Agreed. And perhaps most obviously, a reduction in population almost certainly means a redution in population density and personal stress, both of which reduce fertility rates in many/most mammals.
Even a 99% reduction in population from current levels wouldn't be real a problem (aside from the logistics of supporting a shrinking, elder-heavy population), in fact a return to 1800-level population would eliminate virtually all of the major problems our species is currently facing. And trying to project current trends into a world with with 100x more land and resources per person than today, along with the benefits of much-better-than-modern automation? Sheer foolishness.
Thing is, as I've mentioned to above, that is a problem has absolutely nothing to do with the viability of a desktop experience. Compulsive hoarding will always fill all available storage space, but store just a dozen fewer pictures, and you've got plenty of room for a large collection of desktop programs.
If you want to keep a huge media library on your phone, then yes, that's likely to interfere with using it as a desktop. But there's no reason everyone else would have to forgo that functionality on your behalf.
Besides, just one of those photos takes up far more space than a complete reasonably powerful office suite from the good old days of yore. Delete a second photo and you'd have room for dozens or hundreds of office documents. Or if you want something more modern, you can get a feature-rich word processor, spreadsheet, graphics program, etc, etc, etc in under a dozen MB each. Not MS- or Libre-Office, but those are huge bloated cows where most people don't use even 10% of the features.
Basically, storage capacity puts a limit on the size of your media library, NOT on your phone's ability to function as a desktop. (Storage *speed* on the other hand...). And your phone already has a big operating system on it - it's mostly just the small user-interface component of it that's not designed to be used as a desktop.
Forget scaling, just use the external monitor as a second screen at its native resolution - a 1080p TV works just fine as a monitor, and 4k is glorious.
The problem though is not only the finder/explorer "desktop", it's the entire interface philosophy - phone interfaces are designed around the incredibly crude and limited tiny touch-screen interface. At best it's a crude and clunky interface to navigate via mouse. I mean yeah, you could coax it to work for some things, especially assuming you stuck to a non-windowed "fullscreen only" philosophy for applications - maybe "windows key" for pulling up the active/recent programs display, and... "Alt" for the basic menu - but toolbars? Rich multi-level context menus? You need software designed for a desktop to deliver a desktop experience, which means you need an API that provides developers the UI widgets they need in a standardized, good-looking form. None of which will be compatible with the default crude touch-screen interface.
Now personally I don't see a major problem - you could get a LOT of work done with just full-screen programs, there are even a number of experimental desktop OSes that have intentionally gone in that direction, but it would mean that your phone is basically two separate UI platforms - touch-screen apps, and desktop programs. Apps would mostly run fine in a desktop mode, provided they didn't use multi-touch, though the crudity of the UI would be very obvious. Desktop programs though would mostly be completely unusable in touch-screen mode.
Still, it wouldn't be that hard to make desktop programs easy to identify so that you get a standard startup splash screen when trying to launch them in touch-screen mode: "This program is designed for the desktop and not recommended for touch-screen mode [Cancel] [Continue] [Do not warn me again]".
There's always room for improvement but - and this is the important question - how much slow-motion video do you shoot with your laptop? Shooting video is not really part of the typical "notebook experience" that I'm discussing.
"The 1TB eUFS is expected to play a critical role in bringing a more notebook-like user experience to the next generation of mobile devices,"
Raise your hand if you regularly use a computer/laptop with far less than 1TB of hard disc/SSD capacity.
Even relatively cheap smartphones have had plenty of storage, RAM, and processing power to deliver a compelling desktop experience for years. The problem is not a lack of storage space, it's a lack of a desktop-oriented operating system. A tiny screen and horribly crude default I/O devices don't help either, but bluetooth peripherals and/or a USB-C dock can (potentially) solve that nicely
>attempts at water cooling them have given disappointing levels of improvement
Perhaps so - but that picture might look much better when it comes to keeping them cool and damage free when used with a concentrator. Your water cooling system can also be capturing a lot more energy than the PV cells themselves, if you have a use for heat.
Ah, yes. If you're planning to carry enough fuel for the return trip, that does alter the picture quite dramatically. Though even without fuel manufacturing on Mars, there is the option of sending one or more fuel tanker rockets ahead on a much more fuel-efficient trajectory, so that you can refuel in Mars orbit, both before landing and again before returning to Earth. You can even still use the atmosphere for braking to orbital speeds.
