One good measure is the thermodynamic efficiency. This is the maximum theoretical fraction of a given amount of heat that can be converted to useful work, and it's just given by 1 - Tc/Th, where Th is the temperature of your source of heat and Tc is the temperature of your sink (where the heat goes). You can see that if you have no temperature difference at all (Tc == Th) you get an efficiency of zero, and if you have either an infinitely hot heat source (Th -> inf) or an infinitely cold heat sink (Tc -> 0) you get perfect efficiency and can transform heat to work perfectly. Reality is, of course, in between.
Incidentally, the reason you need both a heat source and a heat sink is that it is the flow of heat that you can tap to do work, like you can sink a waterwheel into a rushing stream, or like you can put a lamp or other electrical device into a flow of electrons.
It's not quite the quality of the heat per se that matters, then, but the quality of the heat flow, captured in the difference in temperature. It's like the drop in water height that you tap for a hydroelectric plant, or a voltage drop across a battery -- the larger the drop, the better.
One of the reasons solar power is a good source of useful energy is because the effective temperature of sunlight is equal to the temperature of the sun's surface -- about 5500K. That's very high. Any engine, such as a photosynthesizing plant, that takes energy from sunlight and uses ambient air (300K) as the heat sink can be very efficient.
Uh, if the men are from Mars and the women from Venus, how did they end up here on Earth? Possibly each was sent here by whoever else lives on Mars and Venus, respectively.
Apparently we humans are rejects from two worlds...
But...why is having roughly 1g of gravity worth the enormous trouble of coping with pressures comparable to those at the bottom of the ocean? And temperatures so high in a corrosive atmosphere that only special and expensive building materials could stand it?
What's wrong with having only a third of a gee or so of gravity? From the point of view of building structures, it's a boon. You have enough gravity to keep stuff in place, and allow conventional building techniques (unlike in orbit), but you can make your trusses and beams slimmer, 'cause they don't have to carry as much weight. You can build out of polystyrene instead of steel, so to speak.
Furthermore, from the pressure point of view, you only have to keep 1 atm of good stuff (breathable air) in, and a few small leaks just mean you need to replenish your air faster, whereas on Venus you need to keep 90 atom of bad stuff (highly toxic air) out, and small leaks mean corrosive poison gas in your breathing air. Ugh.
Not to mention on Mars you can see what you're doing, communicate to orbit with lasers, do a little astronomy, and enjoy the night-time sky, while on Venus you live at the bottom of the worst possible eternal gray pea-soup fog.
Finally, people think there might be life left on Mars, and there's certainly little doubt if we brought life with us it could survive there, while Venus is just completely intolerable to life due to the extreme temperatures.
That's not to say Mars doesn't have problems. The biggest, I suggest, is actually radiation, since Mars has no ozone layer to shield against UV, and no magnetic field to speak of to shield against cosmic rays. You'd not want to stand under the open sky on Mars for very long without good radiation shielding, I think.
In fact, spacecraft have a lot of trouble keeping cool in space. For example, from this article on the integrated trusses that are part of the Space Station:
When deployed both [trusses] have a set of three radiators that is about the size of a tennis court. Each set of radiators has the cooling capacity to chill four 2,000 square-foot houses on a hot summer day and consumes the equivalent power used to cool and light eight houses.
The reason for needing this kind of effort to cool the Space Station, even thought it's in the "very cold" environment of space, is that while the temperature of space is very low, the thermal capacity of space is also very low. That is, there's just very, very little of any cold matter around to which you can transfer heat, the way your body transfers heat to winter air when you step outside in December. You can radiate heat as infrared radiation, of course, but to be efficient this requires a lot of surface area for the volume being cooled. And yet, of course, when you build spaceships you tend to want to minimize the surface area for a given volume -- i.e. build compact shapes.
Furthermore, in space the wretched Sun is radiating huge gobs of light and heat at you 24 hours a day. Got to get rid of that, too.
You make a good argument, but I'd like to add a qualification. I'm not sure the availability of energy itself is a problem with Venus. More than enough energy for any conceivable terraforming rains down on Venus from the Sun. And it's quite usable energy, since its temperature is close to that of the solar photosphere (5500K). Thermodynamically speaking, you can run some very efficient heat engines between a hot reservoir at 5500K and a cold reservoir at even the high temperatures of Venus (300-700K, depending on altitude).
