I wouldn't say that temperature is the least of the problems - temperature isn't a problem for O-ring seals either, but try telling that to the crew of whats-that-shuttle's-name.
But handling gases (under containment) is one set of issues, and handling flammable gasses is another set of issues.
There are likely to be "learning experiences", but since the space is hardly unexplorerd... I wouldn't be overly worried about it. From a distance.
Most marijuana farms round here (which need to be indoors, it doesn't grow well out of doors here) just short-circuit the meter. It's not as if they're going to be around for long after all.
Moderate cryogenic storage of liquified hydrocarbons is a well-known industrial technique. You can get pressurised propane/ butane mix at any camping store. Pure propane is moderately more difficult. Ethane - shouldn't be a problem. I'm trying to remember if methane is higher or lower boiling point than nitrogen... Methane 112K, nitrogen 72K ; that's good.
I see tankers of liquid nitrogen on the road all the time round here, so the temperatures aren't a problem. And you could purge the headspace above the methane with nitrogen to avoid fire worries.
I don't see any show stoppers. If it's needed, it could be done, and no major new technologies need developing.
If the Fukushima reactor can melt its way through a concrete floor,
Huh?
Checks the IAEA status page. No mention of reactors melting their way through concrete floors there.
Your source is?
Getting back to Europa... if you hand-wave a large power supply onto Europa's surface then you have got round many problems, but not all.
another one in orbit around Europa. The latter might an earlier reconnaissance probe that's repurposed for that end.
Saturn's system is crowded - 60-odd moons known. How stable will an orbit around Europa be? Serious question.
Your previous, re-purposed probe presumably has it's own power supply, which will almost certainly be solar panels. Their lifetime? Their power output? Fuel for station-keeping and orbit correction?
It's not so simple. I would like it if it were that simple, but it's not.
They volunteered ; why should they expect additional protection?
(And FYI I have a close relative who has recently been stupid enough to sign up and is currently in Afghanistan getting shot at. None of which changes the fact that he's been a bloody idiot and that he may die for it. And as an adult he's chosen to do something dangerous and unproductive, which is his choice. I'd understand it better if he was doing something fun like driving excessively fast or parachuting (for fun, not for pay), but it's his choice. I'm not obliged to support him though.)
I keep on hearing people mentioning Visio as if it's something important. Never seen it or heard of it at work... what does it do? Ah, it's a vector graphics programme. OK, that makes it a Class 3 problem : not a small problem, or a big problem, but someone else's problem.
Actually, technically it probably is to a degree my problem - a major part of my work is in producing what are essentially special purpose vector drawings, fed off a large database. But again, since work supplies the software for me (or if a client wants to use something else, they provide it, a dongle, and a manual), that's not a problem.
That's not an interesting problem (to me). But you do need to be able to predict earthquakes with considerable accuracy to be able to say whether your intervention (whatever that intervention is) has had any significant effect.
OK, I suspect that you were making a joke. I'm not.
Oh, and by the way ; if I were to expend significant effort on thinking of methods of earthquake prediction or of prevention (or less unlikely, reduction in intensity), I'd concentrate on the important areas for preventing death and suffering - the Ganges valley and Himalayan foredeep - where confidently predictable death tolls from the confidently predictable "big one" are in the tens of millions. Or more. For your information, such a quake appears to be decades if not a century overdue, judging from the historical record.
In space you have unlimited free energy from the sun.
It's not unlimited, and it's not free. The intensity of sunlight at any particular position in the solar system is more or less constant but finite. So you can increase the power available to you by increasing the area of your collector, until you have a Dyson Sphere. BUT, the weight you have to put into orbit (more precisely, "into this particular orbit") will increase more-or-less linearly with the area of the collector. And putting weight into orbit is not free.
Let's not even get into the fact that solar cells do degrade with time.
The solar energy available may be considerable, and the per-unit cost low, but it's not unlimited and it's not free.
Place a satellite in high orbit and have it use a laser to push debris down into the atmosphere where it can burn up. Aim it so that if you miss the beam goes off into space rather than towards the ground.
You'd need to put your beam weapon into an orbit at similar altitude to the debris you're aiming at. Otherwise, the Earth is going to form a backdrop to your beam. OK, maybe you'll be lucky and only burn out the eyes of a third-world farmer instead of the remaining pilot of Queen Kathrine's plane. But maybe it's better to not take that risk?
