The fact that the Troika hasn't been willing to give one iota on the Greece issue should be enough of a reflection on how little consequence they think an exit of Greece from the eurozone would be. Germany in particular doesn't want to give any ground (I imagine all of the nazi-name calling has played no small part), but they're hardly alone, many countries are taking a very hardline stance on Greece. Most parties feel that the consequence of giving way to Greece could be significant, but the consequences of their exit - while not completely painless - would not be that dramatic.
On the other hand, in Greece, there's only one route for exit, and that's capital controls (or a rapid conversion over the weekend) where everyone's assets are converted to some kind of new-drachma, which instantly devalues to half its value or less. Which is why everyone is taking their euros out of the banks, they're not stupid (unfortunately, thieves aren't stupid either, breakins have become an epidemic as they look for people hoarding money at home).
I can't see a cryptocurrency helping in any way... if anything I'd guess it'd only serve to unnerve markets even more and lose even more value as a consequence. I could picture it maybe as a simultaneous and rate-locked currency to a physical New Drachma, maybe. But it sounds IMHO like an incredibly risky move even then. I mean, one presumes for example that there's a government-controlled master key to "print" more cryptocoins? Then that means that your entire economy can be crushed overnight by someone hacking, physically stealing, misusing, cracking, or whatnot your master key. Isn't that an unnecessarily big risk to take? And on an individual level it seems full of problems as well...
Don't get me wrong, I don't think cryptocurrencies are inherently an evil or shouldn't exist. But I would have serious second thoughts about such a massive nationwide rollout on a country that's already in chaos.
Yes, aluminum is slowly becoming more adopted - although "slowly" is the operative word. Corvettes are not mass manufactured (tens of thousands per year) and are made of single-layer e-glass with polyester, which kind of sucks. Supercars are built better but are in much smaller quantities. And the point of needing to make them affordable and scaling up, that's my point.:)
You're joking, right? Before Tesla the stereotype of an electric car was a nerdy thing with the performance of a golf cart. They completely changed the public perception of electric cars, built vehicles with double the performance and range of the previous best electric cars, getting some of the highest car reviews and satisfaction ratings *ever* given for *any* type of car, and managed to start a brand new car company with a huge valuation, the first new US car company to make it big since the 1930s. Give them some F'ing credit.
Right, I cant imagine how Apple could possibly manage figuring out mass production of exotic materials...
This might allow a competitor such as apple to completely end run the industry because all those years making gas driven drive trains
You mean, like Tesla already did?
complexities in making a great steering system all vanish in this transition.
Wait, you're talking self-driving cars with *no* manual override? Okay, that's going to be permitted first thing, in the year 2047...;)
a legacy of factories not suitable for modern materials
A widespread transition to composites (which I really, really hope for) could do that, in a way that a switch to aluminum or other metals couldn't (working with aluminum isn't the same as steel, but you still have the basic principles of stamping, cutting, molding, welding etc, which all get thrown out the door when working with composites). But someone needs to find a way to make the composites competitive in a mass-manufacturing, non-niche environment. And preferably when I say "composites" we're not talking single layer E-glass and polyester here.... at the very least it needs to be foam or honeycomb cored with a vinyl ester resin to give the strength and longevity desired. Carbon fiber and epoxy would of course be even better if a good price point can be met. And hopefully in the future we'll be able to affordably get rid of more and more of those hydrogens in the structure... reinforced graphene/ta-C would probably be pretty close to the ultimate manufacturing material one could get, combining the highest known tensile strength with the highest known hardness and compressive strengths.
No, the GP is correct. The requirements for vehicles are radically different for portable electronics, and this leads to very different design choices. Tell me when was the last time you saw an iPod with an air conditioner just to cool its battery pack (which sometimes runs even when the iPod isn't in use), or a heater for cold weather charging? When was the last time you saw a iPhone with a battery that was warrantied for as much as a decade? When was the last time you saw an iPad that was rated by the manufacturer to have no problems after sitting out every day every winter in temperatures of -20C, summer temperatures of +40C with no shade, etc? When was the last time you saw any sort of portable electronics that broke its batteries up into separately sealed canisters that prevent fire from propagating from one to the next, or that can withstand a highway-speed collision? Portable electronics generally don't even do any charge balancing, let alone the sort of "be able to handle the loss of entire clusters of batteries" sort of management that vehicle packs have to be able to do (eg, rather than single cell or a couple-cells-in-series like consumer electronics, the Roadster has 6831 cells clustered into "bricks" of 69 cells in parallel to minimize the effects of individual failures, 9 bricks series per sheet, and 11 sheets, with moderate monitoring and control at the brick level and heavy monitoring and control at the sheet level).