So the energy is there. But it isn't necessarily easy to use. The only plausible scenario probably remains some kind of biological seeding, i.e. designing some kind of photosynthesizing microbial life that can suck up all that CO2 and convert it to carbonate rock, as such life is thought to have done in the early history of the Earth, which is where our CO2 went and why we have great beds of limestone in the crust.
But I believe the problem with this is that there is very little water in the Venusian atmosphere, and all the microbial life we know about needs water. Furthermore, such a seeding process would not be quick -- at a minimum, millions of years are necessary -- and it might be hard to put the brakes on at the end.
Re:Would that also mean they had fillings?
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Stone Age Dentists
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Hmm, now that you mentinon it -- I'm beginning to have my doubts. Maybe I don't doubt myself...er...wait...
Well, you're right, so that's why I said the odds are against finding an ancient civilization near ours. But I don't think it's anywhere near impossible.
I'm not sure much of what we've built would survive 50 million years. That's an awful long time. Continents move, climate changes, mountain ranges are uplifted and eroded down, rivers change course, seas are formed and dry up again. Your typical 50 million year old strata is 50 to 100 feet down, I believe. So those artifacts would be whatever survives being compressed into 100 feet of sedimentary rock. Not a lot.
Stuff on the Moon would last, of course. But how easy would it be to find? The Moon's a big place. Maybe we'll only come across another Tranquility Base in 150 years or so, when all the Moon's nooks and crannies get explored. Not likely, no. But it's possible.
Hey, thanks for the insider's perspective. It was very interesting reading. One of the reasons I enjoy/. at random moments.
As a taxpayer and space enthusiast from the Apollo days, I'm not that unhappy with government and NASA. I figure they do pretty much as best as they can, given what Congress and by extension we the people tell 'em to do.
Now I'm older, and have experienced more government for myself, I think maybe it just has to go into private hands. You need someone like Musk or Branson at the top, someone with a driving passion and vision, to keep things moving and organized, and to encourage appropriate risks. Some of those guys will crash and burn, but some will succeed, and then we all win. I hope it works out, I really do. I always thought I'd maybe get a chance to take a trip to the Moon -- it seemed a cinch when I was 10 and watching Apollo 17 lift off. Now....well, maybe my son will get to go. I'd like that.
Re:Would that also mean they had fillings?
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Stone Age Dentists
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· Score: 1
I agree it's unlikely, but I don't think it's as very unlikely as you said. Even in the 2500 years for which we have decent records, civilization has seemed at times to advance and recede. It's been suggested by perfectly sober historians, for example, that the life of a Roman citizen of New Carthage (modern Cartagena) in 100 AD was much closer to modern life, in terms of public hygiene, literacy and education, and the sophistication of urban life, than was the life of a English subject in 16th century London.
If we can experience these kinds of fluctuations over a mere 2500 years, why not much larger fluctuations over periods of, say, 200,000 years? Fluctuations in which civilization advances to a modern equivalent (or further) and then collapses? How would we know? Artifacts? We have explored archaelogically very little of the Earth's surface, and mostly only where we already have reasons to suspect interesting stuff is buried. Further, consider that almost the entire temperate zone of the Earth has been ground down by glaciers several times in the last 250,000 years. We could never expect to find ruined cities, a la Planet of the Apes. Is it likely we could have missed noticing the 200,000-year-old artifacts of a global civilization? No. But is it impossible? Perhaps not.
We can open the door a smidge further -- we know there was, at one time, at least one other hominid species that we drove extinct, Homo neanderthalis. Why not others? Maybe 50 million years ago there was an intelligent, tool-using hominid much like ourselves, who rose to form a mighty civilization and then destroyed himself, or merely degenerated and went extinct. After 50 million years very little in the way of artifacts would've survived. Heck, of all the brontosaurs that ever roamed the planet -- surely a number in the billions -- we've only found the preserved skeletons of a dozen or so.
Both companies make civilian aircraft and rockets, and both do defense contracting.
