Which seems to me why it would be eminently doable - it can be implemented as a far more streamlined replacement for benefits, rather than something set in place on top of benefits. Welfare, government pension plans, subsidized housing, and on and on - there's no need for it with a basic income system. If so desired it can even replace minimum wage... with the benefit to companies being offset by new corporate taxes to help hike the basic income further, and removing the distorting market influence of minimum wages. Your basic income *is* your minimum wage.
We've basically as a society already decided that we don't want people just starving in the streets. But this patchwork of programs we've built as a consequence, with their huge overheads, hurdles everyone has to jump through and gaps to fall between** is not the solution. Basic income is. And once you've got it then all of the debates between the left and right get much simpler - the left tries to raise the basic income at the cost of higher taxes on corporations and wealthy individuals, while the right tries to do the opposite.
**In my experience, the gaps in current systems are the most likely to hit the vulnerable. For example, a guy I know has long had trouble working because of some serious psychological issues, huge social anxiety problems among others. To get on benefits he has to be certified by a doctor. But because of his anxiety he's terrified of doctors; even when he can get himself to go he usually says as little as possible and plays everything down to get out of there as soon as possible and not have to answer questions. And doctors visits cost money (even where everyone is insured), which people who have trouble working generally lack. Which gives him even more excuse to give into his fear and not go. It's sad, I've seen him at times go hungry so that he could feed his kids, and at one point was living in a tent until it got crushed in a storm (with him in it).
We don't need this mess. Just give everyone a basic income. Sure, you'll need to have some variations, such as a credit for those with children, maybe something extra for those who get certified for long-term disability, etc. But *something* for everyone. We're not talking about ensuring everyone a life of luxury. We're just talking about enough to:
1) Pay for basic groceries (not going out to eat, nothing fancy) 2) Cover basic transportation (bus fare or operation of the cheapest junker on the market) 3) Keep a roof over one's head - either a single rented room for a single person, or a small shared apartment for two. 4) Pay for medical copays, basic clothing, and the other random expenses of life
Please. The ruble's collapse is all part of a glorious plan to provide the poor with a new source of heating fuel (worthless rubles). Would America ever do anything like that for its poor? No!
Muslims are supposed to pray toward Mecca, not "east". So they just need to know where they are in space, aim appropriately, and potentially have some angular momentum at times. That's not the tricky one. The tricky one is, what to do about fasting during Ramadan?;) My understanding is that Ramadan fasts may be omitted for a person who is traveling, and so I suspect they'd just define that as "travel".
Actually, NASA does have a detailed contingency plan for dealing with "rogue elements" in space: bind the subject's wrists and ankles with duct tape, tie them down with a bungee cord, and if needed, inject them with tranquilizers, all the while trying to calm them down verbally, explaining what you're doing and why you need to do it.
It sounds kind of funny that they'd take the time to make such a plan, but it was created in case an astronaut for some reason or another goes crazy while in orbit. It's also allowed for if an astronaut is trying to commit suicide.
You missed the point. It's not the 9th. It's either the 8th, 10th, or some number greater than 10. There's no logical definition that makes it the 9th apart from "historical".
Pluto is not the 9th planet by any measure. There's over a dozen bodies in hydrostatic equilibrium before it. If you don't count "planetary moons" you still have to count Ceres, there's no question that it's in hydrostatic equilibrium.
I don't use AdBlock and yet Forbes thinks I'm using it. So I can't read it.
But I can say, at least the infrared claim doesn't hold up. Wise ruled out Saturn-sized bodies out to 10k AU (based not on reflection but, due to the distances, more the internal heat they'd give off), but here we're talking about a body that's far smaller than Saturn and would have much less internal heat. The theoretical planet is 1/10th the mass of Saturn, and its IR from internal heat would be much less than that. And while one could argue that due to being closer its additional solar reflection would overcome that, I wouldn't be so sure. Neptune is 1,7x heavier than the theoretical planet yet still has a cross sectional area less than 18% that of Saturn. And you can't just scale down by that 1,7x to around 10% the cross sectional area of Saturn - it's probably much less because its colder (the reason why Neptune has a smaller radius than Uranus despite being heavier). And even more than what you'd get simply from cooling gases - at aphelion it could well be cold enough to chill liquid hydrogen out of its atmosphere into hydrogen seas. And that would make it dramatically smaller.