The requirements are not similar, and as a consequence, neither are the packs.
Wrong again. Energy density is of critical importance in both applications.
No, you are the one who is again wrong. EV battery packs are generally significantly lower energy density than portable electronics battery packs, AND they generally run at lower DOD ranges, not charging up to full and not being allowed to even near total discharge. Often a lower-density chemistry is used as well for the same longevity reasons, such as a phosphate or manganese spinel (although a couple manufacturers, Tesla being the most notable, currently use cobalt 18650s). This sort of careful charge maintenance and lower density chemistry election, plus charge balancing, temperature maintenance, and fault isolation and tolerance are necessary to meet the sort of longevity demands of vehicle consumers, which are very different from the longevity demands of users of portable electronics.
The two top demands of EV battery packs are longevity and cost, and these far outstretch the importance of energy density. People could give a rat's arse if their car is 50 kilos lighter if they can't afford to purchase it or have to swap out the pack after three years. Don't get me wrong, weight is an important issue (mainly in terms of ride quality, and to a smaller degree efficiency), but it's not on the same order of magnitude of effect in terms of marketability as longevity and cost.
I think you're mixing some things up. The EV1's tires were standard size (P175/65R14) and only 50 PSI. They were low rolling resistance but nothing spectacular by modern standards. I certainly hope to see big advances in tires in the coming decades (we really need tires that can adapt to the circumstances, changing their pressure and thread area / type in contact with the ground area depending on conditions and driver demands), but there's no radical departures I'm aware of coming in the immediate future.
Yes, I would welcome any chance to see the US move to metric and catch up with everyone else.
I can't think of a single EV today that is "harder to open". But as stated I can easily envision Apple doing that. I can't envision any of the current manufacturers doing that.
It's funny to joke about, but I think the concept of them only allowing it to be serviced at Apple-certified garages would be quite high. They'd probably allow the tires and the like to be done elsewhere, but I have little doubt that they'd restrict access to any internals. And would charge a fortune for trivial tasks.
24 hours *if* you have air resistance. And then you're moving so slow that you barely get past the center.
Note that no vacuum is perfect so you will lose velocity. Their scenario should have started the person off at the south pole, not the north, for the extra altitude.
Note that the heat isn't really the materials problem that they make it out to be - it's an energy problem. You don't need a material that can withstand 4000, you just need cooling. And not linearly high cooling, but an exponential decline. The longer you cool the rock down to your target temperature, the deeper your effect on the rock temperature behind your tunnel walls, and thus the shallower the temperature gradient, and thus the lower the rate of heat loss. It's like trying to cool a hot house - the air conditioner really struggles in the beginning but it gradually becomes easier with time as the walls and everything inside the house cool down.
Now, the pressures, those are insane, and the normal approach to pressure maintenance on deep drilling - filling with a heavy mud - obviously wouldn't work here.
Sort of. Stealth aircraft are not perfect, they have some radar cross signature, and a low frequency radar significantly increases cross signatures. But the cost of this was vastly reduced range. The Serbs mentioned in the article had to wait until the plane was almost directly overhead to get a lock.
That said, that Serbian radar unit was incredibly clever, I've read about a lot of their tactics. They raided scrapyards all over the country and ripped radars off of old military jets and tweaked them to make dummies to confuse HARMs, they worked out down to seconds how long they could paint a plane before they had to flee and how to accurately predict when and where the coalition would fly what aircraft, they deliberately let jets past on bombing raids (knowing that they'd be dropping bombs on their own people) in order to get them on the way back when they'd be more vulnerable, they hand-modified their old Soviet radars to change their frequencies out of the design specs, swapping out capacitors and the like so that they wouldn't be detected by coalition forces and would stand a better chance at hitting stealth craft, etc. They were drilled and managed incredibly well. If the whole Serbian military had done as well as they did, Serbia would have held out far better.
