I don't think Russia is so much of an idiot as to give the Kurds anti-aircraft systems. Because Turkey would respond by giving the FSA anti-aircraft systems. Which would be far more devastating due to how close the Russian airbase near Latakia is to opposition troops and how Russia's been focusing so much on close air support, as well as the ratios of assets in the region that could be employed if necessary (Turkey and the other coalition states have far, far more)
Russia's also at real risk of facing a heavy dose of irony. As the battle front has spread deeper into Latakia (yes, Russia/Iran/Hezbollah/Assad has lost ground in Assad's heartland since the Russian/Iranian surge) it's increasingly violent in Jabal al-Turkuman, aka the Turkman Mountains, aka an area to a large indigenous Turkic population. The Russian strikes there have stirred up anger in Turkey (probably no doubt a contributor to Turkey being a bit more trigger-happy on their antiaircraft missiles than usual), and in recent days pictures have started emerging of members of far-right parties in Turkeys that have crossed over to Syria and taken up arms. This has the potential to involve into a mirror of the situation in Donbas.
BTW, and back to the original topic - why are so few people covering the helicopter downing in Syria? Look it up: one of the helicopters in Latakia on search and rescue mission for the plane crew went down. The rebels say that they hit it with a TOW. Russia says that it underwent a "hard landing", but that the crew is okay.
Oh, and we still have Israel continuing to be a wildcard, having launched several strikes inside Syria again just the other day, in the heels of last week's attack on the Damascus airport. They seem determined to stop Iran and Russia from transferring advanced weapons to Hezbollah at any cost.
There have been tons of reasons proposed for how it works. Given that its thrust seems to track its temperature, not the power being supplied to it, it's clearly a thermal effect. And there are much better ways to make rockets driven by thermal effects.
I'm amazed that there are still people talking about this thing here.
I imagine Rei standing next to the Wright brothers and claiming that not only will their idea not work...
Huh? Your analogy maps to me saying that rockets don't work. Is that what you actually think I was writing?
And EM Drives? When you stand in the same room as the several PhDs that are investigating and tell them to their face...
You can also find Ph.Ds investigating psychic abilities, ghosts, and so on down the line. The fact that there exist people on the planet who managed to write a doctoral thesis about something does not mean that they're working on something that the vast majority of the scientific community thinks is pathological science.
All of that is vastly more impractical than the current minimalist Mars mission concepts. We can't scrounge up the funding for one of them, and you want to build something vastly larger?
Magnetic shields are good for preventing solar radiation but do little against GCR. You still need physical shielding sufficient to block GCR - which is harder to block anyway, aka, you still need significant shielding.
You - and TFA - mentioning growing crops is naive. The reason that all serious baseline approaches only call for small, experimental-level (rather than sustinance-level) crop growing is because A) that's way too much risk (starvation due to crop failure, which is tough enough to prevent here on Earth from thousands of different causes, yet alone in a radically different environment) to impose on an early mission, and B) shipping in the food to last for a typical mission duration is actually lighter than the cost of shipping in a facility large enough to grow that much food and the associated power and environmental systems required to operate it. The ability to grow crops would be important for long-term habitations (which is why NASA is researching it - although the plant growth experiment designed for the Mars 2020 lander got cut), but the first missions to Mars absolutely will not be relying on it for any relevant portion of their calories.
VASIMR is not new. One however does need to remember the downside: any high ISP/moderate to high thrust system is inherently going to be consuming vast amounts of power. And producing vast amounts of power means vast amounts of cooling area. So while it's "possible" to power a ship like this, it also means a very large ship... which partially eliminates the reason why one would want such a craft in the first place. It's more important for space "tugs"/"ferries" which take many trips, and for outer-planets missions. And note that there are many alternatives to VASIMR.
And please, you do a discredit to yourself by adding "or those EM drives".
I think you're confused. They weren't "writing code to handle apostrophes". They wrote a code review-related microapp, and I noticed during the submission of a review that it failed, gave an detailed error message (which I should probably warn him is also bad practice, you don't help would-be hackers out by publicly such information) indicating a particular bad SQL statement, and the statement was "bad" because it wasn't sanitizing the apostrophes in my input. It was immediately clear that he was building his query through simple string concatenation.
The application was designed for internal usage (though I'm not sure if it was externally accessible)... but even if it wasn't externally accessible, the fact that he would write SQL queries through string concatenation is a problem, in case he ever would write an externally-accessible application for us. I'm not disappointed or upset with him or anything, because lots of people do that, it's a natural way for someone who doesn't realize the risks to do it. People are used to building up strings through concatenation - for example, for displaying text in a GUI. A large chunk of programmers just don't know the risks that exist in certain contexts.
Your stuff doesn't even exist. Why would anyone put a penny into some half-witted sci-fi-addled nerd's fantasies?