In short, if it's even remotely near aphelion, WISE could well have missed it. And elliptical-orbiting bodies spend much more of their time near aphelion than perihelion.
As for the required observations about KBOs, I don't know enough about the types of bodies and their orbits being referred to in the summary to know if we should already have seen them or not. But either way, we need *something* to explain the similar arguments of perihelion of the sednoids. It's hard enough just to explain how something with such a distant perihelion ended up in an elliptical orbit to begin with, let alone multiple such objects sharing similar arguments of perihelion.
While we don't have a large dataset out there, we do have two bodies of comparable size (10Me) in our solar system, Uranus (14,5 Me) and Neptune (17,1 Me), both of which have very dense atmospheres of hydrogen and helium. And the solar wind is weaker that far out. And when you look at the reasons why these bodies have atmospheres like this, the same logic should apply here: such big bodies tend to have strong protective magnetic fields because there's lots of internal energy to drive a dynamo, they have so much gravity that they can actually retain light gases (unlike Earth), etc. It's just to be expected.
Just take a page from their book and define the IAU. I suggest something like "A naval-gazing association dedicated to spending grant money to travel to remote locales to drink and make things up in the name of science."
I like Dara o'Brian's notion that racism is way better than astrology. You know, there's only 12 zodiac signs that people can have, but racists can easily break the world up into far more groups than that. Just bring in a racist daily to write the forecast for you. "It's going to be a good day for the Jews...."
The concept that dark matter wasn't normal matter wasn't arrived upon easily, it took until the 80s to really accept it. The thing is, even small objects still interact with EM radiation and such, and this has effects if you want to have enough of them to account for the missing mass. And these interactions just aren't observed, no matter what size bodies you assume. The closest you can get out of conventional matter is a hypothesis is for hypothetical objects called "macros", which is basically like tiny neutron stars.
Honestly, dark matter doesn't bother me at all. What's so weird about the concept of particles having little to no interaction with certain fields? Now dark energy, that's some evil sorcery there....
The whole "cleared the neighborhood" thing is based on a lie anyway. The vast majority of planets didn't clear their neighborhods. Jupiter**, and to a lesser extent Saturn, did. Mars' lack of influence on its neighborhood can be seen by how low of a percentage of asteroids are in a resonance with it.
Can we stop with the pretending that planets like Mars are responsible for sweeping their orbits clean? No models support this.
It's funny, but you see almost the exact same reason given by everyone interviewed who voted for the IAU definition - always a variant of "I don't want my daughter to have to memorize the names of 50 planets". As if that's even remotely any sort of scientific argument, as if we should say there's only 8 rivers in the world or 8 bones in the human body and all others are "dwarf rivers" and "dwarf bones" that aren't really rivers and bones, in order to make it easier for schoolkids.
They had their preconceived concept - they wanted a low, memorizeable number of planets - and tried to create a definition to fit it. And failed miserably at it. Now we've got a definition where a "Dwarf X" is not an X, despite the fact that in astronomy (and almost everywhere else) "Dwarf X" always denotes a type of X - dwarf stars, dwarf galaxies, etc. We've got a definition based on poorly defined concepts like "neighborhood". We've got a definition that arbitrarily excludes exoplanets from being planets, which is a terminology disaster. We have a definition that runs contrary to what people associate with the word "planet" - they expect "big round object floating through space around a star" - if it's pulled itself into a sphere, they think "planet", if it's lumpy then they think "not a planet".
We had a perfectly good dividing line: hydrostatic equilibrium. It's not just what the public expects the word to mean. Collapse into hydrostatic equilibrium produces altered minerals, releases of energy, fluids, and all sorts of things - they're the place you'd go to study planetary evolution, search for life, etc. Bodies that have not collapsed into hydrostatic equilibrium are where you'd go to study primordial materials, the origins of the solar system, etc. They're fundamentally different bodies.