It's a cute concept, but the simple fact is, if you have some simple technology for gravity control that can take a primitive society whizzing around the cosmos, then that primitive society wouldn't be using flintlocks for battle. Because if you control gravity to the point that you can hop some primitive ship in and out of gravity wells and move at relativistic speeds then you're controlling *vast* amounts of energy to do so. And there's no way such a species is going to only make use of this vast amount of energy in their spaceships but not their weapons - even if they're only kinetic impactors.
My thoughts exactly. The environments we've physically checked so far are:
Earth: High degree of confidence that there is life here. Moon: A couple spots on the surface, moderate degree of confidence that there is no life there. Surface in general, low degree of confidence, based only on comparing the few places we've checked with how the geology looks from orbit, with no data from many types of terrain. Elsewhere: no degree of confidence. Mars: Same. Elsewhere in the solar system: no degree of confidence (no other probes to other bodies have returned samples or returned data that would allow us to have any sort of confidence in determining whether life was present or not) Elsewhere in the universe: no degree of confidence.
Many people gladly make assumptions about where life would or wouldn't be, but that's of course highly anthropocentric. "We need water, a solid rocky surface, a low radiation environment, temperatures in the 273-330 kelvin range, and these building blocks..." - you have no idea what you actually need, you have a sample size of "1". That's why people obsess over, say, Europa, despite us having absolutely zero evidence that there's any sort of life there. Heck, the best direct evidence currently on hand for life outside of Earth is probably Titan's "acetylene / ethane, hydrogen, and methane problem" (acetylene and ethane seem to be highly deficient at the surface compared to what should be there; there's some evidence that hydrogen may be disappearing at the surface; and Titan's methane persistence over geological times has long baffled; before the data on acetylene, ethane, and hydrogen was even known, it had been theorized that any life on Titan would most likely metabolize acetylene and ethane with hydrogen into methane). Plus, we know that there's extensive organic chemistry making all kinds of complex CHN "building blocks" in the upper atmosphere. But any life on Titan would have to be utterly different than LAWKI to survive the radically different environment.
The better analogy would be near-earth objects. Even still, they stay in (sort of) fixed orbits, generally close to the orbital plane of the planets, and don't try to avoid detection. Yet we're nonetheless pretty terrible at detecting "ship-sized" NEOs. If by "ship-sized" one means "aircraft carrier-sized", odds are better than not that it wouldn't be spotted until it was within the orbit of the moon. If we're talking "space shuttle sized", it probably wouldn't be spotted until it got near LEO.
It wouldn't be so much of a problem if the US definition of "allies" wasn't so lax (Israel, Colombia, Bahrain, etc). Don't get me wrong - I'd pick the US over Russia for example any day. But that doesn't mean that I'm comfortable with all of the US's "allies" having the right to buy the US's latest weapons, on their word alone.
Interesting story behind that... Theodore Gray was one of the cofounders of Wolfram Research with Stephen Wolfram. Apparently long ago there was a brewing trademark battle with another company over the Wolfram name. He resolved it by convincing the other company to go with Tellurium for their name (without mentioning that tellurium is a toxic metal that gives people exposed to it nasty, chronic BO)
What sort of concentration of ethephon should I spray on my papayuela (V. pubescens) to induce female flowering? I have two plants but they're both male and I've heard that it can be effective, but ran into no information about the concentrations required. And should I be spraying just the flowers, or the whole plant?
It should also be added that one should expect any life on vastly different planets to be vastly different to life on Earth, just because the environments are so different; trying to shoehorn Earth life into an alien environment is a poor fit. Martian surface life would need to be highly peroxide, radiation, and cold tolerant. I remember when people were worrying about microbes contaminating Titan with the Huygens probe - as if Earth microbes would suddenly adapt to an environment with no oxygen or CO2 and temperatures cold enough to liquify methane. Any life on Titan would have to have a chemistry totally unlike that on Earth to survive the cold, and would need to metabolize ethane, acetylene, and other hydrocarbons with hydrogen to produce methane - a metabolic cycle not found on Earth (curiously, there is some very interesting evidence that that might actually be happening on Titan... but that is neither here nor there)
Thankfully for Mars, it has excellent sterilization of its own. And not just the heat of aerocapture; the regolith is full of peroxides.