Because that's what you so kindly mentioned: "technology gets better". If you'd rather stick to using the same technology over and over while the easiest resources exhaust, that's otherwise known as committing yourself to ever-increasing resource prices.
I'm sorry, I wasn't aware we are tossing things into a black hole. Just as a reminder, once we extract things from the ground, they stay here. Merely transferred to garbage dumps or ship-breaking yards.
Lol, and you're the one complaining about naive fantasies? Sorry, but resource recovery is not, and never will be, 100% efficient. Or even particularly close to it, even with valuable materials. And due to the fact that the human population - and GDP per capita, which means more consumption - is ever growing, even if there was 100% efficiency you'd still need a continuous stream of new material.
After all, once you have this magical technology to mine asteroids, you can simply use it here,
How does that make even the most remote bit of sense? When did Earth become a gravityless body comprised entirely of absurdly-rich ore with no overburden which needs to export to... a different Earth?
We will find other, cheaper ways of doing it.
The fact that people currently pay for these minerals attests to the fact that people find paying these sorts of prices to be "the best way to do it".
It's quite possible, of course, that technology changes might change that picture in the future. However, it's just as possible that technology changes might cause a situation where the demand for these metals goes even higher. More often than not, rare metal demands increase over time with advancing technology, not decrease.
Like I said, ball-point pens and relay contacts aren't quite the business they were in 1965, old man.
I'm 35, female, and industrial consumption of platinum-group metals has dramatically increased since the 1960s, almost across the board.
We don't need to deploy any of your comic-book "science"
You know, you really need to make up your mind on your insults. Am I a little kid reading comic books or am I an old geezer obsessing over obsolete resources?
Anyway, you've made your maturity level pretty clear in this thread, so it's done. Goodnight!
Even older programmers do it - I discovered just last Friday that a senior programmer I work with had written a service that was vulnerable to SQL injection (purely by accident, I was using it and noticed how it was mishandling apostrophes).
I think most programmers will do it sooner or later until either they've A) internalized the warnings from others, or B) been caught by someone noticing (and potentially exploiting) vulnerable code that they've written. And if neither A) nor B) happen immediately, they may well be serial abusers.
Also a lot of programmers seem to forget that injection doesn't just apply to SQL. Shell command insertion is also a huge abuse target.
Yes, because one just goes out and adopts - it's not like it's a multiyear process, often full of heartbreak, to get a child who more likely than not will grow up with identity issues and spend a lot of time seeing you as "not their real parent". I've been a stepmother before. It was a pretty heartbreaking experience. You know, they start crying over something and you try to console them and they start crying I want my mommy, and you reassure them that you're there for them, and they start crying, no, *MY* mommy, my *REAL* mommy.... think I really want those sort of experiences ever again? Sorry, I've just been reading some articles written from people who were adopted as children, about their attitudes toward the whole thing, and it's turning me even more off of ever considering that route.
Surrogacy is at least a bit closer. But it's illegal here. Some people pretend that they had a child overseas, but they can be investigated over it. In most cases it means spending years having to try to adopt your own child - and meanwhile having no rights over anything at all related to them.
Not in the context of your space fantasies that would require billions up front, no.
Large mines on Earth also cost "billions upfront" - your point?
Technology gets better, remember?
While at the same time the easiest resources become exhausted. Also, "technology gets better" often means "exploiting radically new mineral sources that were previously unavailable to you".
We don't need osmium, or rhodium
Right, who needs extremely hard materials that tolerate very high wear? Who needs chemicals used in fingerprint detection and electron microscopy? Who needs extreme UV reflectors? Who needs catalytic converters and industrial catalysts? Who needs flat-panel glass? Who needs mammography filters? What useless garbage.
Forget about veins - even in bulk some S-type meteorites have been measured at over 100ppm platinum-group metals, several times better than the best mine on Earth (last I checked, about 40ppm), let alone typical mines for platinum-group metals on Earth, which range from a couple hundred ppb to a few ppm. Concerning precious metals as a whole, even the *average* H-chondrite is 28ppm precious metals. L-chondrites can be up to 220 ppm precious metals. And there's no overburden - it's rich all the way through. "Veins" or other areas of unusually high concentration would just be an extra.
One could eject raw ore to Earth or concentrate it first, through any number of steps (particularly if the surface is pulverized to regolith - metallic grains can be extracted through electromagnetic processes). The key is that you should be able to eject a sintered or cast projectile on an Earth-intercept trajectory without the use of any consumables - via a coilgun. If your projectiles include sufficient metallic material to sustain an induced magnetic field than they don't need any sort of sabot. If they're shaped and sized properly you can have a stable reentry with minimal ablative burnoff and remain relatively intact after impact (too small and they'll burnup too much; too large and they'll explode too much on impact)
Our system isn't as generous as yours (Iceland), but it's still worlds beyond what America offers (no paid leave, and only rather limited unpaid leave to mothers).