Agreed. However, the practical maximum is a LOT faster than needed for a Hohmann transfer orbit. And as an added bonus the faster you go, the less distance you have to travel, since you don't have to travel nearly as far around the sun. (even as measured from the rotating Earth's-orbit frame we start in)
Besides which I've not heard any of the experts challenge Musk's claim that a 60-90 day transit time is practical to achieve. That tells me it's not even getting severely close to the practical limits for a rocket of that size. Heck, past Mars missions fall in the range of 158 to 333 days to make the trip, and they've all been flights directly from the Earth's surface, with no orbital refueling and all the much more drastic limitations that puts on the mission profile.
That would work great, if we had any way to see such objects. Before we went to visit up close and personal, this is one of the best photos we had of Pluto, a planet ~2400 km across. https://www.jpl.nasa.gov/space...
A still-huge rock 1 km across would be about 6 million times smaller and dimmer (assuming the same surface albedo). It'd barely show up as a single very slightly less black pixel. More typical sized rocks in the 10-100m diameter? That's another 100x to 10,000x smaller and dimmer still. We wouldn't have a clue they were there.
Also, there's no "steady stream of objects" implied, not from a human perspective anyway - at Pluto's orbital distance things are moving less than 1.5 degrees per year. And with a mass 10x Earth, spread out around an orbit that could hold a "necklace" of 3 million Earths, there's not necessarily going to be much in any give spot. Especially when you consider that the thickness of the Kuiper belt (perpendicular to the planetary plane) is larger than the diameter of Earth's orbit.
Actually there is no maximum delta-V implied - delta-V increases with the logarithm of the fuel mass, and the logarithm increases increasingly slowly, but without any upper bound. In practical terms though the exponential increase in fuel requirements makes the diminishing returns unlikely to be worth it beyond some point.
You are right that we probably couldn't realistically make the trip in a few weeks with current technology though.
However, the typical Mars mission takes only ~150-300 days to reach Mars, and that's in a craft that launched directly from Earth's surface. Stop to completely refuel in high Earth orbit instead, as is a common feature of proposed crewed Mars missions, and your available delta-V increases dramatically.
Probably so - crunch time means everyone is working burnt out, which means they have more trouble fixing bugs, and are more likely to introduce new ones.
Plus the fact that it's been repeatedly shown that doing mental work for more than about 30-40 hours per week on a regular basis actually *decreases* per-week productivity as the hours worked increase
The carbon tax-and-rebate plan has been circulated for a while now - in fact I think it was one of the earliest proposals. And one variant has been proposed and possibly passed in Canada. It doesn't get nearly as much press as I think it deserves it deserves though - and you can decide how cynical you want to be about that. With oil money as prominent as it has been (and still is) in politics, it seems likely that easily gamed systems probably get a lot more support.
You're right that conclusive answers are difficult, especially since all our data about precious events only exists in the fossil record, with even the most recent happening millions of years ago. However, it seems likely that far more people would suffer than benefit, for two main reasons:
Firstly, because during the transition the climate will be extremely unstable, which makes weather unpredictable, and farming far less productive on average - you need to know what this year's weather is going to be like in order to decide what kind of crop to plant - and as historical norms (even last year) become increasingly irrelevant to that question, the odds of planting the wrong crop increase dramatically.
Secondly most of the global population lives in what we would consider abject poverty, mostly in regions that will probably become a lot less hospitable as the climate changes, and mostly with a lot of infrastructure that will be lost to sea level rise. They can't afford to adapt, and available evidence is that the rest of the world is unwilling to feed them or accept them as refugees, and that seems unlikely to improve as we start feeling the effects more strongly ourselves.
There will almost certainly be climate winners though - Canada and Russia will likely both become far more temperate and lush, which is probably at least part of why Putin shows no interest in curbing emissions. Canada in contrast has that pesky well-armed and war-mongering southern neighbor to worry about.
As you say, you can make the trip as short as you want, you just need to reduce the payload. And while hundreds of days is perfectly acceptable for hardware, it's not for humans, so we wouldn't do it that way.