I really don't think Earth life could spread on Mars just from a couple of poorly sterilized probes. Perhaps given enough generations life could adapt to Martian environment, but there's not going to be any "generations" when there's no suitable environment for reproduction to begin with. It's like dropping a few bacteria into a container of bleach and expecting them to just evolve into bleach-eaters on the spot.
I don't deny that at all. Peak oil would actually be great for the climate. Unfortunately, no magical supply peak is going to save the climate from us.
EROEI is only relevant when looked at as an entire system perspective.
The Luftwaffe in the latter part of WWII was largely fuelled with aviation fuel made from coal. The primitive coal to liquids technology they used was very inefficient tech consuming way more energy of coal than it produced jet fuel (highly negative EROEI). Yet it kept the Germans in the air until the plants were bombed.
How can that possibly be? How could a negative EROEI work? Simple: because the net energy picture was still positive. Energy from coal in, less energy from jet fuel out. And the economic picture worked because you can't stick coal in a jet's fuel tank and fly it.
Oil doesn't have to be some super high EROEI fuel to work. It doesn't even have to be a positive EROEI fuel to work. So long as you can put it in your gas tank, and so long as the world can produce energy to make it, it can get alone just fine.
Even as it stands, oil is already a fuel whose value is many times higher than its raw energy value. Compare the per-BTU costs of coal or natural gas to that of oil - even in our current low oil price regime. Oil's value isn't it's energy value. It's the ability to drive an engine with it that makes it valuable. Changing other forms of energy into oil is a perfectly realistic economic proposition.
That said, in reality, oil is far, far from a negative EROEI, and won't be going negative for a long, long time, if ever - not that that matters.
It would be great if you could find someone who would pledge to pay your legal bills if the FAA sues you, and then launch anyway and hopefully use it to save someone's life. The publicity such a case would bring would do wonders for improving drone regulations.
Yeah, and you should get money for every satellite that passes over you too!
First off, nobody is talking about flying "a few feet over your house". Unless you just ordered something, wherein one would presume that you're giving the drone permission to come to your house.
Secondly, you purchased a piece of ground. Not a cylinder of area reaching from the Earth's core up to the edge of the known universe. You have rights in the immediate vicinity of your house, but not far above it. As it should be.
A drone (or anything that is designed to fly) is supported in the air by the air going over it's airfoils.
The amazon drones are quadcopters. They have no airfoils other than the propellers (rapidly rotating airfoils, moving at speeds faster than even tornado-force winds).
A tree branch, barring some insignificant wind resistance
Last I checked, tree branches breaking and falling into houses during windstorms is not a myth, so I'm not sure what exactly you're going on about.
No matter it's horizontal or rotational velocity, if unsupported, it will accelerate to terminal velocity straight down
You'll find that the terminal velocity of a branch is far higher than the terminal velocity of a quadcopter. Even completely unpowered, propellers undergo autorotation when falling, which acts as a brake.
However, the air around it is not still, it can move in any direction. And the drone will move with the air, even a slight breeze, since the air is the only thing supporting it. An airplane flying at 50 MPH airspeed in a 60 MPH headwind will be traveling over the ground backwards at 10 MPH.
Meanwhile, windblown debris will be moving at up to 60 MPH with 36 times the kinetic energy per kilogram.
And seriously, are you so daft as to think that Amazon and others would be licensed to launch drones in a hurricane? Launches would very obviously be limited to times where the peak anticipated gust speed is still with a large margin of error controllable by the craft; it's absurd to think licensing would allow anything else.
It does not take much wind to blow a drone off course
Actually, drones that lock to GPS positions are incredibly hard to blow significantly off course (look at how little the drone has to rotate off the vertical to hold position - it could easily tolerate winds far stronger than that). You clearly know nothing about drones if you think they're easy to blow off course. If they have to use their whole power output to hold position, they do just that.
go watch small aircraft take off and land at an airport in a 10+ MPH gusting wind
Quadcopers are not light planes. You might as well start comparing quadcopters to eagles next. "Look, Amazon's drones are going to steal all of our salmon! Look at what eagles do!"
and they are 20 times as heavy
With many hundreds of times the surface area, with no ability for rapid changes in angle or power output, and no computer control system to do so automatically.
with a much more powerful engine than any drone.