I'm of mixed feelings. On one hand, I think it's a great thing to do for parents and for the kids. On the other hand, as someone who's infertile, it's kind of frustrating. I never complain to anyone in person, absolutely not. But I see all of my coworkers in their 20s and 30s having one child after the next and spending a large chunk of their time on the job... off the job.... often taking their leave in vacation homes or overseas.... I mean, I understand why the time is given, I totally sympathize... but underneath it sort of feels unfair to people who can't have children, to have such a massive benefit for those who can.
Which means none of the tools and techniques we use here will work. Oh, and you'll need to fully automate them too.
As if we haven't been extensively working on both of those things already (staying grounded on low-gravity bodies and automating robotic systems - and no, "fully automated" is not needed, there's nothing preventing the use of ground controllers on Earth).
Wow, so we just need to wait a few years per "mission". Wow, yeah, that sounds useful.
So your conception is that one would only mine when an asteroid is near Earth? Whatever you mine and fire off may only impact earth a few years, but it doesn't change the throughput. Your returns all happen in clusters, but it's a lot of material at once.
"Regular shipments of absurdly valuable mineral concentrates"
Except that no minerals are "absurdly" valuable, and we are already living on a rock with the same minerals.
Gold, platinum, iridium, rhodium, osmium, indium and palladium hover in the rough ballpark of $10000-60000 USD per kilogram; gem-quality peridot about the same. You don't call that "absurdly valuable"? And those prices of earth-source materials, while those wanting them for luxury purposes (as opposed to industrial purposes) would pay significant premiums for space-sourced minerals.
Of course they're all "found" on Earth. But they're all found on Earth in tiny quantities, usually upper ppb/lower ppm-levels from ore in a good mine - underneath vast amounts of overburden.
You are a totally deluded child.
Wow, namecalling. That's surely a good way to make you totally not look like a child.
Moreover, the idea that there even are veins of material in asteroids enhanced in various elements is less than certain. It seems to me that most of the differentiating processes that result in "loads" with high concentrations of minerals on Earth probably wouldn't be present in asteroids.
That's an overly simplistic view of asteroids. First off, we already know very well from spectroscopy that asteroids sometimes (if not usually) have varied surface material properties. Hence it seems perfectly reasonable to expect certain areas to be more or less enriched in various minerals. It's also an overly simplistic view to think of the entire body of an asteroid as being undifferentiated; asteroids have suffered being pounded by fierce impacts since the formation of our solar system, which means melt, and melt can mean differentiation - albeit localized. Lastly, there are asteroids (the largest being 16 Psyche) thought to be remnants of the cores of larger bodies. So mining them would be more like mining chunks of Earth's core - primarily nickel/iron but highly rich in heavy elements rare on Earth's surface.
We surely can see how and why. Asteroids have (generally) tiny gravitational fields. By and large, the delta-V needed to return material from an asteroid to Earth is just its earth-intercept delta-V. Which on some asteroids - earth-crossers - this energy can be tiny itself. At earth, the body can either aerocapture or go all the way in for landing. Neither of these things require an engine. There is of course the heat load to deal with. Your projectiles can be ideally shaped for reentry and with the outer layer of the hot side expected to ablate off. If you want to go straight for landing you don't have to have a parachute, there's nothing living on it. Asteroids of a certain size survive landing mostly intact (too small and they mostly burn up; too large and they mostly convert themselves to gas and plasma on impact).
Things that would be needed:
* Impact area, large enough to account for aiming errors
* Mining probe which can "hop" around the body, boil off its surface, and condense it into a ceramic or tungsten mold - OR collect loose/grind off solid material and cast it with small amounts of a binding agent or sinter it.
* Power source for the casting process: concentrated solar, high-temperature nuclear, or battery (with periodic charging and/or cable to a base station, which in turn would be solar or nuclear)
* Coil gun and system to load it, along with the power to fire it.
* Standard probe hardware: communications, cameras, compute hardware, thermal management, etc.
Reward:
* Regular shipments of absurdly valuable mineral concentrates (rare metals, gems such as olivine/peridot (if not boiled during mining - it tolerates sintering), etc). A single multitonne-tonne rock recovered on the surface may be worth in the ballpark of $1m even ignoring the (probably significant) multiplier of it having come from space (aka, would your average luxury-obsessed sultan rather have table made of gold, or a table made of Gold From Space?).
The key issue is that excepting the option of using an imported binder, all of the above options require no regular shipments of any hardware from Earth except for that required by maintenance. Meaning that once you pay your (multi-billion-dollar) capital costs (largely imposed directly or indirectly by the rocket equation), the rocket equation ceases to be relevant.
Are we ready to launch something like that today? Of course not. In space you don't just launch multi-billion dollar projects without first including test hardware on smaller probes first to try out all of the difficult aspects of what you want to do, to retire the risk. But there are no fundamental technological or economic barriers. The value of the return materials is massive and they can be launched to earth intercept with little to no consumables via electric power.
