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That is simply not true. A post-World War III nuclear wasteland would be subject to attack and pillaging by roving human bands, whereas a deep space colony woul

That is simply not true. A post-World War III nuclear wasteland would be subject to attack and pillaging by roving human bands, whereas a deep space colony would not be. And energy transportation being lossy is not a deal breaker when you can generate massive amounts of energy out in space. Even if you lose 90% of it, 10% of an enormous number is still an enormous number.

gf000 2y ago
Did you account for the maintainance of any equipment out in space? Just because we can produce space junk faster doesn't make the rest any cheaper. Also, getting robbed is a luxury compared to not having air to breathe.
- ETH_start 2y ago
  It will get more affordable as the amount of infrastructure that is outside of Earth's gravity well — and any other steep gravity well — increases. The thing with the Starship is it allows us to expand that infrastructure rapidly, so we can soon have a sizable industrial base that can access low-gravity resources like asteroids and moon regolith.
ben_w 2y ago
Anywhere we can get to at the scale necessary to make significant power, there's not much stopping humans, or at least automated robots, from also going there to attack and pillage. -- The most habitable place in the solar system, outside of Earth, is Mars. Mars has 50% of the sunlight that Earth. Owing to the lower sunlight level, it is colder than Antarctica. The atmosphere is equivalent to taking ours, then systematically deleting every molecule that isn't carbon dioxide without replacing it with anything else. Owing to the combination of low partial pressure and low temperature, half the atmosphere condenses into the polar caps each Martian winter. The ground is more toxic than an actual, literal, superfund cleanup site. It is drier than the actual, literal Sahara. The lack of oxygen in the atmosphere means there's no ozone layer. The lack of ozone layer, the thin remaining atmosphere, and the lack of magnetosphere, means it's a high-radiation environment. PV there also gets regularly covered in dust. Our moon is even less hospitable, owing to no atmosphere at all and being tidally locked with Earth. Venus has an atmosphere so dense that it has gone beyond the critical point where gas and liquid cease to be distinguishable, so you could reasonably also describe it as an ocean. An ocean of 465°C supercritical CO2 in which lead occasionally condenses onto mountaintops. -- There's three currently achievable ways to transport power through space at scale. Optical, microwave, or kinetic. Optical is either a bunch of mirrors or a laser on the sending side, with a normal PV system on the receiving side. Usual caveats apply, Earth spins so it has a relative night, doesn't work through clouds, maximum power density before PV systems overheat etc. All EM systems, microwave and optical, share a constraint about focussing: minimal size of target depends on the size of the antenna and the wavelength used. Because microwaves are so much longer (no much freedom to choose a different wavelength as there's a limited atmospheric window), the normal suggestion for ground stations is a 10 km diameter receiving rectenna — that's contiguous, you don't get PV's advantage of being able to split it up. Kinetic currently means an RFG — launch it e.g. electromagnetically towards a similar coil on the ground that decelerates it to extract the energy. This is theoretically possible and would totally work, but to be clear: it's shooting a bullet into the barrel of another gun, and this is not something we have a lot of experience doing, certainly not at scale or for the purposes of power generation.
- ETH_start 2y ago
  There's little advantage in raiding a colony six months away if you then have to spend another six months returning with the stolen goods before you can even use them. Defending a settlement where the nearest potential aggressor is 50,000,000 km away is also a much easier task than defending one where the closest adversary is 1,000 km away. With respect to space-based solar power and EM power transmission: my first thought is that a 10-kilometre diameter receiving antenna is totally doable, especially considering how much energy can be sent from space to this one rectenna. Such a rectenna can also double as a PV station.
  - ben_w 2y ago
    > There's little advantage in raiding a colony six months away if you then have to spend another six months returning with the stolen goods before you can even use them. First: If it otherwise takes a year to build them, no difference. Second: If they're useful for you in-situ, they're useful for anyone else in-situ. Don't need to move an object to take control of it, for exactly the same reasons that the British didn't want to physically relocate the Suez Canal during the Suez crisis. > Defending a settlement where the nearest potential aggressor is 50,000,000 km away is also a much easier task than defending one where the closest adversary is 1,000 km away. False. Whether attacker or defender has advantage is not distance dependent, it's tech-dependent. Absolute stealth in space is only becomes impossible when you've already got something around a K1.5 civilisation in the vicinity, before that you can fairly easily hide passive IR signatures, deflect/absorb/otherwise minimise active EM scans, and the defender doesn't have the resources to saturate volume with gravity sensors to spot attacker's mass. Even with Starship, the current state of the art passive and active scanning of the entire planet Earth still has trouble — most recent news-worthy item is 2024 YR₄ which we know so little about that it could be anywhere from 40 to 90 metres. Even just painting that rock black would have meant it never got spotted because nobody wants to waste effort on active radar — and even if we did all start using active radar that too could be fairly easily defeated until it was too late, using even just the relatively primitive cross-section stealth reduction tech of the 1980s, because the scale of space itself makes radar less effective (radar bounces have a double inverse square). On the ground, you absolutely can saturate with CCTV even now, sufficient for banditry; military-quality stealth is much harder to defeat at scale. Close-in surveillance still available in space, but then you're back to a few kilometres, no distance advantage. Actually it's worse than that, because outside an atmosphere you can do a hard-gee deceleration in the last few seconds, but also you can just let go of some plastic ball bearings before decelerating and have your approach preceded by a deadly shower of hypervelocity radar-invisible shrapnel hitting whatever bits you didn't want to keep, e.g. the existing defence systems. Heck, if it's a military action, they can perform the attack years in advance and with almost total plausible deniability. > With respect to space-based solar power and EM power transmission: my first thought is that a 10-kilometre diameter receiving antenna is totally doable, especially considering how much energy can be sent from space to this one rectenna. Such a rectenna can also double as a PV station. Contiguous. And that's per ground station, not total, you'd need in the order of 250 for the default proposal just to reach current Terran electrical power usage levels, or 2000 if you add in non-electrical power usage levels. Name an existing artificial 10 km diameter contiguous surface. Closest I can think of is "an entire city", but even those are not usually contiguous. Well, touching, but not fully filled in, not fully wired up. Not even the concrete and tarmac, let alone the plumbing or wiring. If you're building stuff at this scale, the resources requirements for the ground stations alone, let alone the space elements, are enough to seriously consider a low-resistance high-current DC global planetary grid as an alternative, and then you just put PV plants in antipodal deserts and get 24/7 PV from ground mounted PV without storage. And the political problems which prevent that being built starting today and over the next five years, are trivial in comparison to the political issues from any significant space based beamed power system, even one which is sincerely and openly designed in a peaceful fashion (which is hard to prove). The overall power density isn't even much different than PV for a bunch of reasons, including safety, it just gives the possibility of getting powered in what is to our eyes darkness. If you could see RF, it would be like a time-averaged equivalent of a slightly cloudy day, 24/7 — lower peak, higher average, than PV in the same place. Consider the converse: if you were to design a system that is capable of having an arbitrarily high power density, it's no longer just a power source, it's a death ray. Other governments take a dim view of such things, and will likely cause aforementioned years-in-advance attacks with almost total plausible deniability. But even then, this is the wrong usage. Use power locally in space for things, don't beam it. If/when humanity gets to a full K2, suborning that much power generation capacity and pointing it at Earth doesn't look like a grape in a microwave, it looks like Alderaan every 14 days or so. We're not even politically ready for this kind of change, in much the same way and for many of the same reasons as ancient Athens would not have been politically ready for the sudden availability of Tsar Bomba during one of their fights with Sparta — but that only makes it fortunate that Starship is orders of magnitude too small to cause such an industrial change. For all the reasons I gave in the previous comment, if you consider Apollo to be analogous to a Kon-Tiki raft, Starship is a carrack, an orbital ring is a highway network, and even if we had one of those we're still orders of magnitude short of K1.