Power to weight ratios on drones are many times higher than on light planes. Which is obviously what matters, and I certainly hope you're not daft enough to think that absolute power is what matters.
It takes far, far, far less wind to blow one off course than a falling tree branch
Do I really need to reiterate my entire previous post?
A 10 MPH gust can happen without being forecast and will absolutely toss a drone
Yes, about 10 centimeters before the control software compensates.
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The fact that the Troika hasn't been willing to give one iota on the Greece issue should be enough of a reflection on how little consequence they think an exit of Greece from the eurozone would be. Germany in particular doesn't want to give any ground (I imagine all of the nazi-name calling has played no small part), but they're hardly alone, many countries are taking a very hardline stance on Greece. Most parties feel that the consequence of giving way to Greece could be significant, but the consequences of their exit - while not completely painless - would not be that dramatic.
On the other hand, in Greece, there's only one route for exit, and that's capital controls (or a rapid conversion over the weekend) where everyone's assets are converted to some kind of new-drachma, which instantly devalues to half its value or less. Which is why everyone is taking their euros out of the banks, they're not stupid (unfortunately, thieves aren't stupid either, breakins have become an epidemic as they look for people hoarding money at home).
I can't see a cryptocurrency helping in any way... if anything I'd guess it'd only serve to unnerve markets even more and lose even more value as a consequence. I could picture it maybe as a simultaneous and rate-locked currency to a physical New Drachma, maybe. But it sounds IMHO like an incredibly risky move even then. I mean, one presumes for example that there's a government-controlled master key to "print" more cryptocoins? Then that means that your entire economy can be crushed overnight by someone hacking, physically stealing, misusing, cracking, or whatnot your master key. Isn't that an unnecessarily big risk to take? And on an individual level it seems full of problems as well...
Don't get me wrong, I don't think cryptocurrencies are inherently an evil or shouldn't exist. But I would have serious second thoughts about such a massive nationwide rollout on a country that's already in chaos.
Yes, aluminum is slowly becoming more adopted - although "slowly" is the operative word. Corvettes are not mass manufactured (tens of thousands per year) and are made of single-layer e-glass with polyester, which kind of sucks. Supercars are built better but are in much smaller quantities. And the point of needing to make them affordable and scaling up, that's my point. :)
You're joking, right? Before Tesla the stereotype of an electric car was a nerdy thing with the performance of a golf cart. They completely changed the public perception of electric cars, built vehicles with double the performance and range of the previous best electric cars, getting some of the highest car reviews and satisfaction ratings *ever* given for *any* type of car, and managed to start a brand new car company with a huge valuation, the first new US car company to make it big since the 1930s. Give them some F'ing credit.
Because that's clearly their field of expertise?
You mean, like Tesla already did?
Wait, you're talking self-driving cars with *no* manual override? Okay, that's going to be permitted first thing, in the year 2047... ;)
A widespread transition to composites (which I really, really hope for) could do that, in a way that a switch to aluminum or other metals couldn't (working with aluminum isn't the same as steel, but you still have the basic principles of stamping, cutting, molding, welding etc, which all get thrown out the door when working with composites). But someone needs to find a way to make the composites competitive in a mass-manufacturing, non-niche environment. And preferably when I say "composites" we're not talking single layer E-glass and polyester here.... at the very least it needs to be foam or honeycomb cored with a vinyl ester resin to give the strength and longevity desired. Carbon fiber and epoxy would of course be even better if a good price point can be met. And hopefully in the future we'll be able to affordably get rid of more and more of those hydrogens in the structure... reinforced graphene/ta-C would probably be pretty close to the ultimate manufacturing material one could get, combining the highest known tensile strength with the highest known hardness and compressive strengths.
