I think the "rule of thumb" in the UK at least is that
There is no "rule of thumb" for the UK.
I'm not sure what the rules are in England and Wales. In Scotland, I believe that it's a matter of contract with whoever you lease the lair from. As long as your descendants continue to pay the ground rent on the lair, then it's safe from disturbance (barring errors). Stop paying, and if the ground has had enough time to decompose a body - which varies with latitude, altitude (temperature) and soil properties - then they'll happily re-lease the ground after a few decades. If they find bones, they'll stop digging (if the hole is deep enough (3 or so ft) and all that the lair. Or, if the lair is too shallow, they'll dig through to make a deep lair, then put the bones back in, cover with soil and then continue the burial.
I had a friend who was a grave digger for a couple of years. That's Perthshire rules - I wouldn't bet on the rules being the same in neighbouring counties. Why would one expect them to be the same?
You're a moron:
https://www.gov.uk/government/... [www.gov.uk]
Wrong country, moron.
Also wrong argument. If you expect research or data to move a petty bureaucrat jobsworth, then you have no experience of the Real World.
I've never had to deal with Auld Reekie's Council, but dealt with others in the past. The planning and building approvals departments are "an experience". And not a nice one. Plus, of course, if you don't follow their dictates, they'll let you build what you want, then send their boys round (with the police to enforce it) to demolish your building and restore the site, then send you the bill. And bankrupt you if you don't pay it with a smile.
Hmmm, spent much time in rural Scotland in the last couple of decades? Very cosmopolitan region. Maybe not so cosmopolitan as a large city, but more cosmopolitan than a housing estate in a medium-sized town.
We have to start working on it *now*, so that in 50 years we have the experience to build the space factories
[Glum] Which will be fuck-all use when we spot the incoming dinosaur-killer asteroid due to touch down in 53 years.
(By "dinosaur-killer", I mean the current dinosaurs currently sitting on a lamp post squawking at each other outside the house. Not their bigger, already fossilised cousins.)
The process of making a burger is already highly automated. The problems you're talking about are mostly those of dealing with the meat. By which I mean the humans, not whatever goes between the bits of bread.
Of course there are reasons. Imagine your population is growing,
Didn't you read the bit in your contract of employment? The one that said "In the event of a pregnancy, the perons not carrying the foetus donates their air supply to the pregnant person (and foetus) and is escorted to the nearest airlock for a short walk outside. As per normal, your meat will then be taken down to the worm farm for recycling."
The launching part is relatively easy, as you can tune the operating parameters so that the wheel is essentially rolling across the top of the atmosphere, presenting a momentarily stationary and easily predictable point for pickup,
In contra-point, 50 years ago the first spy satellites dropped canisters of film (remember - silver halides on plastic sheet) and they were successfully caught in mid-air from $SOME BOMBER$.
It sounds like rocket science, but it's well-established rocket science.
I know people get excited about L1 and L2 and low-energy transfers,
Yes, but not for the reason you're looking at.
Say you're on Earth and you hear that a robotic tug bringing a 500m diameter lump of asteroid belt to LEO has malfunctioned, and will be 500km off from it's target location/ time/ velocity heptuple. And that 500km error will plant it into an ocean that borders your home. you are advised to take your suicide pill sometime in the remaining month before your death.
Miss your target by $DISTANCE$ when aiming for one of the L-points and more likely than not the worst outcome would be a fine from the Parking Warden.
which isn't going to make sense for human spaceflight,
The papers are not about performing human spaceflight. They're about building the space-based infrastructure that would allow human space flight at a negligible cost, while simultaneously building power stations for Earth, possibly compute-stations for Earth. Maybe sun-shields at L1 to take 1-2% off solar irradience and maybe save the Arctic from melting. Human space flight (e.g. a geological exploration mission to Mars or Io) is way down the list of priorities.
at least until we can reliably solve the gravity and radiation issues, both of which are only solved long-term with lots of mass.
There is a physically-possible plan for solving either plan that doesn't involve large amounts of mass? Enlighten me!
Why are you hung up on reducing oxides to metals? Would that be the most efficient use of your resources.
You want materials with a high strength-to-weight ratio? Precisely why? Because you're used to designs that rely on high strength-to-weight materials? Is there a different way to achieve your production aim?
The famous Bushveld complex is a concentration of platinum group metals thought to be caused by an asteroid impact melting into a magma body and then selectively crystallized out last as the magma body slowly cooled.