And for that matter, what sort of nonsensical grouping is it that says that Mercury is more like Jupiter than it is Ceres? Want to pinch off some bodies from the list of planets? Go all the way. We have the inner planets, we have the gas giants, we have the ice giants.... IMHO I really like Stern's multi-classification approach. You have an adjective which describes the size and whether it's in hydrostatic equlibrium - say, superdwarf, dwarf, giant, supergiant, etc; you have a compositional term, such as terrestrial, gas/hydrogen, ice, etc - and you have an orbital term, such as "planet" (body that orbits around a star), "moon" (body that orbits around a planet"), and so forth. When describing a body, you can use as many or as few of the components as you need to.
(** Hell, if I really wanted to nitpick, I could point out that the definition requires planets orbit the sun. Jupiter orbits the Sun-Jupiter barycentre, which is not inside the sun. You can say "close enough", but where do you draw the cutoff line?)
1) The atmosphere would be pure - 100% pure helium. The only thing that could contaminate it would be hydrogen, so if it's cold enough for it to be fully condensed out (no hydrogen clouds/rain), then it'll be a monoatomic gas. No clouds.
2) The hydrogen seas would also be pure. There's almost nothing that can float in hydrogen - pretty much just foams gassed with helium, and that doesn't sound likely.
3) Weird nuclear properties: helium is a perfect neutron moderator - it never undergoes neutron capture. It can undergo high energy reactions, but at lower energies, any neutron in helium will become fully thermalized, which - at those temperatures - would make everything interact with it at a very high cross section. Since only helium would be in the atmosphere, that would most likely be 3He. So I would expect 3He depletion.
4) The day length would change when the hydrogen condensed out (like a ballerina pulling her arms in). I'm not sure off the top of my head of the effects of this mass redistribution on any orbital bodies, although I could picture, say, enhanced tidal heating due to the mass redistribution.
5) There's an awful lot of potential non-hydrogen liquids which could exist under the liquid hydrogen (or under the H2/He atmosphere near aphelion) - nitrogen, carbon monoxide, methane and other hydrocarbons, neon, even water. It all depends on the pressure and temperature curves, which one couldn't even begin to speculate on at this point. Most of the latter could potentially form eutectics, but hydrogen is not prone to forming eutectics, so would make its own distinct surface layer.
6) Lava flows of any type (silicate, cryolavas, whatever) would happen underneath the hydrogen ocean. Meaning pillowing. The boiloff of hydrogen could then expose these structures. What do pillow cryolavas formed under hydrogen look like? I haven't the foggiest.
7) Any hot lavas (such as silicates) erupting into liquid hydrogen might have unusual chemistry (metal hydrides and the like? extensive hydrocarbon formation? silanes, stabilized by the low temperatures?). This would then be left exposed on the surface when the hydrogen boils off. That surface could be a really bizarre place.
An interesting thought. Even at its perihelion (1100 AU), helium won't be getting cold enough to condense out. But hydrogen probably will, condensing to planetwide hydrogen seas. Meaning that - combined with its lower mass - its atmospheric density at perihelion on top of that is probably surprisingly low. However, at aphelion its only about 400AU. That's probably not cold enough to condense hydrogen. So every 15000 years it would go from having hydrogen oceans and low atmospheric pressure to an ice surface under crazy pressures.
What the heck do you call a planet like that?
Such a large planet would certainly have the internal heat for tectonics and volcanism. But I'm still so baffled from trying to picture what such a planet would be like just from that first aspect that I can't even begin to imagine what effect the latter would have on it.
Its perihelion is over 1100 AU. Sedna was discovered at 90AU. Wee bit of a difference there. Also, the degree of the solar system we've searched varies greatly in detection ability, some areas much better studied than others. It's estimated that we've only found about 1% of KBOs larger than 100km.
Assuming it exists, it orbits the sun, it is large enough to be round, and it's big enough it probably has "cleared its neighborhood"
It has as mentioned a semi-major axis of around 700AU. That's 23 times more than Neptune. It has a mass of about 10Me, or 58% of Neptune. Its Margot discriminant would be less than a tenth of Mars' (lowest in the solar system). Plus, it's highly elliptical (e=0.6), meaning it has a far broader neighborhood to clear (something not taken into account in the discriminant).