I once worked for Rockwell-Collins in the states - I started there shortly after the NASA "incident". What incident? Apparently they were caught - after doing it for many years - billing everything to the shuttle, as a matter of corporate policy. Unlike most contracts Rockwell-Collins gets, there was no cap on the Shuttle project budget. So whenever any project ran over, they just billed the engineers' time to the Shuttle.;)
NASA does some great stuff in terms of R&D and robotic exploration. But their culture is not a good matchup for developing launch systems, whether in-house or through contractors.
Re:The real worry should be Kessler Syndrome
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Satellite Wars (ft.com)
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· Score: 4, Interesting
Even if sand was launched to LEO, it wouldn't have a long lifespan - the smaller the object, the higher its ratio of cross section to mass. And you don't have to launch into an orbital trajectory. And if you were really bothered, rather than launching sand one could launch grains of something that would sublimate in space.
The sand itself doesn't pose a long-term debris threat. Even the act of disabling a satellite doesn't inherently do so - so long as it remains by and large a single piece. However, sand grains piercing into, say, a pressurized hydrazine tank and detonating the satellite into chunks of shrapnel of various sizes, that's a very different issue.
Which would be a relevant comment if I was talking about some sort of imaginary alternative proposal where major powers planned to fire handguns at satellites, rather than what I was actually talking about, aka giving people a sense of the energies carried by grains of sand in orbit by comparing them to the energies of bullets fired on Earth.
Re:The real worry should be Kessler Syndrome
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Satellite Wars (ft.com)
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· Score: 4, Insightful
If two major powers (the kinds that have satellite constellations) are fighting, we have a lot more to worry about than Kessler Syndrome. Like, say, global thermonuclear annihilation.
Beam weapons are popular for their instant hit ability, but you have to have constant real-time tracking of the object (not simply a calculated trajectory), otherwise the tiniest vernier-thruster maneuver is enough to cause a miss. There's also a lot of potential countermeasures, both temporary (such as clouds of dust) and permanent (layered reflective foil skins).
If you don't need an instant hit then probably the most effective way is nothing more than a rocket full of sand. It's basically buckshot times tens of millions. If you launch opposite the direction of Earth's rotation (costs a couple thousand more m/s delta-V) you can get impact velocities in the ballpark of 15000+ m/s. A 5mg grain of sand would carry an impact force of 560 joules. By comparison, a 100mph fastball, an expert karate punch, and a professional golfer drive are all 150J. A.22LR leaves the muzzle of a gun with an energy of 168 joules, a.380 pistol with 245J, and a 9mm with 467J (again, remember that these are muzzle velocities, bullets lose energy quickly with distance). A grain of sand a satellite (aka, something that fundamentally has to be built lightweight) at 15000 m/s is just going to punch right through it. Tens of millions of them... well, you can't miss.
Also, small objects like grains of sand don't have long orbital lifespans. If you really wanted to you could fire them at a non-orbital trajectory as well. And they don't necessarily make what they hit explode, even if they punch right through it.
You joke, but there actually is a Pakistani children's show called Burqa Avenger about a burqa-wearing ninja who fights people that try to stop girls from getting an education.;)
One could take the joke from SATW and pit an arabian or south asian woman in a burqa against a Somali ship hijacker and get an epic Ninja vs. Pirate battle;)
Last I checked, non-nuclear grade had risen to around $500/kg and nuclear-grade about $1500/kg. But maybe it's changed since then, or maybe I'm remembering wrong.
Current blanket designs still end up using far more lithium than beryllium too
Not according to the last paper I read, they did optimization work on the blanket for ITER and found that a significantly higher percentage of beryllium than lithium yields a higher breeding rate. Same paper that covered that lead-based breeding is impractical for ITER. I have to run right now but I can dig it up for you later if you want.
Geothermal power is more on the order of 40 TW, which is not far from power used by humans, a little less than 20 TW.
Not when you include enhanced geothermal. Its potential dwarfs human consumption.
Geothermal is one of those technologies that keeps slowly advancing without anyone ever seeming to take notice. It's the most underhyped cleantech of them all, in a field that normally suffers from way too much hype. Ironically it's been "dirty" energy extraction that's been helping them - the drilling technology advancements made by oil and gas companies are usually directly applicable to geothermal as well.
And some of the discoveries are accidental. Here in Iceland at the Krafla power plant they accidentally drilled into a magma chamber. Magma backed up into their well dozens of meters before stopping. Big screwup, right? Well, unlike the only other time in history this has happened (Hawaii), they decided "what the heck" and tried turning it into a production well rather than just sealing it. And it not only worked, this one well now produces half of the plant's total power generation (30 of the 60 MW). Its production temperature is 450C, which is crazy-hot for geothermal. They're now planning to do it again on purpose.