I'd put my beam weapon in a relatively low orbit, and fire upwards at debris as it approaches it's apogee (highest orbital point w.r.t. Earth) reducing it's kinetic energy and so lowering it's perigee (lowest orbital point) and making it's orbit more eccentric; it will then lose more energy each time it goes lower... until it eventually burns up. You might need to make several applications of the beam to control it's fall location - the south Pacific is popular.
No more debris in the appropriate orbital regions? Use your power supply and some trailing cables to pul your beam weapon into a different orbit by acting on the magnetic field. Lather, rinse, repeat.
Whether it would work sufficiently economically? I don't know. Is it impossible? I think not.
In my book, people who do not have a solution for a problem can hardly be considered experts in the problem.
Your definition may cause you no problems when communicating with yourself. However since the general purpose of communication is to communicate with others, then it becomes necessary to stick reasonably closely to what other people mean by words. Consult Tweedledum and Tweedledee for further discussion (not debate).
An example : I am a geologist, and I pay some fair amount of attention to seismology because it's interesting, and understanding how energy moves through the Earth is a (minor) part of my day-to-day work. Compared to 99.9% of the population, that makes me very well informed on seismology and earthquake studies ; I could make a fair case for being considered an expert.
I do not have, and do not know of any credible expert (by my definition) seismologist who claims to have, any solution to the problem of predicting if there is going to be an earthquake of more then magnitude X in geographical region Y in future time period Z.
By your standards, there are no experts in seismology.
Do you know of any credible experts in interstellar travel? Or faster-than-light travel?
Your book is your book. But other people use different books.
Never used any of them (one is an IM product? I've had to use IM sometimes at work, but I simply don't see the point.).
Do you find any problems with using these when you're outside the US? I'm assuming that you have a US-location set up on your systems so that most of the sign-up issues are not valid. And when I go to work in Norway next week, I'll be in the US as far as the Internet is concerned.
Basically, once skype is carefully accidentally closed to all but win7, and MS is the monopoly provider of win7, skype will be tied to it.
And I'll then be demanding refund of the unused part of my subscription, as well as some explanation of how I'm going to use my advertised online number now that they've shut down access to it.
Of course, if they continue making it accessible through Linux, no real problem. I'll still distrust M$, but if they don't slam the door on this product, then I'm not rabid enough to leave on that basis.
Will be interesting to see what actually happens. And I'd better start to investigate alternatives.
Hexane isn't an aromatic. "Aromatic", in the context of chemistry not perfumery, means that the compound contains rings of carbon atoms with alternating single and double bonds, which bonds hybridise to produce electron clouds that are not localised between(/around) a particular pair of atoms.
Cyclohexane is a cyclic hydrocarbon with a different formula to hexane (C6H12, versus C6H14). Cyclohexane isn't aromatic either.
CyclohexEne (note emphasis) is an unsaturated cyclic hydrocarbon, formula C6H10. It isn't aromatic either.
Cyclohex-di-ene describes two closely related unsaturated cyclic hydrocarbons, each with two non-adjacent double carbon-carbon bonds, formulae C6H8. One form will have some delocalisation of the electron quadruple, but whether that makes it aromatic could probably occupy a degree-level exam answer.
Cyclohex-tri-ene is an unsaturated cyclic hydrocarbon with full delocalisation of all the bonding electrons around the ring. It's better known as benzene.
I take appropriate care to reduce my exposure to benzene. It's a well-established carcinogen.
Cyclohex-di-ene I don't recall ever having met (and I do read and understand product labels ; dad was a chemist, you learn to do these things young).
I've had extensive skin burns from linear hexadec-1-ene (under it's one of it's trade names, "UltiDrill"), so I'd be pretty wary of coming into contact with any linear unsaturated hydrocarbons, and by implication, I'd be careful of coming into contact with any such. (Not paranoid, but careful. Pass the gloves from my bag ; they're next to the polythene apron.)
Cyclohexane and hexane I've no particular concerns about (apart from them being volatile, and flammable).
I've never seen any notion of the Milky Way in the sky... how clear is it in an unpolluted area?
I don't know, I've never seen an unpolluted area.