Hydrostatic equilibrium is part of the definition.
Planetary scientists wanted a definition based solely around hydrostatic equilibrium; the main group pushing for an orbital dynamics definition was astrophysicists. The original draft was based around hydrostatic equilibrium, so many of them left, content that they'd either get a hydrostatic equilibrium definition or no definition at all.
Not really. There's going to be some very powerful telescopes involved in survey work coming online over the course of the next decade that should dramatically increase our detection capability. My favorite is the LSST which should, for example, move from our current knowledge of about 1% of 100km+ KBOs to nearly 100%. And one can expect even more powerful telescopes in the decades after that.
Next decade, whenever anything is detected, we'll also have James Webb to get a better look at it.
Sorry, but many of us feel that the IAU's redefinition was a huge mistake. Including for example most of the New Horizons team. Heck, even when you press supporters of the concept of defining planets based on orbital characteristics rather than hydrostatic equilibrium you find that even most of them will admit that the definition as it stands is a mess and should be revisited. It's self-contradictory, vague, full of holes and creates more linguistic confusion than it solves.
It's worth adding that if we go by the IAU's definition, this thing - despite being 10 times bigger than the Earth - would almost certainly not be considered a planet, due to its distant elliptical orbit.
If - and I stress if - launch costs can be brought down to anywhere close to the propellant costs, space would be affordable to everyday people. If propellant was half of the total cost you might be looking at $10-50/kg. If a "passenger liner" version had about 50% of its mass comprised of passengers and the other 50% with structure and consumables, then you would be looking at ticket prices on the order of $1.5-7k.
The problem is, while it's certainly possible, we're nowhere even close to that. Fuel today isn't half the cost of a launch, it's 0,01 to 0,1 percent of the cost. If SpaceX can cut the cost of their launches from $5k/kg to $2k/kg or even $1k, then that would be great. But it's still not nearly enough for "general public" access to space. General public access to space is doable - there's no physics standing in the way, or any other sort of practicable barriers - but it's going to take not simply reusables. It will need a long, slow process of optimizing every aspect of rocket launches. And it'll require a steady buildup of launch rates along the way to pay for it. One's going to need a spike in customers at $1k/kg to pay for the scaleup that can bring costs down to $500/kg, another spike at $500/kg to bring it down to $250/kg, another spike at $250 to bring it down to $125... etc.
There's no fundamental reason why rockets can't be launched en masse, like aircraft; aircraft, too, were once toys for the rich and the military. But there's an awful lot of work to do before then, and a market to prove.
Yes, but that was not the contention I made. AS LONG AS the economics are not similar to that of airplanes
Which, according to the contention that I just made, if SpaceX is right then they will be like airplanes in the near-to-mid term. Pointing out that they're not like airplanes at this exact second is meaningless.
and frankly, without systems similar to Skylon, where you actually use the air in the atmosphere, you'll never get there
Nonsense. Propellant is cheap. The propellant cost to orbit is a couple dozen dollars per kilogram - 0,1% to 1% the cost of the launch. You don't need airbreathing engines. You need to not throw away your $70+m rocket after every flight. And, for that matter, not spend tens of millions of dollars spread out between making new tanks, reintegrating your recovered electronics and engines, extensively retesting the whole assembly (since it's basically a new untested rocket), retransporting it from the factory to the launch site, and all of the other pieces of overhead that make up much of that ~$70m+ cost to begin with.
And if you compare the first stage of spaceX with something like Adeline - which was what I compared - then you can definitely make an economic (better) case for the latter.
You can certainly try, but you've hardly even attempted that thusfar, just repeatedly asserting that returning the engines and avionics is somehow cheaper than getting a whole intact rocket back at the launch pad or on a barge ready to be hoisted back onto the launch pad.
but that doesn't change the fact that it IS economical more fruitful as of yet
Writing the word IS in capital letters doesn't change anything written above.