Sure, and both have vowels in their corporate name, and both are run by men who wear pants to work and not togas. But on what many see as the key point of whether a company is willing to try radically new and different ways of getting into space, ways independent of the heavy hand of NASA bureaucratic design requirements -- and this is the "independent" I suspect the OP meant -- they're as different as chalk and cheese.
Boeing, like all aerospace majors, has tended to be very cautious about space vehicle design, perhaps in part simply because the cost-plus nature of major NASA and DoD contracts has meant there's less incentive to innovate. Why try some weird new design that may fail if the same old boring design, just multiplied by sixty, will work fine? So what if costs $bazillions? Your profit margin is guaranteed no matter how bloated the budget gets. And that does not even get into micromanagement by Congress, changing the mission requirements every 9 months at random, and institutional conservatism in NASA/DoD.
What many people hope is that a small company that is independent of this process, in the sense that they don't have any long history with the Feds, or gigantic conventional-warfare contracts to preserve, can be more innovative, and break the apparent barrier to lowering access to space costs that seems to have solidified in the past 20 years. It seems to these people incredible that it costs no less (or at least not much less) to put x pounds in orbit in 2006 than it did in 1969. They suggest it arises from fossilization in the big aerospace industry, fused with too-close a relationship to NASA/DoD, who are themselves paralyzed by the fickleness of Congress' support and the lack of any clear vision from the President.
Whether this is a true diagnosis of the situation remains to be seen, and people like Scaled, SpaceX, X-Cor, Virgin Galactic, et cetera will prove it one way or the other fairly soon.
Eh, let us not wildly exaggerate the pain involved. My father had all his fillings as a child without anaesthesia. It isn't unheard of for people to refuse it today.
What I find more curious about this report is that the ancient men were observant enough to realize that if you stopped the decay by drilling it out, you needn't lose the tooth later. As late as the 18th century or so, I believe the standard treatment for a decaying tooth was: (1) wait until it really starts to hurt, and then (2) pull it out. Drilling the decay out (while preserving the tooth) is a lot more sophisticated.
Well, the obvious problem with this theory is the the problem that bedeviled all pre-quantum theories of the Sun's composition: why is the Sun still glowing? It's easy enough to work out the energy lost by the Sun every year, and calculate how long it could stay as hot as it is given that energy loss, and given any particular mechanism of energy generation.
The problem, as previous generations discovered, is that no chemical energy-producing reaction whatsoever can produce enough energy for the Sun to still be hot after even a few million years (and eighteenth-century fossil and geological evidence had already established that the Earth, and hence the Solar System, must be at least several million years old). Could the energy come from gravitational collapse? Yes, surely. But, again, without a steady replenishing source, that energy lost through radiation would have cooled the Sun down long ago.
No pre-nuclear theory of the Sun was able to explain how the Sun could be simultaneously as old as the Earth and yet still hot. It was one of the big "aha!" moments in atomic physics when it was realized early in the 20th century that nuclear reactions could provide enough power to keep the Sun hot for billions of years.
If one accepts that nuclear fusion powers the Sun, however, then the central temperature of the Sun must be in the millions of degrees. Which means there can be no solid surface.
It's for this reason that the person after the link invokes weird, as-yet undiscovered means of stupendous energy generation to power the Sun. Fair enough. But until evidence of these undiscovered exceedingly high energy mechanisms is provided, all the observational evidence in the world hinting at a solid surface has to be regarded as dubious. It's as if I saw a film of Sasquatch walking on water. It's not the existence of Sasquatch per se that would make me doubt the film, but rather the impossibility of him walking on water. In the same way, it's not the observational evidence that convinces us the Sun has no solid surface, but the fact that this would be completely inconsistent with the only way we know it could be powered.
It's worth noting that differing isotope ratios are quite difficult to explain. Nuclear reactions must be involved, because no* chemical or physical process can distinguish between the different isotopes of an element. That is, there is no way the isotope ratio in lunar soil can be different from Earth soil unless the material that makes them up has undergone different types of nuclear reactions.
----------- * OK, almost no. I don't want to hear from any isotope-effects people. Anyway, you folks look for results in the 3rd or 4th decimal place and you know it.