(I have worked on 4 continents, up to several hundreds of miles from the nearest street light, which might qualify as "less polluted" areas, but not "unpolluted" by any means.)
Well, OK, then the Allies are "winners for now" against the Axis powers in World War Two.
Happy?
Did you read your ballot papers for last week's election? Mine had three - count them, three - different variants on the resurgent Nazi Party.
Come back in a century and you might well see that the Nazis are back in power and regretting their temporary setback in the second half of the twentieth century.
The angular momentum of a Niven Ring is going to be LOTS, so to apply sufficient torque to get it to precess is also going to require LOTS of torque. Which means lots of mass - for a gravitational torque.
So, unless the inhabitants are deliberately precessing it - to signal? - using the attitude jet system, it's going to be very stable. So if we're seeing the star today, we'll be seeing it tomorrow and on into the future, unless the normal processes of galactic circulation takes us into the part of space occulted by the Ring (as seen from the star), we're unlikely to see any significant change.
Actually, this is inherent in the stories (and I've enough confidence in Larry Niven to have done his homework, or at least to have had his numbers checked since the embarrassment of that song to expect him to be right on this) : the Pak built the RingWorld (sorry, am I spoiling things for people who haven't read the whole series?) for protection against the Core Explosion. So they expected it to stay properly oriented w.r.t. the Core over inhumanly-long time scales.
There is a minor caveat : the shadows of the Shadow Squares will overlap the edges of the Ring significantly - otherwise there would be parts of the Ring without a day-night cycle. Therefore there would be two narrow regions with the on-off signal of the Shadow Squares. Which would be interesting, particularly since the Shadow Squares can have their spacing changed from the Repair Centre. That would provide a very difficult-to-interpret signal.
I wasn't terribly surprised by being shut down ; I wasn't expecting the grounds to be "hosting too many multimedia files on my site" when they were all password-protected and they shouldn't have been able to see what the contents of the zips were.
I was expecting to find out what their real limits were and then negotiate an appropriate rate, or trim my storage to an appropriate size. I didn't expect an immediate uncompromising shut-down.
So, off to Flickr for a paid account, and upload all the photos there. $25/year for unlimited, they say, and I know I'm nowhere near their limits.
Coincidentally, I was just driving past the Scottish home of Thomas Glover, "the Scottish Samurai", who was an engineer and merchant involved in the start-up of what eventually became Mitsubishi Corporation. He was responsible for the import of Japan's first locomotive, and thus indirectly for the choice of the commonest gauge of line in the country.
Do you mean "most jurisdictions", or do you mean "in the jurisdiction which I'm most familiar with"?
Can you back up "most jurisdictions" with some numbers? I wouldn't even be sure of it being a majority for "any" data. I know for sure that certain personal medical information the doctors here are obliged to report to the relevant authorities.
I also remember cases such as the infamous "Typhoid Mary" that suggests that the situation in your locality may not be exactly as you paint it ; sometimes limits to personal liberty are perfectly reasonable.
[None of which considers the difference between what the law says should happen and what actually does happen ; different question.]
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But handling gases (under containment) is one set of issues, and handling flammable gasses is another set of issues.
There are likely to be "learning experiences", but since the space is hardly unexplorerd ... I wouldn't be overly worried about it. From a distance.
Most marijuana farms round here (which need to be indoors, it doesn't grow well out of doors here) just short-circuit the meter. It's not as if they're going to be around for long after all.
Only because they'd not developed antifreeze.
Moderate cryogenic storage of liquified hydrocarbons is a well-known industrial technique. You can get pressurised propane/ butane mix at any camping store. Pure propane is moderately more difficult. Ethane - shouldn't be a problem. I'm trying to remember if methane is higher or lower boiling point than nitrogen ... Methane 112K, nitrogen 72K ; that's good.
I see tankers of liquid nitrogen on the road all the time round here, so the temperatures aren't a problem. And you could purge the headspace above the methane with nitrogen to avoid fire worries.
I don't see any show stoppers. If it's needed, it could be done, and no major new technologies need developing.
Huh?
Checks the IAEA status page. No mention of reactors melting their way through concrete floors there.
Your source is?
Getting back to Europa ... if you hand-wave a large power supply onto Europa's surface then you have got round many problems, but not all.