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Which seems to me why it would be eminently doable - it can be implemented as a far more streamlined replacement for benefits, rather than something set in place on top of benefits. Welfare, government pension plans, subsidized housing, and on and on - there's no need for it with a basic income system. If so desired it can even replace minimum wage... with the benefit to companies being offset by new corporate taxes to help hike the basic income further, and removing the distorting market influence of minimum wages. Your basic income *is* your minimum wage.
We've basically as a society already decided that we don't want people just starving in the streets. But this patchwork of programs we've built as a consequence, with their huge overheads, hurdles everyone has to jump through and gaps to fall between** is not the solution. Basic income is. And once you've got it then all of the debates between the left and right get much simpler - the left tries to raise the basic income at the cost of higher taxes on corporations and wealthy individuals, while the right tries to do the opposite.
**In my experience, the gaps in current systems are the most likely to hit the vulnerable. For example, a guy I know has long had trouble working because of some serious psychological issues, huge social anxiety problems among others. To get on benefits he has to be certified by a doctor. But because of his anxiety he's terrified of doctors; even when he can get himself to go he usually says as little as possible and plays everything down to get out of there as soon as possible and not have to answer questions. And doctors visits cost money (even where everyone is insured), which people who have trouble working generally lack. Which gives him even more excuse to give into his fear and not go. It's sad, I've seen him at times go hungry so that he could feed his kids, and at one point was living in a tent until it got crushed in a storm (with him in it).
We don't need this mess. Just give everyone a basic income. Sure, you'll need to have some variations, such as a credit for those with children, maybe something extra for those who get certified for long-term disability, etc. But *something* for everyone. We're not talking about ensuring everyone a life of luxury. We're just talking about enough to:
1) Pay for basic groceries (not going out to eat, nothing fancy)
2) Cover basic transportation (bus fare or operation of the cheapest junker on the market)
3) Keep a roof over one's head - either a single rented room for a single person, or a small shared apartment for two.
4) Pay for medical copays, basic clothing, and the other random expenses of life
Come on, are you saying that the Iranian space program is really a cover story for the development of, say, a super long-range anti-ship missile?
No, that's SpaceX. ;)
Please. The ruble's collapse is all part of a glorious plan to provide the poor with a new source of heating fuel (worthless rubles). Would America ever do anything like that for its poor? No!
Fadanaut?
Muslims are supposed to pray toward Mecca, not "east". So they just need to know where they are in space, aim appropriately, and potentially have some angular momentum at times. That's not the tricky one. The tricky one is, what to do about fasting during Ramadan? ;) My understanding is that Ramadan fasts may be omitted for a person who is traveling, and so I suspect they'd just define that as "travel".
Actually, NASA does have a detailed contingency plan for dealing with "rogue elements" in space: bind the subject's wrists and ankles with duct tape, tie them down with a bungee cord, and if needed, inject them with tranquilizers, all the while trying to calm them down verbally, explaining what you're doing and why you need to do it.
It sounds kind of funny that they'd take the time to make such a plan, but it was created in case an astronaut for some reason or another goes crazy while in orbit. It's also allowed for if an astronaut is trying to commit suicide.
You missed the point. It's not the 9th. It's either the 8th, 10th, or some number greater than 10. There's no logical definition that makes it the 9th apart from "historical".
I too support a high planet count.
Pluto is not the 9th planet by any measure. There's over a dozen bodies in hydrostatic equilibrium before it. If you don't count "planetary moons" you still have to count Ceres, there's no question that it's in hydrostatic equilibrium.
I don't use AdBlock and yet Forbes thinks I'm using it. So I can't read it.
But I can say, at least the infrared claim doesn't hold up. Wise ruled out Saturn-sized bodies out to 10k AU (based not on reflection but, due to the distances, more the internal heat they'd give off), but here we're talking about a body that's far smaller than Saturn and would have much less internal heat. The theoretical planet is 1/10th the mass of Saturn, and its IR from internal heat would be much less than that. And while one could argue that due to being closer its additional solar reflection would overcome that, I wouldn't be so sure. Neptune is 1,7x heavier than the theoretical planet yet still has a cross sectional area less than 18% that of Saturn. And you can't just scale down by that 1,7x to around 10% the cross sectional area of Saturn - it's probably much less because its colder (the reason why Neptune has a smaller radius than Uranus despite being heavier). And even more than what you'd get simply from cooling gases - at aphelion it could well be cold enough to chill liquid hydrogen out of its atmosphere into hydrogen seas. And that would make it dramatically smaller.