The alternative to getting there fast, is radiation shielding, which basically means at least a few pounds per square inch of surface, and preferably several. 14.7psi will get you Earth-atmosphere class radiation shielding, since radiation shielding effectiveness is directly proportional to mass, and only lightly affected by density, but that translates to a shell of rock 3.9 meters thick. As a back-of-the-napkin calculation: The SpaceX Starship has a pressurized volume of ~1000m^3, which if it were a minimum-surface sphere would be 483 m^2, or 749,000in^2 . For convenience lets call it an even million square inches for the definitely-not-spherical rocket. That means a million pounds for each 1psi of radiation shielding - or ~5x the payload to orbit. Put enough shielding on the thing to keep people safe, and you'll never get off the ground, so you'd have to install it in orbit, and even than would make the delta-V to reach Mars outrageous.
So instead we have to go light. Not much shielding, not much payload, and fly like the devil himself is on your heels.
Absolutely - but nobody is proposing low energy transfer orbits to get to Mars. You might send cargo that way, but even if the crew survived their health would be permanently devastated. Plus you'd need a lot more supplies and possibly a recycling system on board, which would slow things down dramatically. Take the same rocket with just the crew and minimal supplies and you'd get there a lot faster.
Not so. The proposed planet nine to explain the unlikely clustering of TNOs would have a period in the 10,000-20,000 year range https://en.wikipedia.org/wiki/...
By Kepler's Law (T^2 proportional to R^3), that would put it's semi-major axis at between 464 to 737 AU, and its apogee could be almost twice that.(semimajor axis is the average of apogee and perigee)
Assuming it basically looks like Pluto scaled up 11-23x (to the estimated 2-4x the Earth's diameter) Would mean it's angular diameter would be between (11x)*40AU/737AU = 0.6x and (23x)*40/464 = 2.0x the size, for an angular area between 0.36x and 4.0x Pluto, and a corresponding effective brightness between 0.6*(40/737)^2= 0.2% and 4.0*(40/464)^2=3% as bright as Pluto. Assuming a circular orbit - it might be far smaller and dimmer at apogee.
Easy to overlook. Especially since it would move only 0.02 to 0.04 degrees per year. Or potentially much less it it's near apogee.
Where are you getting 438 days? Every proposal I've seen for sending humans to Mars has transit times in the range of a few months to a few weeks,depending on payload. Assuming we sent a SpaceX Starship carrying only a few people and only enough supplies to reach Mars (having sent the rest of the supplies ahead of time) you could cut the transit time way down.
And once you're on Mars (or the Moon), radiation pretty much stops being an issue unless you're stupid about it. A few meters of rock or twice that of sand offers as much radiation protection as the Earth's atmosphere, and we don't actually need that much to be reasonably safe.
I would assume that they assume a elliptical torus of uniform density, (or possibly with some variation between perigee and apogee). That seems to be the usual approximation of rings.
Stable orbits with respect to each other is rather the norm, is it not? After all, at a given distance from the primary, everything must be orbiting at the same speed.
Rings are one of the most common mass distributions we see, and (so long as they're well outside the Roche limit) we don't completely understand why they do or don't consolidate into larger bodies. At any rate, if they *do* consolidate, it's presumed to take 10s to 100s of millions of years, and I can't find any information on whether that's influenced by the orbital period - if it is then at 30-50 AU, where orbits are in the 164-353 year range, it might take many billions of years for an Earth-sized planet to form, and it would still be in the early stages of the process.
Plus, a radically lower mass density per cubic kilometer probably doesn't help anything - assuming a ring had 10x the total mass of Earth, it would have at best 1/3 to 1/5th the density of Earth's proto-planetary ring, and far, far lower if the radial width of the ring was several AU. That far from the primary the ring flattening effects would be much weaker/slower as well. All together, the density could easily be thousands or millions of times lower than Earth's protoplanetary disc, which would (presumably) make planet formation much less likely.
>Yes, but that was an idiotic idea because we could actually find it if it were that large
Hardly - the thing could easily be on a highly elliptical long-period orbit, in which case we might only see it near it's closest approach, which could currently be hundreds or thousands of years away. Or we might not be able to see it at all, if it's surface was unusually dark.
I think it's safe to say anyone making that CO2 claim is misinformed or an idiot. No shortage of those on either side of the debate. CO2 is toxic in high concentrations, but 350-1,000ppm is typical of a moderately well-ventilated indoor space. Over that it starts feeling stuffy and you start feeling drowsy, and from 2-5,000ppm you'll start suffering headaches, sleepiness, poor concentration, lack of attention, and possibly nausea. Getting above 40,000ppm (4%) starts seriously interfering with oxygen uptake, causing brain damage, coma, and even death.