gf000 2y ago

Did you account for the maintainance of any equipment out in space? Just because we can produce space junk faster doesn't make the rest any cheaper. Also, getting robbed is a luxury compared to not having air to breathe.

ETH_start 2y ago
It will get more affordable as the amount of infrastructure that is outside of Earth's gravity well — and any other steep gravity well — increases. The thing with the Starship is it allows us to expand that infrastructure rapidly, so we can soon have a sizable industrial base that can access low-gravity resources like asteroids and moon regolith.

ben_w 2y ago

Anywhere we can get to at the scale necessary to make significant power, there's not much stopping humans, or at least automated robots, from also going there to attack and pillage. -- The most habitable place in the solar system, outside of Earth, is Mars. Mars has 50% of the sunlight that Earth. Owing to the lower sunlight level, it is colder than Antarctica. The atmosphere is equivalent to taking ours, then systematically deleting every molecule that isn't carbon dioxide without replacing it with anything else. Owing to the combination of low partial pressure and low temperature, half the atmosphere condenses into the polar caps each Martian winter. The ground is more toxic than an actual, literal, superfund cleanup site. It is drier than the actual, literal Sahara. The lack of oxygen in the atmosphere means there's no ozone layer. The lack of ozone layer, the thin remaining atmosphere, and the lack of magnetosphere, means it's a high-radiation environment. PV there also gets regularly covered in dust. Our moon is even less hospitable, owing to no atmosphere at all and being tidally locked with Earth. Venus has an atmosphere so dense that it has gone beyond the critical point where gas and liquid cease to be distinguishable, so you could reasonably also describe it as an ocean. An ocean of 465°C supercritical CO2 in which lead occasionally condenses onto mountaintops. -- There's three currently achievable ways to transport power through space at scale. Optical, microwave, or kinetic. Optical is either a bunch of mirrors or a laser on the sending side, with a normal PV system on the receiving side. Usual caveats apply, Earth spins so it has a relative night, doesn't work through clouds, maximum power density before PV systems overheat etc. All EM systems, microwave and optical, share a constraint about focussing: minimal size of target depends on the size of the antenna and the wavelength used. Because microwaves are so much longer (no much freedom to choose a different wavelength as there's a limited atmospheric window), the normal suggestion for ground stations is a 10 km diameter receiving rectenna — that's contiguous, you don't get PV's advantage of being able to split it up. Kinetic currently means an RFG — launch it e.g. electromagnetically towards a similar coil on the ground that decelerates it to extract the energy. This is theoretically possible and would totally work, but to be clear: it's shooting a bullet into the barrel of another gun, and this is not something we have a lot of experience doing, certainly not at scale or for the purposes of power generation.