In short, if it's even remotely near aphelion, WISE could well have missed it. And elliptical-orbiting bodies spend much more of their time near aphelion than perihelion.
As for the required observations about KBOs, I don't know enough about the types of bodies and their orbits being referred to in the summary to know if we should already have seen them or not. But either way, we need *something* to explain the similar arguments of perihelion of the sednoids. It's hard enough just to explain how something with such a distant perihelion ended up in an elliptical orbit to begin with, let alone multiple such objects sharing similar arguments of perihelion.
While we don't have a large dataset out there, we do have two bodies of comparable size (10Me) in our solar system, Uranus (14,5 Me) and Neptune (17,1 Me), both of which have very dense atmospheres of hydrogen and helium. And the solar wind is weaker that far out. And when you look at the reasons why these bodies have atmospheres like this, the same logic should apply here: such big bodies tend to have strong protective magnetic fields because there's lots of internal energy to drive a dynamo, they have so much gravity that they can actually retain light gases (unlike Earth), etc. It's just to be expected.
Just take a page from their book and define the IAU. I suggest something like "A naval-gazing association dedicated to spending grant money to travel to remote locales to drink and make things up in the name of science."
I like Dara o'Brian's notion that racism is way better than astrology. You know, there's only 12 zodiac signs that people can have, but racists can easily break the world up into far more groups than that. Just bring in a racist daily to write the forecast for you. "It's going to be a good day for the Jews...."
Ugh.... can't believe I mixed those up... :P
The concept that dark matter wasn't normal matter wasn't arrived upon easily, it took until the 80s to really accept it. The thing is, even small objects still interact with EM radiation and such, and this has effects if you want to have enough of them to account for the missing mass. And these interactions just aren't observed, no matter what size bodies you assume. The closest you can get out of conventional matter is a hypothesis is for hypothetical objects called "macros", which is basically like tiny neutron stars.
Honestly, dark matter doesn't bother me at all. What's so weird about the concept of particles having little to no interaction with certain fields? Now dark energy, that's some evil sorcery there....
The whole "cleared the neighborhood" thing is based on a lie anyway. The vast majority of planets didn't clear their neighborhods. Jupiter**, and to a lesser extent Saturn, did. Mars' lack of influence on its neighborhood can be seen by how low of a percentage of asteroids are in a resonance with it.
Can we stop with the pretending that planets like Mars are responsible for sweeping their orbits clean? No models support this.
It's funny, but you see almost the exact same reason given by everyone interviewed who voted for the IAU definition - always a variant of "I don't want my daughter to have to memorize the names of 50 planets". As if that's even remotely any sort of scientific argument, as if we should say there's only 8 rivers in the world or 8 bones in the human body and all others are "dwarf rivers" and "dwarf bones" that aren't really rivers and bones, in order to make it easier for schoolkids.
They had their preconceived concept - they wanted a low, memorizeable number of planets - and tried to create a definition to fit it. And failed miserably at it. Now we've got a definition where a "Dwarf X" is not an X, despite the fact that in astronomy (and almost everywhere else) "Dwarf X" always denotes a type of X - dwarf stars, dwarf galaxies, etc. We've got a definition based on poorly defined concepts like "neighborhood". We've got a definition that arbitrarily excludes exoplanets from being planets, which is a terminology disaster. We have a definition that runs contrary to what people associate with the word "planet" - they expect "big round object floating through space around a star" - if it's pulled itself into a sphere, they think "planet", if it's lumpy then they think "not a planet".
We had a perfectly good dividing line: hydrostatic equilibrium. It's not just what the public expects the word to mean. Collapse into hydrostatic equilibrium produces altered minerals, releases of energy, fluids, and all sorts of things - they're the place you'd go to study planetary evolution, search for life, etc. Bodies that have not collapsed into hydrostatic equilibrium are where you'd go to study primordial materials, the origins of the solar system, etc. They're fundamentally different bodies.