Strange then that the Bushveld's mineralogy matches very closely with multiple other cumulate deposits from Scotland to Norilsk to Greenland (thinking of ones whose thin sections I've examined myself), and the basement below the Bushveld doesn't sow the characteristic shattering of meteorite impact structures. (You could make a better case for Sudbury, but even that it is debated if much impactor material was left. For moderate impacts, essentially all of the impactor is blown out of the crater by the expansion of the vapourised impactor leading-edge and some vapourised planet bedrock. Most of the material comes down, but spread across between half and two hemispheres of the planet.
It is easy to underestimate how violent an asteroid impact is. When we next have one closer than Jupiter, people are going to have a real brown-trouser moment.
the Moon is made out of Earth's crust, so primarily consists of the lighter materials.
More accurately the Moon is formed from the Earth's mantle. When the Giant Impact happened (which remains the most-likely formation scenario for the Moon), the Earth hadn't significantly differentiated it's SIALic crust ("granite" to a non-geologists approximation ; IAAG and can go into this in nuseating detail if you want) and SIMAic mantle. So what got thrown up was largely mantle material.
The main difference between Lunar and (bulk-) Earth compositions is that the Moon is considerably depleted in "volatile" elements : carbon, as you say, sodium and potassium (compared to calcium and magnesium), sulphur and phosphorus (compared to selenium and arsenic). This is also visible in, for example patterns of rare-earth elements, whose monotonous chemistry makes other differentiation processes hard. These are taken as fairly good evidence that much of the Moon passed through a stage in the vapour phase - presumably in the impact debris plume before a debris ring formed.
and I'd add computation as the fourth item to the mix.
Computation is expressly considered in one or other of the papers.
In the very long run (think thousands of years!), it may yet turn out that we have no other choice.
I think it's more of a thousands of weeks issue, not a thousands of years issue. It could happen within your lifetime. It's not even inconceivable within my lifetime, if I stop smoking.
Bulk rock is easy for surface locations, and not so hard for orbital ones. Enough thickness will provide good shielding.
For radiation shielding, yes.
To a first approximation, what matters is mass, not composition. We live at the bottom of an atmosphere equivalent to about 10m of (sea) water. You can achieve that shielding with about 3m of compacted silicate dust. Or about 2/3 m of lead. Still adds up to much the same mass, so you use the most available stuff.
Most illustrations of space colonies are "artist's concepts" and don't address safety in the way engineers building bridges and skyscrapers have to. A real colony would have multiple layers of pressure shell, compartmentalization, emergency shelters, and other safety provisions.
My personal preference for shielding is to make lots of plastic bags, fill them with salty water melted out of your pet asteroid, or coarse or fine dust filtered from the water as the first stage in your processing. Attach bags to outside of space ship, in overlapping layers. Micrometeorite punctures a dust bag - big fucking deal - you've a thousand more around you. Punctures a water bag - it's already frozen to ice ; big fucking deal, as above.
Started building metal-rock paels for the next chunk of your space station? Well, start building it around the outside of your existing shield, maybe moving dust bags off so there are only water bags in between the layers. Then puncture the water bags and use it for leak detection, or just to mop up the dust. Eventually you have a shell with no major leaks, inside which you can start to build your next bit of living space, while pumping the remaining water bags out to add to the shielding.
It's do-able. Not significantly more hazardous than working on oil rigs (which I've done for nearly 30 years).
there were no tests for actual fitness -- a requirement for evolution.
The "landscape" of different concentrations of antibiotics in the MEGA-dish provides the test of thickness. The bacteria don't (on the timescale involved) diffusively move by more than a few millimetres on this metre-scale Petri dish. So the spread of colonies by tens of millimetres to tens of centimetres is accomplished by mummy (or daddy) bacteria loving other bacteria very much... oh, sorry, no - completely ignoring each other... and producing little baby bacteria which can survive in the hostile antibiotic landscape if they have the right mutation.
That differential survival of offspring is what defines "fitness". Fitness is always local to the environment. It doesn't have any predictive ability, otherwise the ancestors of humans who live 100 millennia now (i.e. your children, should you choose to have any) would already be developing the "fitness" they'll need to survive by breathing vacuum.