ETH_start 2y ago
There's little advantage in raiding a colony six months away if you then have to spend another six months returning with the stolen goods before you can even use them. Defending a settlement where the nearest potential aggressor is 50,000,000 km away is also a much easier task than defending one where the closest adversary is 1,000 km away. With respect to space-based solar power and EM power transmission: my first thought is that a 10-kilometre diameter receiving antenna is totally doable, especially considering how much energy can be sent from space to this one rectenna. Such a rectenna can also double as a PV station.
- ben_w 2y ago
  > There's little advantage in raiding a colony six months away if you then have to spend another six months returning with the stolen goods before you can even use them. First: If it otherwise takes a year to build them, no difference. Second: If they're useful for you in-situ, they're useful for anyone else in-situ. Don't need to move an object to take control of it, for exactly the same reasons that the British didn't want to physically relocate the Suez Canal during the Suez crisis. > Defending a settlement where the nearest potential aggressor is 50,000,000 km away is also a much easier task than defending one where the closest adversary is 1,000 km away. False. Whether attacker or defender has advantage is not distance dependent, it's tech-dependent. Absolute stealth in space is only becomes impossible when you've already got something around a K1.5 civilisation in the vicinity, before that you can fairly easily hide passive IR signatures, deflect/absorb/otherwise minimise active EM scans, and the defender doesn't have the resources to saturate volume with gravity sensors to spot attacker's mass. Even with Starship, the current state of the art passive and active scanning of the entire planet Earth still has trouble — most recent news-worthy item is 2024 YR₄ which we know so little about that it could be anywhere from 40 to 90 metres. Even just painting that rock black would have meant it never got spotted because nobody wants to waste effort on active radar — and even if we did all start using active radar that too could be fairly easily defeated until it was too late, using even just the relatively primitive cross-section stealth reduction tech of the 1980s, because the scale of space itself makes radar less effective (radar bounces have a double inverse square). On the ground, you absolutely can saturate with CCTV even now, sufficient for banditry; military-quality stealth is much harder to defeat at scale. Close-in surveillance still available in space, but then you're back to a few kilometres, no distance advantage. Actually it's worse than that, because outside an atmosphere you can do a hard-gee deceleration in the last few seconds, but also you can just let go of some plastic ball bearings before decelerating and have your approach preceded by a deadly shower of hypervelocity radar-invisible shrapnel hitting whatever bits you didn't want to keep, e.g. the existing defence systems. Heck, if it's a military action, they can perform the attack years in advance and with almost total plausible deniability. > With respect to space-based solar power and EM power transmission: my first thought is that a 10-kilometre diameter receiving antenna is totally doable, especially considering how much energy can be sent from space to this one rectenna. Such a rectenna can also double as a PV station. Contiguous. And that's per ground station, not total, you'd need in the order of 250 for the default proposal just to reach current Terran electrical power usage levels, or 2000 if you add in non-electrical power usage levels. Name an existing artificial 10 km diameter contiguous surface. Closest I can think of is "an entire city", but even those are not usually contiguous. Well, touching, but not fully filled in, not fully wired up. Not even the concrete and tarmac, let alone the plumbing or wiring. If you're building stuff at this scale, the resources requirements for the ground stations alone, let alone the space elements, are enough to seriously consider a low-resistance high-current DC global planetary grid as an alternative, and then you just put PV plants in antipodal deserts and get 24/7 PV from ground mounted PV without storage. And the political problems which prevent that being built starting today and over the next five years, are trivial in comparison to the political issues from any significant space based beamed power system, even one which is sincerely and openly designed in a peaceful fashion (which is hard to prove). The overall power density isn't even much different than PV for a bunch of reasons, including safety, it just gives the possibility of getting powered in what is to our eyes darkness. If you could see RF, it would be like a time-averaged equivalent of a slightly cloudy day, 24/7 — lower peak, higher average, than PV in the same place. Consider the converse: if you were to design a system that is capable of having an arbitrarily high power density, it's no longer just a power source, it's a death ray. Other governments take a dim view of such things, and will likely cause aforementioned years-in-advance attacks with almost total plausible deniability. But even then, this is the wrong usage. Use power locally in space for things, don't beam it. If/when humanity gets to a full K2, suborning that much power generation capacity and pointing it at Earth doesn't look like a grape in a microwave, it looks like Alderaan every 14 days or so. We're not even politically ready for this kind of change, in much the same way and for many of the same reasons as ancient Athens would not have been politically ready for the sudden availability of Tsar Bomba during one of their fights with Sparta — but that only makes it fortunate that Starship is orders of magnitude too small to cause such an industrial change. For all the reasons I gave in the previous comment, if you consider Apollo to be analogous to a Kon-Tiki raft, Starship is a carrack, an orbital ring is a highway network, and even if we had one of those we're still orders of magnitude short of K1.