And for that matter, what sort of nonsensical grouping is it that says that Mercury is more like Jupiter than it is Ceres? Want to pinch off some bodies from the list of planets? Go all the way. We have the inner planets, we have the gas giants, we have the ice giants.... IMHO I really like Stern's multi-classification approach. You have an adjective which describes the size and whether it's in hydrostatic equlibrium - say, superdwarf, dwarf, giant, supergiant, etc; you have a compositional term, such as terrestrial, gas/hydrogen, ice, etc - and you have an orbital term, such as "planet" (body that orbits around a star), "moon" (body that orbits around a planet"), and so forth. When describing a body, you can use as many or as few of the components as you need to.
(** Hell, if I really wanted to nitpick, I could point out that the definition requires planets orbit the sun. Jupiter orbits the Sun-Jupiter barycentre, which is not inside the sun. You can say "close enough", but where do you draw the cutoff line?)
More thoughts.
1) The atmosphere would be pure - 100% pure helium. The only thing that could contaminate it would be hydrogen, so if it's cold enough for it to be fully condensed out (no hydrogen clouds/rain), then it'll be a monoatomic gas. No clouds.
2) The hydrogen seas would also be pure. There's almost nothing that can float in hydrogen - pretty much just foams gassed with helium, and that doesn't sound likely.
3) Weird nuclear properties: helium is a perfect neutron moderator - it never undergoes neutron capture. It can undergo high energy reactions, but at lower energies, any neutron in helium will become fully thermalized, which - at those temperatures - would make everything interact with it at a very high cross section. Since only helium would be in the atmosphere, that would most likely be 3He. So I would expect 3He depletion.
4) The day length would change when the hydrogen condensed out (like a ballerina pulling her arms in). I'm not sure off the top of my head of the effects of this mass redistribution on any orbital bodies, although I could picture, say, enhanced tidal heating due to the mass redistribution.
5) There's an awful lot of potential non-hydrogen liquids which could exist under the liquid hydrogen (or under the H2/He atmosphere near aphelion) - nitrogen, carbon monoxide, methane and other hydrocarbons, neon, even water. It all depends on the pressure and temperature curves, which one couldn't even begin to speculate on at this point. Most of the latter could potentially form eutectics, but hydrogen is not prone to forming eutectics, so would make its own distinct surface layer.
6) Lava flows of any type (silicate, cryolavas, whatever) would happen underneath the hydrogen ocean. Meaning pillowing. The boiloff of hydrogen could then expose these structures. What do pillow cryolavas formed under hydrogen look like? I haven't the foggiest.
7) Any hot lavas (such as silicates) erupting into liquid hydrogen might have unusual chemistry (metal hydrides and the like? extensive hydrocarbon formation? silanes, stabilized by the low temperatures?). This would then be left exposed on the surface when the hydrogen boils off. That surface could be a really bizarre place.
Any other thoughts?
An interesting thought. Even at its perihelion (1100 AU), helium won't be getting cold enough to condense out. But hydrogen probably will, condensing to planetwide hydrogen seas. Meaning that - combined with its lower mass - its atmospheric density at perihelion on top of that is probably surprisingly low. However, at aphelion its only about 400AU. That's probably not cold enough to condense hydrogen. So every 15000 years it would go from having hydrogen oceans and low atmospheric pressure to an ice surface under crazy pressures.
What the heck do you call a planet like that?
Such a large planet would certainly have the internal heat for tectonics and volcanism. But I'm still so baffled from trying to picture what such a planet would be like just from that first aspect that I can't even begin to imagine what effect the latter would have on it.
Certainly a lot of energy in play here.
Its perihelion is over 1100 AU. Sedna was discovered at 90AU. Wee bit of a difference there. Also, the degree of the solar system we've searched varies greatly in detection ability, some areas much better studied than others. It's estimated that we've only found about 1% of KBOs larger than 100km.