That said, it still won't be "cheap". The lithium blanket will actually contain more beryllium than lithium, which will be consumed faster than the lithium - and beryllium is something like $1500/kg. Nothing like $30k/g, but not pocket change. It's a big initial cost because you need enough of it to form the initial blanket, which is very large. It's also expensive to work with due to its toxicity (although it's relatively safe when not in a dust/vaporizeable form)
They looked at using heavy metals like lead for neutron multiplication but it just didn't work out. They have a much higher rate of neutron multiplication at high energies, but beryllium's (n, 2n) reaction extends to significantly lower energies, and that turns out to be the most important range. The thing is, you have to have neutron multiplication - if you don't then you need to capture every last fusion neutron to breed the tritium needed to produce a replacement, which obviously isn't going to happen. It's not like fission which gives off a whole shower of them, you get the one 14,1 MeV neutron and that's it.
Slashdot Mirror
I don't think Russia is so much of an idiot as to give the Kurds anti-aircraft systems. Because Turkey would respond by giving the FSA anti-aircraft systems. Which would be far more devastating due to how close the Russian airbase near Latakia is to opposition troops and how Russia's been focusing so much on close air support, as well as the ratios of assets in the region that could be employed if necessary (Turkey and the other coalition states have far, far more)
Russia's also at real risk of facing a heavy dose of irony. As the battle front has spread deeper into Latakia (yes, Russia/Iran/Hezbollah/Assad has lost ground in Assad's heartland since the Russian/Iranian surge) it's increasingly violent in Jabal al-Turkuman, aka the Turkman Mountains, aka an area to a large indigenous Turkic population. The Russian strikes there have stirred up anger in Turkey (probably no doubt a contributor to Turkey being a bit more trigger-happy on their antiaircraft missiles than usual), and in recent days pictures have started emerging of members of far-right parties in Turkeys that have crossed over to Syria and taken up arms. This has the potential to involve into a mirror of the situation in Donbas.
BTW, and back to the original topic - why are so few people covering the helicopter downing in Syria? Look it up: one of the helicopters in Latakia on search and rescue mission for the plane crew went down. The rebels say that they hit it with a TOW. Russia says that it underwent a "hard landing", but that the crew is okay.
Oh, and we still have Israel continuing to be a wildcard, having launched several strikes inside Syria again just the other day, in the heels of last week's attack on the Damascus airport. They seem determined to stop Iran and Russia from transferring advanced weapons to Hezbollah at any cost.
Isn't it lovely to have a stalker who mentions you in threads even when you're not around? Everyone should have a stalker. :)
There have been tons of reasons proposed for how it works. Given that its thrust seems to track its temperature, not the power being supplied to it, it's clearly a thermal effect. And there are much better ways to make rockets driven by thermal effects.
I'm amazed that there are still people talking about this thing here.
Anyway, obligatory XKCD. And again.
Oh hey, it's my stalker from the other day.
Huh? Your analogy maps to me saying that rockets don't work. Is that what you actually think I was writing?
You can also find Ph.Ds investigating psychic abilities, ghosts, and so on down the line. The fact that there exist people on the planet who managed to write a doctoral thesis about something does not mean that they're working on something that the vast majority of the scientific community thinks is pathological science.
All of that is vastly more impractical than the current minimalist Mars mission concepts. We can't scrounge up the funding for one of them, and you want to build something vastly larger?
Magnetic shields are good for preventing solar radiation but do little against GCR. You still need physical shielding sufficient to block GCR - which is harder to block anyway, aka, you still need significant shielding.
You - and TFA - mentioning growing crops is naive. The reason that all serious baseline approaches only call for small, experimental-level (rather than sustinance-level) crop growing is because A) that's way too much risk (starvation due to crop failure, which is tough enough to prevent here on Earth from thousands of different causes, yet alone in a radically different environment) to impose on an early mission, and B) shipping in the food to last for a typical mission duration is actually lighter than the cost of shipping in a facility large enough to grow that much food and the associated power and environmental systems required to operate it. The ability to grow crops would be important for long-term habitations (which is why NASA is researching it - although the plant growth experiment designed for the Mars 2020 lander got cut), but the first missions to Mars absolutely will not be relying on it for any relevant portion of their calories.
VASIMR is not new. One however does need to remember the downside: any high ISP /moderate to high thrust system is inherently going to be consuming vast amounts of power. And producing vast amounts of power means vast amounts of cooling area. So while it's "possible" to power a ship like this, it also means a very large ship... which partially eliminates the reason why one would want such a craft in the first place. It's more important for space "tugs"/"ferries" which take many trips, and for outer-planets missions. And note that there are many alternatives to VASIMR.
And please, you do a discredit to yourself by adding "or those EM drives".
I think you're confused. They weren't "writing code to handle apostrophes". They wrote a code review-related microapp, and I noticed during the submission of a review that it failed, gave an detailed error message (which I should probably warn him is also bad practice, you don't help would-be hackers out by publicly such information) indicating a particular bad SQL statement, and the statement was "bad" because it wasn't sanitizing the apostrophes in my input. It was immediately clear that he was building his query through simple string concatenation.