As for the severity of the transition - what I'm saying is that there *is* precedent. The planet has swapped from one state to the other several times, and it's always been a bad ride. And no, the transition doesn't take millions of years, it happens geologically overnight, - it's just been millions of years since the last one. And the faster the transition, the greater the environmental devastation is likely to be - trees can't migrate quickly as climate lines move, soil microbes don't necessarily do much better, and without those the ecosystem is in rough shape. Ocean diatoms don't do well as acidity increases , and are a major source of global oxygen. And animal's instincts don't necessarily allow them to adapt. Human intelligence might be able to mitigate such problems, but it'd likely make the cost of getting off fossil fuels pale in comparison.
I can't say I'm a fan of carbon credit trading, unsurprisingly the system was practically designed to be gamed, and so it is. If we're looking for an "easy" legislative solution I'd much rather see a fossil carbon tax-and-rebate system: tax all fossil fuels at the time of extraction or importation, and distribute that revenue equally to the population. Those costs get passed on, so the prices of everything go up, but so long as your personal carbon energy footprint is below average, your rebate more than offsets those changes and you come out ahead (and that almost certainly includes most of the poor). And most importantly, everyone at every point in the supply chain has an immediate competitive financial incentive to prefer cheaper non-fossil energy. As that happens revenue and rebates diminish, but so does the average cost of goods, putting the entire population in a continuous "lower my carbon footprint" competition to stay below average and turn a profit. Obviously properly taxing the carbon footprint of imported goods would require either rough tariffs, or an international agreement on carbon tax rates.
Sure, but malware on the phone is a secondary problem - anyone that has to resort to those tactics is a relatively minor threat to your freedom.
Still, something that I'd be all for - absolutely no sense making it easy for people. Personally I rarely have a use for GPS, and keep location information turned off on my phone for exactly that reason.
Breakeven is actually the easier "theoretical" milestone to reach - ignition is more difficult as it has to take into account environmental heat losses so that the reaction can be self-sustaining. Paragraph two on your link.
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Agreed. And perhaps most obviously, a reduction in population almost certainly means a redution in population density and personal stress, both of which reduce fertility rates in many/most mammals.
Even a 99% reduction in population from current levels wouldn't be real a problem (aside from the logistics of supporting a shrinking, elder-heavy population), in fact a return to 1800-level population would eliminate virtually all of the major problems our species is currently facing. And trying to project current trends into a world with with 100x more land and resources per person than today, along with the benefits of much-better-than-modern automation? Sheer foolishness.
Thing is, as I've mentioned to above, that is a problem has absolutely nothing to do with the viability of a desktop experience. Compulsive hoarding will always fill all available storage space, but store just a dozen fewer pictures, and you've got plenty of room for a large collection of desktop programs.
Three words: external hard drive.
If you want to keep a huge media library on your phone, then yes, that's likely to interfere with using it as a desktop. But there's no reason everyone else would have to forgo that functionality on your behalf.
Besides, just one of those photos takes up far more space than a complete reasonably powerful office suite from the good old days of yore. Delete a second photo and you'd have room for dozens or hundreds of office documents. Or if you want something more modern, you can get a feature-rich word processor, spreadsheet, graphics program, etc, etc, etc in under a dozen MB each. Not MS- or Libre-Office, but those are huge bloated cows where most people don't use even 10% of the features.
Basically, storage capacity puts a limit on the size of your media library, NOT on your phone's ability to function as a desktop. (Storage *speed* on the other hand...). And your phone already has a big operating system on it - it's mostly just the small user-interface component of it that's not designed to be used as a desktop.
Forget scaling, just use the external monitor as a second screen at its native resolution - a 1080p TV works just fine as a monitor, and 4k is glorious.
The problem though is not only the finder/explorer "desktop", it's the entire interface philosophy - phone interfaces are designed around the incredibly crude and limited tiny touch-screen interface. At best it's a crude and clunky interface to navigate via mouse. I mean yeah, you could coax it to work for some things, especially assuming you stuck to a non-windowed "fullscreen only" philosophy for applications - maybe "windows key" for pulling up the active/recent programs display, and... "Alt" for the basic menu - but toolbars? Rich multi-level context menus? You need software designed for a desktop to deliver a desktop experience, which means you need an API that provides developers the UI widgets they need in a standardized, good-looking form. None of which will be compatible with the default crude touch-screen interface.