Saturn's system is crowded - 60-odd moons known. How stable will an orbit around Europa be? Serious question.
Your previous, re-purposed probe presumably has it's own power supply, which will almost certainly be solar panels. Their lifetime? Their power output? Fuel for station-keeping and orbit correction?
It's not so simple. I would like it if it were that simple, but it's not.
They volunteered ; why should they expect additional protection?
(And FYI I have a close relative who has recently been stupid enough to sign up and is currently in Afghanistan getting shot at. None of which changes the fact that he's been a bloody idiot and that he may die for it. And as an adult he's chosen to do something dangerous and unproductive, which is his choice. I'd understand it better if he was doing something fun like driving excessively fast or parachuting (for fun, not for pay), but it's his choice. I'm not obliged to support him though.)
I thought you programmer types enjoyed learning new languages.
(I do speak a little Russian, but nowhere near enough to even consider trying something like this.)
Actually, technically it probably is to a degree my problem - a major part of my work is in producing what are essentially special purpose vector drawings, fed off a large database. But again, since work supplies the software for me (or if a client wants to use something else, they provide it, a dongle, and a manual), that's not a problem.
OK, I suspect that you were making a joke. I'm not.
Oh, and by the way ; if I were to expend significant effort on thinking of methods of earthquake prediction or of prevention (or less unlikely, reduction in intensity), I'd concentrate on the important areas for preventing death and suffering - the Ganges valley and Himalayan foredeep - where confidently predictable death tolls from the confidently predictable "big one" are in the tens of millions. Or more. For your information, such a quake appears to be decades if not a century overdue, judging from the historical record.
I really do not want to know how you know what fucking a blackberry bush is like.
OK, I do. If it's a youtube video or something.
I'll just go and prepare some red-hot teaspoons, I fear I may need to scoop my eyeballs out.
It's not unlimited, and it's not free. The intensity of sunlight at any particular position in the solar system is more or less constant but finite. So you can increase the power available to you by increasing the area of your collector, until you have a Dyson Sphere. BUT, the weight you have to put into orbit (more precisely, "into this particular orbit") will increase more-or-less linearly with the area of the collector. And putting weight into orbit is not free.
Let's not even get into the fact that solar cells do degrade with time.
The solar energy available may be considerable, and the per-unit cost low, but it's not unlimited and it's not free.
You'd need to put your beam weapon into an orbit at similar altitude to the debris you're aiming at. Otherwise, the Earth is going to form a backdrop to your beam. OK, maybe you'll be lucky and only burn out the eyes of a third-world farmer instead of the remaining pilot of Queen Kathrine's plane. But maybe it's better to not take that risk?
I'd put my beam weapon in a relatively low orbit, and fire upwards at debris as it approaches it's apogee (highest orbital point w.r.t. Earth) reducing it's kinetic energy and so lowering it's perigee (lowest orbital point) and making it's orbit more eccentric; it will then lose more energy each time it goes lower ... until it eventually burns up. You might need to make several applications of the beam to control it's fall location - the south Pacific is popular.
No more debris in the appropriate orbital regions? Use your power supply and some trailing cables to pul your beam weapon into a different orbit by acting on the magnetic field. Lather, rinse, repeat.
Whether it would work sufficiently economically? I don't know. Is it impossible? I think not.
Your definition may cause you no problems when communicating with yourself. However since the general purpose of communication is to communicate with others, then it becomes necessary to stick reasonably closely to what other people mean by words. Consult Tweedledum and Tweedledee for further discussion (not debate).
An example : I am a geologist, and I pay some fair amount of attention to seismology because it's interesting, and understanding how energy moves through the Earth is a (minor) part of my day-to-day work. Compared to 99.9% of the population, that makes me very well informed on seismology and earthquake studies ; I could make a fair case for being considered an expert.
I do not have, and do not know of any credible expert (by my definition) seismologist who claims to have, any solution to the problem of predicting if there is going to be an earthquake of more then magnitude X in geographical region Y in future time period Z.
By your standards, there are no experts in seismology.
Do you know of any credible experts in interstellar travel? Or faster-than-light travel?
Your book is your book. But other people use different books.
... the theocracy is the biggest business around?