The application was designed for internal usage (though I'm not sure if it was externally accessible)... but even if it wasn't externally accessible, the fact that he would write SQL queries through string concatenation is a problem, in case he ever would write an externally-accessible application for us. I'm not disappointed or upset with him or anything, because lots of people do that, it's a natural way for someone who doesn't realize the risks to do it. People are used to building up strings through concatenation - for example, for displaying text in a GUI. A large chunk of programmers just don't know the risks that exist in certain contexts.
Because that's what you so kindly mentioned: "technology gets better". If you'd rather stick to using the same technology over and over while the easiest resources exhaust, that's otherwise known as committing yourself to ever-increasing resource prices.
Lol, and you're the one complaining about naive fantasies? Sorry, but resource recovery is not, and never will be, 100% efficient. Or even particularly close to it, even with valuable materials. And due to the fact that the human population - and GDP per capita, which means more consumption - is ever growing, even if there was 100% efficiency you'd still need a continuous stream of new material.
How does that make even the most remote bit of sense? When did Earth become a gravityless body comprised entirely of absurdly-rich ore with no overburden which needs to export to... a different Earth?
The fact that people currently pay for these minerals attests to the fact that people find paying these sorts of prices to be "the best way to do it".
It's quite possible, of course, that technology changes might change that picture in the future. However, it's just as possible that technology changes might cause a situation where the demand for these metals goes even higher. More often than not, rare metal demands increase over time with advancing technology, not decrease.
I'm 35, female, and industrial consumption of platinum-group metals has dramatically increased since the 1960s, almost across the board.
You know, you really need to make up your mind on your insults. Am I a little kid reading comic books or am I an old geezer obsessing over obsolete resources?
Anyway, you've made your maturity level pretty clear in this thread, so it's done. Goodnight!
Even older programmers do it - I discovered just last Friday that a senior programmer I work with had written a service that was vulnerable to SQL injection (purely by accident, I was using it and noticed how it was mishandling apostrophes).
I think most programmers will do it sooner or later until either they've A) internalized the warnings from others, or B) been caught by someone noticing (and potentially exploiting) vulnerable code that they've written. And if neither A) nor B) happen immediately, they may well be serial abusers.
Also a lot of programmers seem to forget that injection doesn't just apply to SQL. Shell command insertion is also a huge abuse target.
Yes, because one just goes out and adopts - it's not like it's a multiyear process, often full of heartbreak, to get a child who more likely than not will grow up with identity issues and spend a lot of time seeing you as "not their real parent". I've been a stepmother before. It was a pretty heartbreaking experience. You know, they start crying over something and you try to console them and they start crying I want my mommy, and you reassure them that you're there for them, and they start crying, no, *MY* mommy, my *REAL* mommy.... think I really want those sort of experiences ever again? Sorry, I've just been reading some articles written from people who were adopted as children, about their attitudes toward the whole thing, and it's turning me even more off of ever considering that route.
Surrogacy is at least a bit closer. But it's illegal here. Some people pretend that they had a child overseas, but they can be investigated over it. In most cases it means spending years having to try to adopt your own child - and meanwhile having no rights over anything at all related to them.
Large mines on Earth also cost "billions upfront" - your point?
While at the same time the easiest resources become exhausted. Also, "technology gets better" often means "exploiting radically new mineral sources that were previously unavailable to you".
Right, who needs extremely hard materials that tolerate very high wear? Who needs chemicals used in fingerprint detection and electron microscopy? Who needs extreme UV reflectors? Who needs catalytic converters and industrial catalysts? Who needs flat-panel glass? Who needs mammography filters? What useless garbage.
Forget about veins - even in bulk some S-type meteorites have been measured at over 100ppm platinum-group metals, several times better than the best mine on Earth (last I checked, about 40ppm), let alone typical mines for platinum-group metals on Earth, which range from a couple hundred ppb to a few ppm. Concerning precious metals as a whole, even the *average* H-chondrite is 28ppm precious metals. L-chondrites can be up to 220 ppm precious metals. And there's no overburden - it's rich all the way through. "Veins" or other areas of unusually high concentration would just be an extra.
One could eject raw ore to Earth or concentrate it first, through any number of steps (particularly if the surface is pulverized to regolith - metallic grains can be extracted through electromagnetic processes). The key is that you should be able to eject a sintered or cast projectile on an Earth-intercept trajectory without the use of any consumables - via a coilgun. If your projectiles include sufficient metallic material to sustain an induced magnetic field than they don't need any sort of sabot. If they're shaped and sized properly you can have a stable reentry with minimal ablative burnoff and remain relatively intact after impact (too small and they'll burnup too much; too large and they'll explode too much on impact)
Our system isn't as generous as yours (Iceland), but it's still worlds beyond what America offers (no paid leave, and only rather limited unpaid leave to mothers).