Pain in the ass for whom? For entrepreneurs and engineers, trying to bring a great idea to market, and reap the rewards of their ingenuity? Sure. For lawyers and judges and Congress, the first of whom collect giant fees for litigating for and against patents, the second of whom revels in the glorious power of being able to decide the fate of millions, and the third of whom rolls in fat campaign contributions from all sides in the debate? Ha ha.
Don't look for lawyers to reform our legal system. Pigs might as well petition wolves to consider the virtues of turning vegetarian. Lawyers like the legal system the way it is -- confusing, capricious and expensive -- because if it ever were simplified to the point where normal sensible people could reliably predict its outcomes and use it themselves without risking immolation or poverty -- why, where would the necessity go for paying lawyers $400-$500 per hour salaries?
I'm not trying to be overly cynical here. Just pointing out that Congress on its own will never salvage the situation until angry citizens point the gun (of electoral defeat) at their heads and make them.
Can't say that I agree. In the first place, about forty of the 130 or so known interstellar molecules are as big or bigger than methanol. In the second place, methanol is readily formed in a reducing environment, such as you'd find in hydrogen-rich interstellar space. Third, while it is true that the formation reaction rate would be low, because as you point out the interstellar gas density is low, it is equally true that it's got billions of years to react. Remember how easily Stanley Miller got amino acids to form in a primordial soup with a little electrical discharge? Frankly, I'd be shocked if simple organics didn't form in a reducing, cryogenic environment with plenty of high-energy photons swimming about.
On earth we need dense solutions with a heat source to get a reaction to happen.
Not always, no. Plenty of reactions will go without heat, and in dilute solution.
if you mix oxygen and methane together in an attempt to get methanol, you'll get the lower-energy products of carbon monoxide, carbon dioxide and water.
To be sure. But that is a highly oxidizing environment, and hydrogen-rich interstellar space is a highly reducing environment. Surely most oxygen in a hydrogen-rich molecular cloud is going to be present as H2O, not O2, and then
CH3 + H2O -> CH3OH + 1/2 H2
would happens readily enough in a highly energetic environment. Interstellar space is an unusual chemical environment from the point of view of Earthlings, used as we are to living at the bottom of a pool of potent oxidizer. It's highly nonthermal and highly reducing. Our Earth-based chemistry instincts may not necessarily be a good guide.
Garage full of snowblowers, canoes without paddles, bicycle wheels without tires, and faded burnt-orange college-era furniture the wife won't allow in the house, eh?
Methanol (sporting a mere 6 atoms) is an "organic" molecule in the sense of being related to the chemistry of life only by courtesy, because it's got a carbon atom. I suggest information about how methanol is distributed between the stars will have as much relevance to the origin of life as knowing how helium or hydroxyl radicals or plain old dust is distributed. Which is to say, not much.
Of course you're right, not everybody is like the OP, but I think it's very likely most people are. When one is young, perhaps, then being an apostle or revolutionary is attractive. But most folks are not young, they're grumpy middle-aged folks just muddlin' through, and they lost interest in signing up for a Crusade long ago. (If for no other reason than that by the time they hit age 35 or so they've got their own philosophy and aren't interested any longer in being someone's disciple.)
For reg'lar folks, then, I suspect the attraction of any product, from an operating system to a car or system of government, is pretty much determined by its usefulness. It gets the job done, or it doesn't. Whether it has lovely philosophical decorations on it is a minor issue. Might be a tie-breaker if all other things are equal, but that's about it.
I suppose this may seem to suggest that most people are boring and unimaginative, but I only mean to suggest they are practical. And that's a useful trait. (John Rich put it well: If everybody contemplates the infinite instead of fixing the drains, many of us will die of cholera.)
RMS himself is sort of an illustration of the dangers of spending your life contemplating perfection. After GCC and friends he seems to have spent a decade or so pursuing the über-OS and getting nothing much actually done. If Linus hadn't come along and short-circuited this Zen contemplation by just building an actual OS, accepting whatever warts and compromises were necessary at that stage to get the damn thing done, then I think there's an excellent chance the GNU project would have become a curiousity in the software museum. Without Linus' decision to value practicality (a working OS) over philosophy (the perfect OS) the open-software movement might have been stillborn in the late 80s.