No, the GP is correct. The requirements for vehicles are radically different for portable electronics, and this leads to very different design choices. Tell me when was the last time you saw an iPod with an air conditioner just to cool its battery pack (which sometimes runs even when the iPod isn't in use), or a heater for cold weather charging? When was the last time you saw a iPhone with a battery that was warrantied for as much as a decade? When was the last time you saw an iPad that was rated by the manufacturer to have no problems after sitting out every day every winter in temperatures of -20C, summer temperatures of +40C with no shade, etc? When was the last time you saw any sort of portable electronics that broke its batteries up into separately sealed canisters that prevent fire from propagating from one to the next, or that can withstand a highway-speed collision? Portable electronics generally don't even do any charge balancing, let alone the sort of "be able to handle the loss of entire clusters of batteries" sort of management that vehicle packs have to be able to do (eg, rather than single cell or a couple-cells-in-series like consumer electronics, the Roadster has 6831 cells clustered into "bricks" of 69 cells in parallel to minimize the effects of individual failures, 9 bricks series per sheet, and 11 sheets, with moderate monitoring and control at the brick level and heavy monitoring and control at the sheet level).
The requirements are not similar, and as a consequence, neither are the packs.
No, you are the one who is again wrong. EV battery packs are generally significantly lower energy density than portable electronics battery packs, AND they generally run at lower DOD ranges, not charging up to full and not being allowed to even near total discharge. Often a lower-density chemistry is used as well for the same longevity reasons, such as a phosphate or manganese spinel (although a couple manufacturers, Tesla being the most notable, currently use cobalt 18650s). This sort of careful charge maintenance and lower density chemistry election, plus charge balancing, temperature maintenance, and fault isolation and tolerance are necessary to meet the sort of longevity demands of vehicle consumers, which are very different from the longevity demands of users of portable electronics.
The two top demands of EV battery packs are longevity and cost, and these far outstretch the importance of energy density. People could give a rat's arse if their car is 50 kilos lighter if they can't afford to purchase it or have to swap out the pack after three years. Don't get me wrong, weight is an important issue (mainly in terms of ride quality, and to a smaller degree efficiency), but it's not on the same order of magnitude of effect in terms of marketability as longevity and cost.
I think you're mixing some things up. The EV1's tires were standard size (P175/65R14) and only 50 PSI. They were low rolling resistance but nothing spectacular by modern standards. I certainly hope to see big advances in tires in the coming decades (we really need tires that can adapt to the circumstances, changing their pressure and thread area / type in contact with the ground area depending on conditions and driver demands), but there's no radical departures I'm aware of coming in the immediate future.
Yes, I would welcome any chance to see the US move to metric and catch up with everyone else.
I can't think of a single EV today that is "harder to open". But as stated I can easily envision Apple doing that. I can't envision any of the current manufacturers doing that.
It's funny to joke about, but I think the concept of them only allowing it to be serviced at Apple-certified garages would be quite high. They'd probably allow the tires and the like to be done elsewhere, but I have little doubt that they'd restrict access to any internals. And would charge a fortune for trivial tasks.
24 hours *if* you have air resistance. And then you're moving so slow that you barely get past the center.
Note that no vacuum is perfect so you will lose velocity. Their scenario should have started the person off at the south pole, not the north, for the extra altitude.
Note that the heat isn't really the materials problem that they make it out to be - it's an energy problem. You don't need a material that can withstand 4000, you just need cooling. And not linearly high cooling, but an exponential decline. The longer you cool the rock down to your target temperature, the deeper your effect on the rock temperature behind your tunnel walls, and thus the shallower the temperature gradient, and thus the lower the rate of heat loss. It's like trying to cool a hot house - the air conditioner really struggles in the beginning but it gradually becomes easier with time as the walls and everything inside the house cool down.
Now, the pressures, those are insane, and the normal approach to pressure maintenance on deep drilling - filling with a heavy mud - obviously wouldn't work here.
Sort of. Stealth aircraft are not perfect, they have some radar cross signature, and a low frequency radar significantly increases cross signatures. But the cost of this was vastly reduced range. The Serbs mentioned in the article had to wait until the plane was almost directly overhead to get a lock.
That said, that Serbian radar unit was incredibly clever, I've read about a lot of their tactics. They raided scrapyards all over the country and ripped radars off of old military jets and tweaked them to make dummies to confuse HARMs, they worked out down to seconds how long they could paint a plane before they had to flee and how to accurately predict when and where the coalition would fly what aircraft, they deliberately let jets past on bombing raids (knowing that they'd be dropping bombs on their own people) in order to get them on the way back when they'd be more vulnerable, they hand-modified their old Soviet radars to change their frequencies out of the design specs, swapping out capacitors and the like so that they wouldn't be detected by coalition forces and would stand a better chance at hitting stealth craft, etc. They were drilled and managed incredibly well. If the whole Serbian military had done as well as they did, Serbia would have held out far better.