I'm of mixed feelings. On one hand, I think it's a great thing to do for parents and for the kids. On the other hand, as someone who's infertile, it's kind of frustrating. I never complain to anyone in person, absolutely not. But I see all of my coworkers in their 20s and 30s having one child after the next and spending a large chunk of their time on the job... off the job.... often taking their leave in vacation homes or overseas.... I mean, I understand why the time is given, I totally sympathize... but underneath it sort of feels unfair to people who can't have children, to have such a massive benefit for those who can.
As if we haven't been extensively working on both of those things already (staying grounded on low-gravity bodies and automating robotic systems - and no, "fully automated" is not needed, there's nothing preventing the use of ground controllers on Earth).
So your conception is that one would only mine when an asteroid is near Earth? Whatever you mine and fire off may only impact earth a few years, but it doesn't change the throughput. Your returns all happen in clusters, but it's a lot of material at once.
Gold, platinum, iridium, rhodium, osmium, indium and palladium hover in the rough ballpark of $10000-60000 USD per kilogram; gem-quality peridot about the same. You don't call that "absurdly valuable"? And those prices of earth-source materials, while those wanting them for luxury purposes (as opposed to industrial purposes) would pay significant premiums for space-sourced minerals.
Of course they're all "found" on Earth. But they're all found on Earth in tiny quantities, usually upper ppb/lower ppm-levels from ore in a good mine - underneath vast amounts of overburden.
Wow, namecalling. That's surely a good way to make you totally not look like a child.
That's an overly simplistic view of asteroids. First off, we already know very well from spectroscopy that asteroids sometimes (if not usually) have varied surface material properties. Hence it seems perfectly reasonable to expect certain areas to be more or less enriched in various minerals. It's also an overly simplistic view to think of the entire body of an asteroid as being undifferentiated; asteroids have suffered being pounded by fierce impacts since the formation of our solar system, which means melt, and melt can mean differentiation - albeit localized. Lastly, there are asteroids (the largest being 16 Psyche) thought to be remnants of the cores of larger bodies. So mining them would be more like mining chunks of Earth's core - primarily nickel/iron but highly rich in heavy elements rare on Earth's surface.
We surely can see how and why. Asteroids have (generally) tiny gravitational fields. By and large, the delta-V needed to return material from an asteroid to Earth is just its earth-intercept delta-V. Which on some asteroids - earth-crossers - this energy can be tiny itself. At earth, the body can either aerocapture or go all the way in for landing. Neither of these things require an engine. There is of course the heat load to deal with. Your projectiles can be ideally shaped for reentry and with the outer layer of the hot side expected to ablate off. If you want to go straight for landing you don't have to have a parachute, there's nothing living on it. Asteroids of a certain size survive landing mostly intact (too small and they mostly burn up; too large and they mostly convert themselves to gas and plasma on impact).
Things that would be needed:
* Impact area, large enough to account for aiming errors
* Mining probe which can "hop" around the body, boil off its surface, and condense it into a ceramic or tungsten mold - OR collect loose/grind off solid material and cast it with small amounts of a binding agent or sinter it.
* Power source for the casting process: concentrated solar, high-temperature nuclear, or battery (with periodic charging and/or cable to a base station, which in turn would be solar or nuclear)
* Coil gun and system to load it, along with the power to fire it.
* Standard probe hardware: communications, cameras, compute hardware, thermal management, etc.
Reward:
* Regular shipments of absurdly valuable mineral concentrates (rare metals, gems such as olivine/peridot (if not boiled during mining - it tolerates sintering), etc). A single multitonne-tonne rock recovered on the surface may be worth in the ballpark of $1m even ignoring the (probably significant) multiplier of it having come from space (aka, would your average luxury-obsessed sultan rather have table made of gold, or a table made of Gold From Space?).
The key issue is that excepting the option of using an imported binder, all of the above options require no regular shipments of any hardware from Earth except for that required by maintenance. Meaning that once you pay your (multi-billion-dollar) capital costs (largely imposed directly or indirectly by the rocket equation), the rocket equation ceases to be relevant.
Are we ready to launch something like that today? Of course not. In space you don't just launch multi-billion dollar projects without first including test hardware on smaller probes first to try out all of the difficult aspects of what you want to do, to retire the risk. But there are no fundamental technological or economic barriers. The value of the return materials is massive and they can be launched to earth intercept with little to no consumables via electric power.
I once worked for Rockwell-Collins in the states - I started there shortly after the NASA "incident". What incident? Apparently they were caught - after doing it for many years - billing everything to the shuttle, as a matter of corporate policy. Unlike most contracts Rockwell-Collins gets, there was no cap on the Shuttle project budget. So whenever any project ran over, they just billed the engineers' time to the Shuttle. ;)
NASA does some great stuff in terms of R&D and robotic exploration. But their culture is not a good matchup for developing launch systems, whether in-house or through contractors.