Are you one of those people who believes in an invisible sky fairy to justify your existence, and your fear of homosexual marriage?
has anyone compared the DNA of the final generations
Yes they did. It's in the Science paper at http://science.sciencemag.org/... (Sci-hub at http://science.sciencemag.org....) They sequenced several hundred of the mutant strains, plus, of course, multiple isolates of the wild-type strains (as wild types drift, even without deliberately applied evolutionary pressures).
to determine if they are genetically identical or radically different?
To no-one's surprise, when they sequenced up to a dozen isolates in a lineage which negotiated their "antibiotic landscape," they found small differences between individual isolates.
The paper is worth reading because your next three questions are probably answered before you formulate them.
Or, more speculatively, you could posit that there was some dynamical event that happened to the cluster since its formation that mixed the stars, so mass segregation has not had as long to operate as we assume.
Would the accretion of the globular cluster (or mini-galaxy) into the Milky Way be an appropriate event? Or the crossings of the globular cluster through the disc-plane of the Milky Way?
Thanks for the summary. My reading left considerable doubt over the models of the strength of "kick" that black holes receive in their formation SNe - how well tested are those models? Also, models of turbulent "viscosity" to damp down such motions are going to be replete with assumptions, which makes me suspicious of that aspect too.
It might be a good idea for you to actually read the abstract, or even (shock, horror!) the paper. The non-paywalled link is given upthread. You've completely misunderstood the situation being studied, the work that was done, and the conclusions reached.
I haven't been wasting time on this, since I've not changed my S5 for about 2 years now, and I'm not particularly interested in going to anyone's bleeding edge.
Are you saying that the problem is actually between S7 phones (and S7-batteries, supplied by Samsung) and SAMSUNG-supplied chargers, or between S7s (etc) and third-party chargers?
Since the phone is less than 4 years old, then charging is via a micro-USB connector. So if it's charged with a Samsung micro-USB charger, then that's certainly something that Samsung should check. And a few other third-party micro-USB chargers, including ones that go to the limits of the micro-USB specification. And ones that go to the outer limits of the error bars on the micro-USB specification. And then that's it. If you use a non-Samsung micro-USB charger which doesn't conform to the micro-USB specification, then is that Samsung's problem?
Number of combinations - S7 +Samsung charger ; S7 + 3rd party USB-low charger (or bench power supply set to low side of USB specification, probably safer in the lab) ; S7 + 3rd party USB-mid charger (similar, set to the mid-point of the specification) ; S7 + 3rd party USB-high (you know what I mean). 4 suites of tests. I'd actually test the Samsung charger a bit more - how does it react if plugged into 230, 250, 260 V AC mains, and also for American maybe 100, 110, 120 volts. 45-through 65 Hz at some spacing. But that should be the limit of the testing that you really need.
If a third-party supplier produces a "micro-USB charger" that puts 4x stepped up mains voltage down the power lines of it's connector, is that really Samsung's fault? By installing a micro-USB socket, are they not doing enough to prevent the reasonable end user from plugging it into dangerous voltages and currents?
Slashdot Mirror
There is no "rule of thumb" for the UK.
I'm not sure what the rules are in England and Wales. In Scotland, I believe that it's a matter of contract with whoever you lease the lair from. As long as your descendants continue to pay the ground rent on the lair, then it's safe from disturbance (barring errors). Stop paying, and if the ground has had enough time to decompose a body - which varies with latitude, altitude (temperature) and soil properties - then they'll happily re-lease the ground after a few decades. If they find bones, they'll stop digging (if the hole is deep enough (3 or so ft) and all that the lair. Or, if the lair is too shallow, they'll dig through to make a deep lair, then put the bones back in, cover with soil and then continue the burial.
I had a friend who was a grave digger for a couple of years. That's Perthshire rules - I wouldn't bet on the rules being the same in neighbouring counties. Why would one expect them to be the same?
Wrong country, moron.
Also wrong argument. If you expect research or data to move a petty bureaucrat jobsworth, then you have no experience of the Real World.
I've never had to deal with Auld Reekie's Council, but dealt with others in the past. The planning and building approvals departments are "an experience". And not a nice one. Plus, of course, if you don't follow their dictates, they'll let you build what you want, then send their boys round (with the police to enforce it) to demolish your building and restore the site, then send you the bill. And bankrupt you if you don't pay it with a smile.
Hmmm, spent much time in rural Scotland in the last couple of decades? Very cosmopolitan region. Maybe not so cosmopolitan as a large city, but more cosmopolitan than a housing estate in a medium-sized town.
Maybe - maybe not. Is "blackboard" politically incorrect?