It has as mentioned a semi-major axis of around 700AU. That's 23 times more than Neptune. It has a mass of about 10Me, or 58% of Neptune. Its Margot discriminant would be less than a tenth of Mars' (lowest in the solar system). Plus, it's highly elliptical (e=0.6), meaning it has a far broader neighborhood to clear (something not taken into account in the discriminant).
Planetary scientists wanted a definition based solely around hydrostatic equilibrium; the main group pushing for an orbital dynamics definition was astrophysicists. The original draft was based around hydrostatic equilibrium, so many of them left, content that they'd either get a hydrostatic equilibrium definition or no definition at all.
Not really. There's going to be some very powerful telescopes involved in survey work coming online over the course of the next decade that should dramatically increase our detection capability. My favorite is the LSST which should, for example, move from our current knowledge of about 1% of 100km+ KBOs to nearly 100%. And one can expect even more powerful telescopes in the decades after that.
Next decade, whenever anything is detected, we'll also have James Webb to get a better look at it.
Sorry, but many of us feel that the IAU's redefinition was a huge mistake. Including for example most of the New Horizons team. Heck, even when you press supporters of the concept of defining planets based on orbital characteristics rather than hydrostatic equilibrium you find that even most of them will admit that the definition as it stands is a mess and should be revisited. It's self-contradictory, vague, full of holes and creates more linguistic confusion than it solves.
It's worth adding that if we go by the IAU's definition, this thing - despite being 10 times bigger than the Earth - would almost certainly not be considered a planet, due to its distant elliptical orbit.
Yup... there's no ladder on the first stage!
If - and I stress if - launch costs can be brought down to anywhere close to the propellant costs, space would be affordable to everyday people. If propellant was half of the total cost you might be looking at $10-50/kg. If a "passenger liner" version had about 50% of its mass comprised of passengers and the other 50% with structure and consumables, then you would be looking at ticket prices on the order of $1.5-7k.
The problem is, while it's certainly possible, we're nowhere even close to that. Fuel today isn't half the cost of a launch, it's 0,01 to 0,1 percent of the cost. If SpaceX can cut the cost of their launches from $5k/kg to $2k/kg or even $1k, then that would be great. But it's still not nearly enough for "general public" access to space. General public access to space is doable - there's no physics standing in the way, or any other sort of practicable barriers - but it's going to take not simply reusables. It will need a long, slow process of optimizing every aspect of rocket launches. And it'll require a steady buildup of launch rates along the way to pay for it. One's going to need a spike in customers at $1k/kg to pay for the scaleup that can bring costs down to $500/kg, another spike at $500/kg to bring it down to $250/kg, another spike at $250 to bring it down to $125... etc.
There's no fundamental reason why rockets can't be launched en masse, like aircraft; aircraft, too, were once toys for the rich and the military. But there's an awful lot of work to do before then, and a market to prove.
Slow means big parachutes.
Big parachutes means heavy.
Heavy on a first stage means "no payload fraction to orbit".
A rocket explosion will not "burn out oxygen in an area"; rockets have their own oxidizer, in roughly stoichometric ratios with their fuel.
You cannot burn 100% of your propellant, the tanks do not completely drain.
Which, according to the contention that I just made, if SpaceX is right then they will be like airplanes in the near-to-mid term. Pointing out that they're not like airplanes at this exact second is meaningless.
and frankly, without systems similar to Skylon, where you actually use the air in the atmosphere, you'll never get there
Nonsense. Propellant is cheap. The propellant cost to orbit is a couple dozen dollars per kilogram - 0,1% to 1% the cost of the launch. You don't need airbreathing engines. You need to not throw away your $70+m rocket after every flight. And, for that matter, not spend tens of millions of dollars spread out between making new tanks, reintegrating your recovered electronics and engines, extensively retesting the whole assembly (since it's basically a new untested rocket), retransporting it from the factory to the launch site, and all of the other pieces of overhead that make up much of that ~$70m+ cost to begin with.
You can certainly try, but you've hardly even attempted that thusfar, just repeatedly asserting that returning the engines and avionics is somehow cheaper than getting a whole intact rocket back at the launch pad or on a barge ready to be hoisted back onto the launch pad.
Writing the word IS in capital letters doesn't change anything written above.