Now personally I don't see a major problem - you could get a LOT of work done with just full-screen programs, there are even a number of experimental desktop OSes that have intentionally gone in that direction, but it would mean that your phone is basically two separate UI platforms - touch-screen apps, and desktop programs. Apps would mostly run fine in a desktop mode, provided they didn't use multi-touch, though the crudity of the UI would be very obvious. Desktop programs though would mostly be completely unusable in touch-screen mode.
Still, it wouldn't be that hard to make desktop programs easy to identify so that you get a standard startup splash screen when trying to launch them in touch-screen mode: "This program is designed for the desktop and not recommended for touch-screen mode [Cancel] [Continue] [Do not warn me again]".
There's always room for improvement but - and this is the important question - how much slow-motion video do you shoot with your laptop? Shooting video is not really part of the typical "notebook experience" that I'm discussing.
"The 1TB eUFS is expected to play a critical role in bringing a more notebook-like user experience to the next generation of mobile devices,"
Raise your hand if you regularly use a computer/laptop with far less than 1TB of hard disc/SSD capacity.
Even relatively cheap smartphones have had plenty of storage, RAM, and processing power to deliver a compelling desktop experience for years. The problem is not a lack of storage space, it's a lack of a desktop-oriented operating system. A tiny screen and horribly crude default I/O devices don't help either, but bluetooth peripherals and/or a USB-C dock can (potentially) solve that nicely
>The dumbest thing any human being can possibly do is to mess with the proper operation of their own brain for recreational purposes.
Which I assume is why you avoid alcohol, tobacco, aspirin, coffee, and the many other mind-altering drugs our spociety approves of as well, right?
>attempts at water cooling them have given disappointing levels of improvement
Perhaps so - but that picture might look much better when it comes to keeping them cool and damage free when used with a concentrator. Your water cooling system can also be capturing a lot more energy than the PV cells themselves, if you have a use for heat.
Ah, yes. If you're planning to carry enough fuel for the return trip, that does alter the picture quite dramatically. Though even without fuel manufacturing on Mars, there is the option of sending one or more fuel tanker rockets ahead on a much more fuel-efficient trajectory, so that you can refuel in Mars orbit, both before landing and again before returning to Earth. You can even still use the atmosphere for braking to orbital speeds.
Agreed. However, the practical maximum is a LOT faster than needed for a Hohmann transfer orbit. And as an added bonus the faster you go, the less distance you have to travel, since you don't have to travel nearly as far around the sun. (even as measured from the rotating Earth's-orbit frame we start in)
Besides which I've not heard any of the experts challenge Musk's claim that a 60-90 day transit time is practical to achieve. That tells me it's not even getting severely close to the practical limits for a rocket of that size. Heck, past Mars missions fall in the range of 158 to 333 days to make the trip, and they've all been flights directly from the Earth's surface, with no orbital refueling and all the much more drastic limitations that puts on the mission profile.
You're most welcome. I appreciate the opportunity to talk to somebody who's actually thinking about the issues.
That would work great, if we had any way to see such objects. Before we went to visit up close and personal, this is one of the best photos we had of Pluto, a planet ~2400 km across. https://www.jpl.nasa.gov/space...
A still-huge rock 1 km across would be about 6 million times smaller and dimmer (assuming the same surface albedo). It'd barely show up as a single very slightly less black pixel. More typical sized rocks in the 10-100m diameter? That's another 100x to 10,000x smaller and dimmer still. We wouldn't have a clue they were there.
Also, there's no "steady stream of objects" implied, not from a human perspective anyway - at Pluto's orbital distance things are moving less than 1.5 degrees per year. And with a mass 10x Earth, spread out around an orbit that could hold a "necklace" of 3 million Earths, there's not necessarily going to be much in any give spot. Especially when you consider that the thickness of the Kuiper belt (perpendicular to the planetary plane) is larger than the diameter of Earth's orbit.
Actually there is no maximum delta-V implied - delta-V increases with the logarithm of the fuel mass, and the logarithm increases increasingly slowly, but without any upper bound. In practical terms though the exponential increase in fuel requirements makes the diminishing returns unlikely to be worth it beyond some point.
You are right that we probably couldn't realistically make the trip in a few weeks with current technology though.
However, the typical Mars mission takes only ~150-300 days to reach Mars, and that's in a craft that launched directly from Earth's surface. Stop to completely refuel in high Earth orbit instead, as is a common feature of proposed crewed Mars missions, and your available delta-V increases dramatically.