Slashdot Mirror
Don't forget it's a reversed (negative) image, so Xena itself is dark and the background of space is white.
I think if you look very closely you can see a few faint stars in the background...
One good measure is the thermodynamic efficiency. This is the maximum theoretical fraction of a given amount of heat that can be converted to useful work, and it's just given by 1 - Tc/Th, where Th is the temperature of your source of heat and Tc is the temperature of your sink (where the heat goes). You can see that if you have no temperature difference at all (Tc == Th) you get an efficiency of zero, and if you have either an infinitely hot heat source (Th -> inf) or an infinitely cold heat sink (Tc -> 0) you get perfect efficiency and can transform heat to work perfectly. Reality is, of course, in between.
Incidentally, the reason you need both a heat source and a heat sink is that it is the flow of heat that you can tap to do work, like you can sink a waterwheel into a rushing stream, or like you can put a lamp or other electrical device into a flow of electrons.
It's not quite the quality of the heat per se that matters, then, but the quality of the heat flow, captured in the difference in temperature. It's like the drop in water height that you tap for a hydroelectric plant, or a voltage drop across a battery -- the larger the drop, the better.
One of the reasons solar power is a good source of useful energy is because the effective temperature of sunlight is equal to the temperature of the sun's surface -- about 5500K. That's very high. Any engine, such as a photosynthesizing plant, that takes energy from sunlight and uses ambient air (300K) as the heat sink can be very efficient.
Uh, if the men are from Mars and the women from Venus, how did they end up here on Earth? Possibly each was sent here by whoever else lives on Mars and Venus, respectively.
Apparently we humans are rejects from two worlds...
But...why is having roughly 1g of gravity worth the enormous trouble of coping with pressures comparable to those at the bottom of the ocean? And temperatures so high in a corrosive atmosphere that only special and expensive building materials could stand it?
What's wrong with having only a third of a gee or so of gravity? From the point of view of building structures, it's a boon. You have enough gravity to keep stuff in place, and allow conventional building techniques (unlike in orbit), but you can make your trusses and beams slimmer, 'cause they don't have to carry as much weight. You can build out of polystyrene instead of steel, so to speak.
Furthermore, from the pressure point of view, you only have to keep 1 atm of good stuff (breathable air) in, and a few small leaks just mean you need to replenish your air faster, whereas on Venus you need to keep 90 atom of bad stuff (highly toxic air) out, and small leaks mean corrosive poison gas in your breathing air. Ugh.
Not to mention on Mars you can see what you're doing, communicate to orbit with lasers, do a little astronomy, and enjoy the night-time sky, while on Venus you live at the bottom of the worst possible eternal gray pea-soup fog.
Finally, people think there might be life left on Mars, and there's certainly little doubt if we brought life with us it could survive there, while Venus is just completely intolerable to life due to the extreme temperatures.
That's not to say Mars doesn't have problems. The biggest, I suggest, is actually radiation, since Mars has no ozone layer to shield against UV, and no magnetic field to speak of to shield against cosmic rays. You'd not want to stand under the open sky on Mars for very long without good radiation shielding, I think.
The reason for needing this kind of effort to cool the Space Station, even thought it's in the "very cold" environment of space, is that while the temperature of space is very low, the thermal capacity of space is also very low. That is, there's just very, very little of any cold matter around to which you can transfer heat, the way your body transfers heat to winter air when you step outside in December. You can radiate heat as infrared radiation, of course, but to be efficient this requires a lot of surface area for the volume being cooled. And yet, of course, when you build spaceships you tend to want to minimize the surface area for a given volume -- i.e. build compact shapes.
Furthermore, in space the wretched Sun is radiating huge gobs of light and heat at you 24 hours a day. Got to get rid of that, too.
You make a good argument, but I'd like to add a qualification. I'm not sure the availability of energy itself is a problem with Venus. More than enough energy for any conceivable terraforming rains down on Venus from the Sun. And it's quite usable energy, since its temperature is close to that of the solar photosphere (5500K). Thermodynamically speaking, you can run some very efficient heat engines between a hot reservoir at 5500K and a cold reservoir at even the high temperatures of Venus (300-700K, depending on altitude).