It's a cute concept, but the simple fact is, if you have some simple technology for gravity control that can take a primitive society whizzing around the cosmos, then that primitive society wouldn't be using flintlocks for battle. Because if you control gravity to the point that you can hop some primitive ship in and out of gravity wells and move at relativistic speeds then you're controlling *vast* amounts of energy to do so. And there's no way such a species is going to only make use of this vast amount of energy in their spaceships but not their weapons - even if they're only kinetic impactors.
My thoughts exactly. The environments we've physically checked so far are:
Earth: High degree of confidence that there is life here.
Moon: A couple spots on the surface, moderate degree of confidence that there is no life there. Surface in general, low degree of confidence, based only on comparing the few places we've checked with how the geology looks from orbit, with no data from many types of terrain. Elsewhere: no degree of confidence.
Mars: Same.
Elsewhere in the solar system: no degree of confidence (no other probes to other bodies have returned samples or returned data that would allow us to have any sort of confidence in determining whether life was present or not)
Elsewhere in the universe: no degree of confidence.
Many people gladly make assumptions about where life would or wouldn't be, but that's of course highly anthropocentric. "We need water, a solid rocky surface, a low radiation environment, temperatures in the 273-330 kelvin range, and these building blocks..." - you have no idea what you actually need, you have a sample size of "1". That's why people obsess over, say, Europa, despite us having absolutely zero evidence that there's any sort of life there. Heck, the best direct evidence currently on hand for life outside of Earth is probably Titan's "acetylene / ethane, hydrogen, and methane problem" (acetylene and ethane seem to be highly deficient at the surface compared to what should be there; there's some evidence that hydrogen may be disappearing at the surface; and Titan's methane persistence over geological times has long baffled; before the data on acetylene, ethane, and hydrogen was even known, it had been theorized that any life on Titan would most likely metabolize acetylene and ethane with hydrogen into methane). Plus, we know that there's extensive organic chemistry making all kinds of complex CHN "building blocks" in the upper atmosphere. But any life on Titan would have to be utterly different than LAWKI to survive the radically different environment.
The better analogy would be near-earth objects. Even still, they stay in (sort of) fixed orbits, generally close to the orbital plane of the planets, and don't try to avoid detection. Yet we're nonetheless pretty terrible at detecting "ship-sized" NEOs. If by "ship-sized" one means "aircraft carrier-sized", odds are better than not that it wouldn't be spotted until it was within the orbit of the moon. If we're talking "space shuttle sized", it probably wouldn't be spotted until it got near LEO.
Huge fireworks that spray out candy at high velocity and are lethal within a 5-meter radius?
It wouldn't be so much of a problem if the US definition of "allies" wasn't so lax (Israel, Colombia, Bahrain, etc). Don't get me wrong - I'd pick the US over Russia for example any day. But that doesn't mean that I'm comfortable with all of the US's "allies" having the right to buy the US's latest weapons, on their word alone.
Interesting story behind that... Theodore Gray was one of the cofounders of Wolfram Research with Stephen Wolfram. Apparently long ago there was a brewing trademark battle with another company over the Wolfram name. He resolved it by convincing the other company to go with Tellurium for their name (without mentioning that tellurium is a toxic metal that gives people exposed to it nasty, chronic BO)
What sort of concentration of ethephon should I spray on my papayuela (V. pubescens) to induce female flowering? I have two plants but they're both male and I've heard that it can be effective, but ran into no information about the concentrations required. And should I be spraying just the flowers, or the whole plant?
It should also be added that one should expect any life on vastly different planets to be vastly different to life on Earth, just because the environments are so different; trying to shoehorn Earth life into an alien environment is a poor fit. Martian surface life would need to be highly peroxide, radiation, and cold tolerant. I remember when people were worrying about microbes contaminating Titan with the Huygens probe - as if Earth microbes would suddenly adapt to an environment with no oxygen or CO2 and temperatures cold enough to liquify methane. Any life on Titan would have to have a chemistry totally unlike that on Earth to survive the cold, and would need to metabolize ethane, acetylene, and other hydrocarbons with hydrogen to produce methane - a metabolic cycle not found on Earth (curiously, there is some very interesting evidence that that might actually be happening on Titan... but that is neither here nor there)
Thankfully for Mars, it has excellent sterilization of its own. And not just the heat of aerocapture; the regolith is full of peroxides.