Probably so - crunch time means everyone is working burnt out, which means they have more trouble fixing bugs, and are more likely to introduce new ones.
Plus the fact that it's been repeatedly shown that doing mental work for more than about 30-40 hours per week on a regular basis actually *decreases* per-week productivity as the hours worked increase
The carbon tax-and-rebate plan has been circulated for a while now - in fact I think it was one of the earliest proposals. And one variant has been proposed and possibly passed in Canada. It doesn't get nearly as much press as I think it deserves it deserves though - and you can decide how cynical you want to be about that. With oil money as prominent as it has been (and still is) in politics, it seems likely that easily gamed systems probably get a lot more support.
You're right that conclusive answers are difficult, especially since all our data about precious events only exists in the fossil record, with even the most recent happening millions of years ago. However, it seems likely that far more people would suffer than benefit, for two main reasons:
Firstly, because during the transition the climate will be extremely unstable, which makes weather unpredictable, and farming far less productive on average - you need to know what this year's weather is going to be like in order to decide what kind of crop to plant - and as historical norms (even last year) become increasingly irrelevant to that question, the odds of planting the wrong crop increase dramatically.
Secondly most of the global population lives in what we would consider abject poverty, mostly in regions that will probably become a lot less hospitable as the climate changes, and mostly with a lot of infrastructure that will be lost to sea level rise. They can't afford to adapt, and available evidence is that the rest of the world is unwilling to feed them or accept them as refugees, and that seems unlikely to improve as we start feeling the effects more strongly ourselves.
There will almost certainly be climate winners though - Canada and Russia will likely both become far more temperate and lush, which is probably at least part of why Putin shows no interest in curbing emissions. Canada in contrast has that pesky well-armed and war-mongering southern neighbor to worry about.
As you say, you can make the trip as short as you want, you just need to reduce the payload. And while hundreds of days is perfectly acceptable for hardware, it's not for humans, so we wouldn't do it that way.
The alternative to getting there fast, is radiation shielding, which basically means at least a few pounds per square inch of surface, and preferably several. 14.7psi will get you Earth-atmosphere class radiation shielding, since radiation shielding effectiveness is directly proportional to mass, and only lightly affected by density, but that translates to a shell of rock 3.9 meters thick. As a back-of-the-napkin calculation: The SpaceX Starship has a pressurized volume of ~1000m^3, which if it were a minimum-surface sphere would be 483 m^2, or 749,000in^2 . For convenience lets call it an even million square inches for the definitely-not-spherical rocket. That means a million pounds for each 1psi of radiation shielding - or ~5x the payload to orbit. Put enough shielding on the thing to keep people safe, and you'll never get off the ground, so you'd have to install it in orbit, and even than would make the delta-V to reach Mars outrageous.
So instead we have to go light. Not much shielding, not much payload, and fly like the devil himself is on your heels.
Absolutely - but nobody is proposing low energy transfer orbits to get to Mars. You might send cargo that way, but even if the crew survived their health would be permanently devastated. Plus you'd need a lot more supplies and possibly a recycling system on board, which would slow things down dramatically. Take the same rocket with just the crew and minimal supplies and you'd get there a lot faster.
Not so. The proposed planet nine to explain the unlikely clustering of TNOs would have a period in the 10,000-20,000 year range https://en.wikipedia.org/wiki/...
By Kepler's Law (T^2 proportional to R^3), that would put it's semi-major axis at between 464 to 737 AU, and its apogee could be almost twice that.(semimajor axis is the average of apogee and perigee)
Assuming it basically looks like Pluto scaled up 11-23x (to the estimated 2-4x the Earth's diameter) Would mean it's angular diameter would be between (11x)*40AU/737AU = 0.6x and (23x)*40/464 = 2.0x the size, for an angular area between 0.36x and 4.0x Pluto, and a corresponding effective brightness between 0.6*(40/737)^2= 0.2% and 4.0*(40/464)^2=3% as bright as Pluto. Assuming a circular orbit - it might be far smaller and dimmer at apogee.
Easy to overlook. Especially since it would move only 0.02 to 0.04 degrees per year. Or potentially much less it it's near apogee.
Where are you getting 438 days? Every proposal I've seen for sending humans to Mars has transit times in the range of a few months to a few weeks,depending on payload. Assuming we sent a SpaceX Starship carrying only a few people and only enough supplies to reach Mars (having sent the rest of the supplies ahead of time) you could cut the transit time way down.