So the energy is there. But it isn't necessarily easy to use. The only plausible scenario probably remains some kind of biological seeding, i.e. designing some kind of photosynthesizing microbial life that can suck up all that CO2 and convert it to carbonate rock, as such life is thought to have done in the early history of the Earth, which is where our CO2 went and why we have great beds of limestone in the crust.
But I believe the problem with this is that there is very little water in the Venusian atmosphere, and all the microbial life we know about needs water. Furthermore, such a seeding process would not be quick -- at a minimum, millions of years are necessary -- and it might be hard to put the brakes on at the end.
Hmm, now that you mentinon it -- I'm beginning to have my doubts. Maybe I don't doubt myself...er...wait...
Well, you're right, so that's why I said the odds are against finding an ancient civilization near ours. But I don't think it's anywhere near impossible.
I'm not sure much of what we've built would survive 50 million years. That's an awful long time. Continents move, climate changes, mountain ranges are uplifted and eroded down, rivers change course, seas are formed and dry up again. Your typical 50 million year old strata is 50 to 100 feet down, I believe. So those artifacts would be whatever survives being compressed into 100 feet of sedimentary rock. Not a lot.
Stuff on the Moon would last, of course. But how easy would it be to find? The Moon's a big place. Maybe we'll only come across another Tranquility Base in 150 years or so, when all the Moon's nooks and crannies get explored. Not likely, no. But it's possible.
Ah, perhaps you mean like this.
Hey, thanks for the insider's perspective. It was very interesting reading. One of the reasons I enjoy /. at random moments.
As a taxpayer and space enthusiast from the Apollo days, I'm not that unhappy with government and NASA. I figure they do pretty much as best as they can, given what Congress and by extension we the people tell 'em to do.
Now I'm older, and have experienced more government for myself, I think maybe it just has to go into private hands. You need someone like Musk or Branson at the top, someone with a driving passion and vision, to keep things moving and organized, and to encourage appropriate risks. Some of those guys will crash and burn, but some will succeed, and then we all win. I hope it works out, I really do. I always thought I'd maybe get a chance to take a trip to the Moon -- it seemed a cinch when I was 10 and watching Apollo 17 lift off. Now....well, maybe my son will get to go. I'd like that.
I doubt everybody. Even myself.
I agree it's unlikely, but I don't think it's as very unlikely as you said. Even in the 2500 years for which we have decent records, civilization has seemed at times to advance and recede. It's been suggested by perfectly sober historians, for example, that the life of a Roman citizen of New Carthage (modern Cartagena) in 100 AD was much closer to modern life, in terms of public hygiene, literacy and education, and the sophistication of urban life, than was the life of a English subject in 16th century London.
If we can experience these kinds of fluctuations over a mere 2500 years, why not much larger fluctuations over periods of, say, 200,000 years? Fluctuations in which civilization advances to a modern equivalent (or further) and then collapses? How would we know? Artifacts? We have explored archaelogically very little of the Earth's surface, and mostly only where we already have reasons to suspect interesting stuff is buried. Further, consider that almost the entire temperate zone of the Earth has been ground down by glaciers several times in the last 250,000 years. We could never expect to find ruined cities, a la Planet of the Apes. Is it likely we could have missed noticing the 200,000-year-old artifacts of a global civilization? No. But is it impossible? Perhaps not.
We can open the door a smidge further -- we know there was, at one time, at least one other hominid species that we drove extinct, Homo neanderthalis. Why not others? Maybe 50 million years ago there was an intelligent, tool-using hominid much like ourselves, who rose to form a mighty civilization and then destroyed himself, or merely degenerated and went extinct. After 50 million years very little in the way of artifacts would've survived. Heck, of all the brontosaurs that ever roamed the planet -- surely a number in the billions -- we've only found the preserved skeletons of a dozen or so.
Both companies make civilian aircraft and rockets, and both do defense contracting.
Sure, and both have vowels in their corporate name, and both are run by men who wear pants to work and not togas. But on what many see as the key point of whether a company is willing to try radically new and different ways of getting into space, ways independent of the heavy hand of NASA bureaucratic design requirements -- and this is the "independent" I suspect the OP meant -- they're as different as chalk and cheese.