[Glum] Which will be fuck-all use when we spot the incoming dinosaur-killer asteroid due to touch down in 53 years.
(By "dinosaur-killer", I mean the current dinosaurs currently sitting on a lamp post squawking at each other outside the house. Not their bigger, already fossilised cousins.)
The process of making a burger is already highly automated. The problems you're talking about are mostly those of dealing with the meat. By which I mean the humans, not whatever goes between the bits of bread.
Didn't you read the bit in your contract of employment? The one that said "In the event of a pregnancy, the perons not carrying the foetus donates their air supply to the pregnant person (and foetus) and is escorted to the nearest airlock for a short walk outside. As per normal, your meat will then be taken down to the worm farm for recycling."
Feel free to plug more.
Is it an in-class or on-line course? Will it be available again?
In contra-point, 50 years ago the first spy satellites dropped canisters of film (remember - silver halides on plastic sheet) and they were successfully caught in mid-air from $SOME BOMBER$.
It sounds like rocket science, but it's well-established rocket science.
Oh hi Dr Phil. Worth the effort of visiting?
Yes, but not for the reason you're looking at.
Say you're on Earth and you hear that a robotic tug bringing a 500m diameter lump of asteroid belt to LEO has malfunctioned, and will be 500km off from it's target location/ time/ velocity heptuple. And that 500km error will plant it into an ocean that borders your home. you are advised to take your suicide pill sometime in the remaining month before your death.
Miss your target by $DISTANCE$ when aiming for one of the L-points and more likely than not the worst outcome would be a fine from the Parking Warden.
The papers are not about performing human spaceflight. They're about building the space-based infrastructure that would allow human space flight at a negligible cost, while simultaneously building power stations for Earth, possibly compute-stations for Earth. Maybe sun-shields at L1 to take 1-2% off solar irradience and maybe save the Arctic from melting. Human space flight (e.g. a geological exploration mission to Mars or Io) is way down the list of priorities.
There is a physically-possible plan for solving either plan that doesn't involve large amounts of mass? Enlighten me!
[OP here.] Agree on pretty much all points.
You want materials with a high strength-to-weight ratio? Precisely why? Because you're used to designs that rely on high strength-to-weight materials? Is there a different way to achieve your production aim?
Strange then that the Bushveld's mineralogy matches very closely with multiple other cumulate deposits from Scotland to Norilsk to Greenland (thinking of ones whose thin sections I've examined myself), and the basement below the Bushveld doesn't sow the characteristic shattering of meteorite impact structures. (You could make a better case for Sudbury, but even that it is debated if much impactor material was left. For moderate impacts, essentially all of the impactor is blown out of the crater by the expansion of the vapourised impactor leading-edge and some vapourised planet bedrock. Most of the material comes down, but spread across between half and two hemispheres of the planet.
It is easy to underestimate how violent an asteroid impact is. When we next have one closer than Jupiter, people are going to have a real brown-trouser moment.
More accurately the Moon is formed from the Earth's mantle. When the Giant Impact happened (which remains the most-likely formation scenario for the Moon), the Earth hadn't significantly differentiated it's SIALic crust ("granite" to a non-geologists approximation ; IAAG and can go into this in nuseating detail if you want) and SIMAic mantle. So what got thrown up was largely mantle material.
The main difference between Lunar and (bulk-) Earth compositions is that the Moon is considerably depleted in "volatile" elements : carbon, as you say, sodium and potassium (compared to calcium and magnesium), sulphur and phosphorus (compared to selenium and arsenic). This is also visible in, for example patterns of rare-earth elements, whose monotonous chemistry makes other differentiation processes hard. These are taken as fairly good evidence that much of the Moon passed through a stage in the vapour phase - presumably in the impact debris plume before a debris ring formed.
Computation is expressly considered in one or other of the papers.
I think it's more of a thousands of weeks issue, not a thousands of years issue. It could happen within your lifetime. It's not even inconceivable within my lifetime, if I stop smoking.
For radiation shielding, yes.
To a first approximation, what matters is mass, not composition. We live at the bottom of an atmosphere equivalent to about 10m of (sea) water. You can achieve that shielding with about 3m of compacted silicate dust. Or about 2/3 m of lead. Still adds up to much the same mass, so you use the most available stuff.