And once you're on Mars (or the Moon), radiation pretty much stops being an issue unless you're stupid about it. A few meters of rock or twice that of sand offers as much radiation protection as the Earth's atmosphere, and we don't actually need that much to be reasonably safe.
I would assume that they assume a elliptical torus of uniform density, (or possibly with some variation between perigee and apogee). That seems to be the usual approximation of rings.
Stable orbits with respect to each other is rather the norm, is it not? After all, at a given distance from the primary, everything must be orbiting at the same speed.
Rings are one of the most common mass distributions we see, and (so long as they're well outside the Roche limit) we don't completely understand why they do or don't consolidate into larger bodies. At any rate, if they *do* consolidate, it's presumed to take 10s to 100s of millions of years, and I can't find any information on whether that's influenced by the orbital period - if it is then at 30-50 AU, where orbits are in the 164-353 year range, it might take many billions of years for an Earth-sized planet to form, and it would still be in the early stages of the process.
Plus, a radically lower mass density per cubic kilometer probably doesn't help anything - assuming a ring had 10x the total mass of Earth, it would have at best 1/3 to 1/5th the density of Earth's proto-planetary ring, and far, far lower if the radial width of the ring was several AU. That far from the primary the ring flattening effects would be much weaker/slower as well. All together, the density could easily be thousands or millions of times lower than Earth's protoplanetary disc, which would (presumably) make planet formation much less likely.
>Yes, but that was an idiotic idea because we could actually find it if it were that large
Hardly - the thing could easily be on a highly elliptical long-period orbit, in which case we might only see it near it's closest approach, which could currently be hundreds or thousands of years away. Or we might not be able to see it at all, if it's surface was unusually dark.
Except if Pluto is a planet, we should probably count at least Ceres as well, making Pluto #10, and requiring all the gas giants to be renumbered.
I think it's safe to say anyone making that CO2 claim is misinformed or an idiot. No shortage of those on either side of the debate. CO2 is toxic in high concentrations, but 350-1,000ppm is typical of a moderately well-ventilated indoor space. Over that it starts feeling stuffy and you start feeling drowsy, and from 2-5,000ppm you'll start suffering headaches, sleepiness, poor concentration, lack of attention, and possibly nausea. Getting above 40,000ppm (4%) starts seriously interfering with oxygen uptake, causing brain damage, coma, and even death.
As for the severity of the transition - what I'm saying is that there *is* precedent. The planet has swapped from one state to the other several times, and it's always been a bad ride. And no, the transition doesn't take millions of years, it happens geologically overnight, - it's just been millions of years since the last one. And the faster the transition, the greater the environmental devastation is likely to be - trees can't migrate quickly as climate lines move, soil microbes don't necessarily do much better, and without those the ecosystem is in rough shape. Ocean diatoms don't do well as acidity increases , and are a major source of global oxygen. And animal's instincts don't necessarily allow them to adapt. Human intelligence might be able to mitigate such problems, but it'd likely make the cost of getting off fossil fuels pale in comparison.
I can't say I'm a fan of carbon credit trading, unsurprisingly the system was practically designed to be gamed, and so it is. If we're looking for an "easy" legislative solution I'd much rather see a fossil carbon tax-and-rebate system: tax all fossil fuels at the time of extraction or importation, and distribute that revenue equally to the population. Those costs get passed on, so the prices of everything go up, but so long as your personal carbon energy footprint is below average, your rebate more than offsets those changes and you come out ahead (and that almost certainly includes most of the poor). And most importantly, everyone at every point in the supply chain has an immediate competitive financial incentive to prefer cheaper non-fossil energy. As that happens revenue and rebates diminish, but so does the average cost of goods, putting the entire population in a continuous "lower my carbon footprint" competition to stay below average and turn a profit. Obviously properly taxing the carbon footprint of imported goods would require either rough tariffs, or an international agreement on carbon tax rates.
Sure, but malware on the phone is a secondary problem - anyone that has to resort to those tactics is a relatively minor threat to your freedom.
Still, something that I'd be all for - absolutely no sense making it easy for people. Personally I rarely have a use for GPS, and keep location information turned off on my phone for exactly that reason.
Breakeven is actually the easier "theoretical" milestone to reach - ignition is more difficult as it has to take into account environmental heat losses so that the reaction can be self-sustaining. Paragraph two on your link.