Let alone the difficulty of spotting someone under the influence of oxytocin. Or adrenaline (looks rather like various amphetamines).
Never used any of them (one is an IM product? I've had to use IM sometimes at work, but I simply don't see the point.).
Do you find any problems with using these when you're outside the US? I'm assuming that you have a US-location set up on your systems so that most of the sign-up issues are not valid. And when I go to work in Norway next week, I'll be in the US as far as the Internet is concerned.
Skype per se isn't so hard to duplicate ; it's user base is. And it's user base is precisely why I chose to go with Skype.
And I'll then be demanding refund of the unused part of my subscription, as well as some explanation of how I'm going to use my advertised online number now that they've shut down access to it.
Of course, if they continue making it accessible through Linux, no real problem. I'll still distrust M$, but if they don't slam the door on this product, then I'm not rabid enough to leave on that basis.
Will be interesting to see what actually happens. And I'd better start to investigate alternatives.
Cyclohexane is a cyclic hydrocarbon with a different formula to hexane (C6H12, versus C6H14). Cyclohexane isn't aromatic either.
CyclohexEne (note emphasis) is an unsaturated cyclic hydrocarbon, formula C6H10. It isn't aromatic either.
Cyclohex-di-ene describes two closely related unsaturated cyclic hydrocarbons, each with two non-adjacent double carbon-carbon bonds, formulae C6H8. One form will have some delocalisation of the electron quadruple, but whether that makes it aromatic could probably occupy a degree-level exam answer.
Cyclohex-tri-ene is an unsaturated cyclic hydrocarbon with full delocalisation of all the bonding electrons around the ring. It's better known as benzene.
I don't know, I've never seen an unpolluted area.
(I have worked on 4 continents, up to several hundreds of miles from the nearest street light, which might qualify as "less polluted" areas, but not "unpolluted" by any means.)
Did you read your ballot papers for last week's election? Mine had three - count them, three - different variants on the resurgent Nazi Party.
Come back in a century and you might well see that the Nazis are back in power and regretting their temporary setback in the second half of the twentieth century.
So, unless the inhabitants are deliberately precessing it - to signal? - using the attitude jet system, it's going to be very stable. So if we're seeing the star today, we'll be seeing it tomorrow and on into the future, unless the normal processes of galactic circulation takes us into the part of space occulted by the Ring (as seen from the star), we're unlikely to see any significant change.
Actually, this is inherent in the stories (and I've enough confidence in Larry Niven to have done his homework, or at least to have had his numbers checked since the embarrassment of that song to expect him to be right on this) : the Pak built the RingWorld (sorry, am I spoiling things for people who haven't read the whole series?) for protection against the Core Explosion. So they expected it to stay properly oriented w.r.t. the Core over inhumanly-long time scales.
There is a minor caveat : the shadows of the Shadow Squares will overlap the edges of the Ring significantly - otherwise there would be parts of the Ring without a day-night cycle. Therefore there would be two narrow regions with the on-off signal of the Shadow Squares. Which would be interesting, particularly since the Shadow Squares can have their spacing changed from the Repair Centre. That would provide a very difficult-to-interpret signal.
Discuss?
I was expecting to find out what their real limits were and then negotiate an appropriate rate, or trim my storage to an appropriate size. I didn't expect an immediate uncompromising shut-down.
So, off to Flickr for a paid account, and upload all the photos there. $25/year for unlimited, they say, and I know I'm nowhere near their limits.
Coincidentally, I was just driving past the Scottish home of Thomas Glover, "the Scottish Samurai", who was an engineer and merchant involved in the start-up of what eventually became Mitsubishi Corporation. He was responsible for the import of Japan's first locomotive, and thus indirectly for the choice of the commonest gauge of line in the country.
That's an interesting thought experiment. I have to spend some time on the bus soon - an excellent thing to think about.
Can you back up "most jurisdictions" with some numbers? I wouldn't even be sure of it being a majority for "any" data. I know for sure that certain personal medical information the doctors here are obliged to report to the relevant authorities.
I also remember cases such as the infamous "Typhoid Mary" that suggests that the situation in your locality may not be exactly as you paint it ; sometimes limits to personal liberty are perfectly reasonable.
[None of which considers the difference between what the law says should happen and what actually does happen ; different question.]