My personal preference for shielding is to make lots of plastic bags, fill them with salty water melted out of your pet asteroid, or coarse or fine dust filtered from the water as the first stage in your processing. Attach bags to outside of space ship, in overlapping layers. Micrometeorite punctures a dust bag - big fucking deal - you've a thousand more around you. Punctures a water bag - it's already frozen to ice ; big fucking deal, as above.
Started building metal-rock paels for the next chunk of your space station? Well, start building it around the outside of your existing shield, maybe moving dust bags off so there are only water bags in between the layers. Then puncture the water bags and use it for leak detection, or just to mop up the dust. Eventually you have a shell with no major leaks, inside which you can start to build your next bit of living space, while pumping the remaining water bags out to add to the shielding.
It's do-able. Not significantly more hazardous than working on oil rigs (which I've done for nearly 30 years).
[SIGH] I post a link to the original papers, and then people don't read it. Sometimes I sympathise with "StartsWithABang".
The "landscape" of different concentrations of antibiotics in the MEGA-dish provides the test of thickness. The bacteria don't (on the timescale involved) diffusively move by more than a few millimetres on this metre-scale Petri dish. So the spread of colonies by tens of millimetres to tens of centimetres is accomplished by mummy (or daddy) bacteria loving other bacteria very much ... oh, sorry, no - completely ignoring each other ... and producing little baby bacteria which can survive in the hostile antibiotic landscape if they have the right mutation.
That differential survival of offspring is what defines "fitness". Fitness is always local to the environment. It doesn't have any predictive ability, otherwise the ancestors of humans who live 100 millennia now (i.e. your children, should you choose to have any) would already be developing the "fitness" they'll need to survive by breathing vacuum.
Are you one of those people who believes in an invisible sky fairy to justify your existence, and your fear of homosexual marriage?
[Sigh] for the third and final time of writing, your question is answered in the paper. It is trivial to find the paper.
Your question is answered in the paper. Unfortunately I've closed that tab so you'll have to look upthread to where I give the links to it.
Yes they did. It's in the Science paper at http://science.sciencemag.org/... (Sci-hub at http://science.sciencemag.org....) They sequenced several hundred of the mutant strains, plus, of course, multiple isolates of the wild-type strains (as wild types drift, even without deliberately applied evolutionary pressures).
To no-one's surprise, when they sequenced up to a dozen isolates in a lineage which negotiated their "antibiotic landscape," they found small differences between individual isolates.
The paper is worth reading because your next three questions are probably answered before you formulate them.
Would the accretion of the globular cluster (or mini-galaxy) into the Milky Way be an appropriate event? Or the crossings of the globular cluster through the disc-plane of the Milky Way?
Thanks for the summary. My reading left considerable doubt over the models of the strength of "kick" that black holes receive in their formation SNe - how well tested are those models? Also, models of turbulent "viscosity" to damp down such motions are going to be replete with assumptions, which makes me suspicious of that aspect too.
It might be a good idea for you to actually read the abstract, or even (shock, horror!) the paper. The non-paywalled link is given upthread. You've completely misunderstood the situation being studied, the work that was done, and the conclusions reached.
Are you saying that the problem is actually between S7 phones (and S7-batteries, supplied by Samsung) and SAMSUNG-supplied chargers, or between S7s (etc) and third-party chargers?
Since the phone is less than 4 years old, then charging is via a micro-USB connector. So if it's charged with a Samsung micro-USB charger, then that's certainly something that Samsung should check. And a few other third-party micro-USB chargers, including ones that go to the limits of the micro-USB specification. And ones that go to the outer limits of the error bars on the micro-USB specification. And then that's it. If you use a non-Samsung micro-USB charger which doesn't conform to the micro-USB specification, then is that Samsung's problem?
Number of combinations - S7 +Samsung charger ; S7 + 3rd party USB-low charger (or bench power supply set to low side of USB specification, probably safer in the lab) ; S7 + 3rd party USB-mid charger (similar, set to the mid-point of the specification) ; S7 + 3rd party USB-high (you know what I mean). 4 suites of tests. I'd actually test the Samsung charger a bit more - how does it react if plugged into 230, 250, 260 V AC mains, and also for American maybe 100, 110, 120 volts. 45-through 65 Hz at some spacing. But that should be the limit of the testing that you really need.
If a third-party supplier produces a "micro-USB charger" that puts 4x stepped up mains voltage down the power lines of it's connector, is that really Samsung's fault? By installing a micro-USB socket, are they not doing enough to prevent the reasonable end user from plugging it into dangerous voltages and currents?