I really don't think Earth life could spread on Mars just from a couple of poorly sterilized probes. Perhaps given enough generations life could adapt to Martian environment, but there's not going to be any "generations" when there's no suitable environment for reproduction to begin with. It's like dropping a few bacteria into a container of bleach and expecting them to just evolve into bleach-eaters on the spot.
Yeah, well I'm a scientician, and I say the evidence suggests a martian supereruption!
You're supposed to include a picture every time you mention him ;)
I don't deny that at all. Peak oil would actually be great for the climate. Unfortunately, no magical supply peak is going to save the climate from us.
EROEI is only relevant when looked at as an entire system perspective.
The Luftwaffe in the latter part of WWII was largely fuelled with aviation fuel made from coal. The primitive coal to liquids technology they used was very inefficient tech consuming way more energy of coal than it produced jet fuel (highly negative EROEI). Yet it kept the Germans in the air until the plants were bombed.
How can that possibly be? How could a negative EROEI work? Simple: because the net energy picture was still positive. Energy from coal in, less energy from jet fuel out. And the economic picture worked because you can't stick coal in a jet's fuel tank and fly it.
Oil doesn't have to be some super high EROEI fuel to work. It doesn't even have to be a positive EROEI fuel to work. So long as you can put it in your gas tank, and so long as the world can produce energy to make it, it can get alone just fine.
Even as it stands, oil is already a fuel whose value is many times higher than its raw energy value. Compare the per-BTU costs of coal or natural gas to that of oil - even in our current low oil price regime. Oil's value isn't it's energy value. It's the ability to drive an engine with it that makes it valuable. Changing other forms of energy into oil is a perfectly realistic economic proposition.
That said, in reality, oil is far, far from a negative EROEI, and won't be going negative for a long, long time, if ever - not that that matters.
It would be great if you could find someone who would pledge to pay your legal bills if the FAA sues you, and then launch anyway and hopefully use it to save someone's life. The publicity such a case would bring would do wonders for improving drone regulations.
Yeah, and you should get money for every satellite that passes over you too!
First off, nobody is talking about flying "a few feet over your house". Unless you just ordered something, wherein one would presume that you're giving the drone permission to come to your house.
Secondly, you purchased a piece of ground. Not a cylinder of area reaching from the Earth's core up to the edge of the known universe. You have rights in the immediate vicinity of your house, but not far above it. As it should be.
The amazon drones are quadcopters. They have no airfoils other than the propellers (rapidly rotating airfoils, moving at speeds faster than even tornado-force winds).
Last I checked, tree branches breaking and falling into houses during windstorms is not a myth, so I'm not sure what exactly you're going on about.
You'll find that the terminal velocity of a branch is far higher than the terminal velocity of a quadcopter. Even completely unpowered, propellers undergo autorotation when falling, which acts as a brake.
Meanwhile, windblown debris will be moving at up to 60 MPH with 36 times the kinetic energy per kilogram.
And seriously, are you so daft as to think that Amazon and others would be licensed to launch drones in a hurricane? Launches would very obviously be limited to times where the peak anticipated gust speed is still with a large margin of error controllable by the craft; it's absurd to think licensing would allow anything else.
Actually, drones that lock to GPS positions are incredibly hard to blow significantly off course (look at how little the drone has to rotate off the vertical to hold position - it could easily tolerate winds far stronger than that). You clearly know nothing about drones if you think they're easy to blow off course. If they have to use their whole power output to hold position, they do just that.
Quadcopers are not light planes. You might as well start comparing quadcopters to eagles next. "Look, Amazon's drones are going to steal all of our salmon! Look at what eagles do!"
With many hundreds of times the surface area, with no ability for rapid changes in angle or power output, and no computer control system to do so automatically.
Power to weight ratios on drones are many times higher than on light planes. Which is obviously what matters, and I certainly hope you're not daft enough to think that absolute power is what matters.
Do I really need to reiterate my entire previous post?
Yes, about 10 centimeters before the control software compensates.