Boeing, like all aerospace majors, has tended to be very cautious about space vehicle design, perhaps in part simply because the cost-plus nature of major NASA and DoD contracts has meant there's less incentive to innovate. Why try some weird new design that may fail if the same old boring design, just multiplied by sixty, will work fine? So what if costs $bazillions? Your profit margin is guaranteed no matter how bloated the budget gets. And that does not even get into micromanagement by Congress, changing the mission requirements every 9 months at random, and institutional conservatism in NASA/DoD.
What many people hope is that a small company that is independent of this process, in the sense that they don't have any long history with the Feds, or gigantic conventional-warfare contracts to preserve, can be more innovative, and break the apparent barrier to lowering access to space costs that seems to have solidified in the past 20 years. It seems to these people incredible that it costs no less (or at least not much less) to put x pounds in orbit in 2006 than it did in 1969. They suggest it arises from fossilization in the big aerospace industry, fused with too-close a relationship to NASA/DoD, who are themselves paralyzed by the fickleness of Congress' support and the lack of any clear vision from the President.
Whether this is a true diagnosis of the situation remains to be seen, and people like Scaled, SpaceX, X-Cor, Virgin Galactic, et cetera will prove it one way or the other fairly soon.
Eh, let us not wildly exaggerate the pain involved. My father had all his fillings as a child without anaesthesia. It isn't unheard of for people to refuse it today.
What I find more curious about this report is that the ancient men were observant enough to realize that if you stopped the decay by drilling it out, you needn't lose the tooth later. As late as the 18th century or so, I believe the standard treatment for a decaying tooth was: (1) wait until it really starts to hurt, and then (2) pull it out. Drilling the decay out (while preserving the tooth) is a lot more sophisticated.
Well, the obvious problem with this theory is the the problem that bedeviled all pre-quantum theories of the Sun's composition: why is the Sun still glowing? It's easy enough to work out the energy lost by the Sun every year, and calculate how long it could stay as hot as it is given that energy loss, and given any particular mechanism of energy generation.
The problem, as previous generations discovered, is that no chemical energy-producing reaction whatsoever can produce enough energy for the Sun to still be hot after even a few million years (and eighteenth-century fossil and geological evidence had already established that the Earth, and hence the Solar System, must be at least several million years old). Could the energy come from gravitational collapse? Yes, surely. But, again, without a steady replenishing source, that energy lost through radiation would have cooled the Sun down long ago.
No pre-nuclear theory of the Sun was able to explain how the Sun could be simultaneously as old as the Earth and yet still hot. It was one of the big "aha!" moments in atomic physics when it was realized early in the 20th century that nuclear reactions could provide enough power to keep the Sun hot for billions of years.
If one accepts that nuclear fusion powers the Sun, however, then the central temperature of the Sun must be in the millions of degrees. Which means there can be no solid surface.
It's for this reason that the person after the link invokes weird, as-yet undiscovered means of stupendous energy generation to power the Sun. Fair enough. But until evidence of these undiscovered exceedingly high energy mechanisms is provided, all the observational evidence in the world hinting at a solid surface has to be regarded as dubious. It's as if I saw a film of Sasquatch walking on water. It's not the existence of Sasquatch per se that would make me doubt the film, but rather the impossibility of him walking on water. In the same way, it's not the observational evidence that convinces us the Sun has no solid surface, but the fact that this would be completely inconsistent with the only way we know it could be powered.
It's worth noting that differing isotope ratios are quite difficult to explain. Nuclear reactions must be involved, because no* chemical or physical process can distinguish between the different isotopes of an element. That is, there is no way the isotope ratio in lunar soil can be different from Earth soil unless the material that makes them up has undergone different types of nuclear reactions.
-----------
* OK, almost no. I don't want to hear from any isotope-effects people. Anyway, you folks look for results in the 3rd or 4th decimal place and you know it.
Pain in the ass for whom? For entrepreneurs and engineers, trying to bring a great idea to market, and reap the rewards of their ingenuity? Sure. For lawyers and judges and Congress, the first of whom collect giant fees for litigating for and against patents, the second of whom revels in the glorious power of being able to decide the fate of millions, and the third of whom rolls in fat campaign contributions from all sides in the debate? Ha ha.