Even if sand was launched to LEO, it wouldn't have a long lifespan - the smaller the object, the higher its ratio of cross section to mass. And you don't have to launch into an orbital trajectory. And if you were really bothered, rather than launching sand one could launch grains of something that would sublimate in space.
The sand itself doesn't pose a long-term debris threat. Even the act of disabling a satellite doesn't inherently do so - so long as it remains by and large a single piece. However, sand grains piercing into, say, a pressurized hydrazine tank and detonating the satellite into chunks of shrapnel of various sizes, that's a very different issue.
Which would be a relevant comment if I was talking about some sort of imaginary alternative proposal where major powers planned to fire handguns at satellites, rather than what I was actually talking about, aka giving people a sense of the energies carried by grains of sand in orbit by comparing them to the energies of bullets fired on Earth.
If two major powers (the kinds that have satellite constellations) are fighting, we have a lot more to worry about than Kessler Syndrome. Like, say, global thermonuclear annihilation.
Beam weapons are popular for their instant hit ability, but you have to have constant real-time tracking of the object (not simply a calculated trajectory), otherwise the tiniest vernier-thruster maneuver is enough to cause a miss. There's also a lot of potential countermeasures, both temporary (such as clouds of dust) and permanent (layered reflective foil skins).
If you don't need an instant hit then probably the most effective way is nothing more than a rocket full of sand. It's basically buckshot times tens of millions. If you launch opposite the direction of Earth's rotation (costs a couple thousand more m/s delta-V) you can get impact velocities in the ballpark of 15000+ m/s. A 5mg grain of sand would carry an impact force of 560 joules. By comparison, a 100mph fastball, an expert karate punch, and a professional golfer drive are all 150J. A .22LR leaves the muzzle of a gun with an energy of 168 joules, a .380 pistol with 245J, and a 9mm with 467J (again, remember that these are muzzle velocities, bullets lose energy quickly with distance). A grain of sand a satellite (aka, something that fundamentally has to be built lightweight) at 15000 m/s is just going to punch right through it. Tens of millions of them... well, you can't miss.
Also, small objects like grains of sand don't have long orbital lifespans. If you really wanted to you could fire them at a non-orbital trajectory as well. And they don't necessarily make what they hit explode, even if they punch right through it.
You joke, but there actually is a Pakistani children's show called Burqa Avenger about a burqa-wearing ninja who fights people that try to stop girls from getting an education. ;)
One could take the joke from SATW and pit an arabian or south asian woman in a burqa against a Somali ship hijacker and get an epic Ninja vs. Pirate battle ;)
Beats your usual track record.
Last I checked, non-nuclear grade had risen to around $500/kg and nuclear-grade about $1500/kg. But maybe it's changed since then, or maybe I'm remembering wrong.
Not according to the last paper I read, they did optimization work on the blanket for ITER and found that a significantly higher percentage of beryllium than lithium yields a higher breeding rate. Same paper that covered that lead-based breeding is impractical for ITER. I have to run right now but I can dig it up for you later if you want.
Not when you include enhanced geothermal. Its potential dwarfs human consumption.
Geothermal is one of those technologies that keeps slowly advancing without anyone ever seeming to take notice. It's the most underhyped cleantech of them all, in a field that normally suffers from way too much hype. Ironically it's been "dirty" energy extraction that's been helping them - the drilling technology advancements made by oil and gas companies are usually directly applicable to geothermal as well.
And some of the discoveries are accidental. Here in Iceland at the Krafla power plant they accidentally drilled into a magma chamber. Magma backed up into their well dozens of meters before stopping. Big screwup, right? Well, unlike the only other time in history this has happened (Hawaii), they decided "what the heck" and tried turning it into a production well rather than just sealing it. And it not only worked, this one well now produces half of the plant's total power generation (30 of the 60 MW). Its production temperature is 450C, which is crazy-hot for geothermal. They're now planning to do it again on purpose.
That said, it still won't be "cheap". The lithium blanket will actually contain more beryllium than lithium, which will be consumed faster than the lithium - and beryllium is something like $1500/kg. Nothing like $30k/g, but not pocket change. It's a big initial cost because you need enough of it to form the initial blanket, which is very large. It's also expensive to work with due to its toxicity (although it's relatively safe when not in a dust/vaporizeable form)
They looked at using heavy metals like lead for neutron multiplication but it just didn't work out. They have a much higher rate of neutron multiplication at high energies, but beryllium's (n, 2n) reaction extends to significantly lower energies, and that turns out to be the most important range. The thing is, you have to have neutron multiplication - if you don't then you need to capture every last fusion neutron to breed the tritium needed to produce a replacement, which obviously isn't going to happen. It's not like fission which gives off a whole shower of them, you get the one 14,1 MeV neutron and that's it.