn't matter whether you use a low-energy launch trajectory or a high energy; the cost isn't the energy. It's the spacecraft designed to harness said energy. If you want a higher energy trajectory, you not only need more propellant, but a more expensive rocket; it doesn't change the equation. The propellant is still only in the low single digits as far as costs go. LOX, the most common oxidizer, is practically free compared to the cost of the rocket ;)
Just because you don't follow materials technology doesn't mean it hasn't advanced.
Just look at the backpacking gear market. When I was growing up, the lightest waterproof fabrics you could get that wouldn't fall apart in an instant was polyurethane, several ounces per square meter. For years now, the best has been silnylon, at just over 1 ounce per square meter. Now it's stuff like cuben, at about a third of an ounce per square meter. That's an order of magnitude improvement since I grew up. You see that in every type of backpacking material. When I was growing up, GoreTex was the new thing. Wow, a plastic that will (mostly) keep water out and let your skin breathe (a little)! It's laughable compared to modern fabrics like Epic. And abrasion resistant-fabrics, and high tensile strength per unit mass cords, and on and on... materials tech just keeps taking off. Carbon Fiber wasn't invented until the 1960s. The first carbon fibers were only 55% carbon and rather weak. By the late 1970s, they were up to 85%. NASA largely pioneered the development of RCC (Reinforced Carbon-Carbon) during the Shuttle Program, eventually leading to commercial applications like brake disks. But RCC itself is already being replaced by C/SIC. And the thing is, we've barely even started to take advantage of the amazing material properties that nanoscale assembly can provide.
And what on Earth does Mars's lack of a magnetosphere have to do with anything?
The current extremes of our deficit are due to the fact that we're in the greatest recession since the Great Depression. In case you didn't notice. Our average deficits are a fraction as much. And our deficits are as much if not more a problem of continued tax cuts then they are of spending.
So military spending causes stimulus but other kinds of spending don't? Really? So old people don't buy stuff when they get their social security checks? Doctors and nurses live in caves and burn their cash for warmth?
Apparently neither the pot nor the kettle ever learned to detect sarcasm.
One of my favorite anecdotes from the Apollo era was the flashes of light they kept seeing. It was from radiation impacting their retinas.
Cataracts are very common among astronauts, especially the Apollo astronauts.
Not at all. Space elevators are *extremely* sensitive to mass issues. In all practicality, an Earth elevator couldn't even support its own mass without an absurd taper factor (never minding the known other issues, such as induced harmonic oscillations).
Space elevators work great in sci-fi. Not so much in practice. If we ever want suspended structures on Earth, they're likely going to require active suspension, such as a Launch Loop.
Thankfully, the solar radiation shielding part isn't too difficult, as the particles are lower energy. Keeping fluids at the skin and having a proper storm shelter should probably be good enough, and solar radiation shielding via electromagnetic deflection is also feasible. GCR is much tougher; even though the flux is lower, the energies are much higher and much more difficult to stop, whether using active or passive shielding. I think it's likely that with current tech, we'd have to accept our astronauts having significantly increased chances of cancer, infertility, etc.
It's called aerocapture, and it's been done on the Earth-side already. Aerobraking is also a (slower) option.