Don't look for lawyers to reform our legal system. Pigs might as well petition wolves to consider the virtues of turning vegetarian. Lawyers like the legal system the way it is -- confusing, capricious and expensive -- because if it ever were simplified to the point where normal sensible people could reliably predict its outcomes and use it themselves without risking immolation or poverty -- why, where would the necessity go for paying lawyers $400-$500 per hour salaries?
I'm not trying to be overly cynical here. Just pointing out that Congress on its own will never salvage the situation until angry citizens point the gun (of electoral defeat) at their heads and make them.
I recall "It's Hard To Fondle Penguins."
Sorry, that should be:
CH4 + H2O -> CH3OH + H2
I feel like a Yorkshireman, losing H's like this...
Can't say that I agree. In the first place, about forty of the 130 or so known interstellar molecules are as big or bigger than methanol. In the second place, methanol is readily formed in a reducing environment, such as you'd find in hydrogen-rich interstellar space. Third, while it is true that the formation reaction rate would be low, because as you point out the interstellar gas density is low, it is equally true that it's got billions of years to react. Remember how easily Stanley Miller got amino acids to form in a primordial soup with a little electrical discharge? Frankly, I'd be shocked if simple organics didn't form in a reducing, cryogenic environment with plenty of high-energy photons swimming about.
On earth we need dense solutions with a heat source to get a reaction to happen.
Not always, no. Plenty of reactions will go without heat, and in dilute solution.
if you mix oxygen and methane together in an attempt to get methanol, you'll get the lower-energy products of carbon monoxide, carbon dioxide and water.
To be sure. But that is a highly oxidizing environment, and hydrogen-rich interstellar space is a highly reducing environment. Surely most oxygen in a hydrogen-rich molecular cloud is going to be present as H2O, not O2, and then
CH3 + H2O -> CH3OH + 1/2 H2
would happens readily enough in a highly energetic environment. Interstellar space is an unusual chemical environment from the point of view of Earthlings, used as we are to living at the bottom of a pool of potent oxidizer. It's highly nonthermal and highly reducing. Our Earth-based chemistry instincts may not necessarily be a good guide.
Garage full of snowblowers, canoes without paddles, bicycle wheels without tires, and faded burnt-orange college-era furniture the wife won't allow in the house, eh?
Well, check this out, then.
'56 Corvette. The second set of barrels on the dual carburetors don't even open until 60-70 MPH.
Methanol (sporting a mere 6 atoms) is an "organic" molecule in the sense of being related to the chemistry of life only by courtesy, because it's got a carbon atom. I suggest information about how methanol is distributed between the stars will have as much relevance to the origin of life as knowing how helium or hydroxyl radicals or plain old dust is distributed. Which is to say, not much.
Not everybody is like you.
Of course you're right, not everybody is like the OP, but I think it's very likely most people are. When one is young, perhaps, then being an apostle or revolutionary is attractive. But most folks are not young, they're grumpy middle-aged folks just muddlin' through, and they lost interest in signing up for a Crusade long ago. (If for no other reason than that by the time they hit age 35 or so they've got their own philosophy and aren't interested any longer in being someone's disciple.)
For reg'lar folks, then, I suspect the attraction of any product, from an operating system to a car or system of government, is pretty much determined by its usefulness. It gets the job done, or it doesn't. Whether it has lovely philosophical decorations on it is a minor issue. Might be a tie-breaker if all other things are equal, but that's about it.
I suppose this may seem to suggest that most people are boring and unimaginative, but I only mean to suggest they are practical. And that's a useful trait. (John Rich put it well: If everybody contemplates the infinite instead of fixing the drains, many of us will die of cholera.)
RMS himself is sort of an illustration of the dangers of spending your life contemplating perfection. After GCC and friends he seems to have spent a decade or so pursuing the über-OS and getting nothing much actually done. If Linus hadn't come along and short-circuited this Zen contemplation by just building an actual OS, accepting whatever warts and compromises were necessary at that stage to get the damn thing done, then I think there's an excellent chance the GNU project would have become a curiousity in the software museum. Without Linus' decision to value practicality (a working OS) over philosophy (the perfect OS) the open-software movement might have been stillborn in the late 80s.