OOM Posted August 29, 2019 Share Posted August 29, 2019 (edited) The magnetic nozzle is not an engine. It can be connected to different reactors and get different types of engines, so disputes are useless. It can be a nuclear plasma rocket or tokamak. Edited August 29, 2019 by OOM Link to comment Share on other sites More sharing options...
KerikBalm Posted August 29, 2019 Share Posted August 29, 2019 Source? Link to comment Share on other sites More sharing options...
TiktaalikDreaming Posted August 29, 2019 Share Posted August 29, 2019 1 hour ago, ChrisSpace said: The "reaction chamber" is a bit small but you could be right. I think you're right. I think it's worth noting that the new devs seem like they're going through the projectrho list of stuff as source material. It's rapidly looking like kerbals do atomic rockets space program. Link to comment Share on other sites More sharing options...
KerikBalm Posted August 29, 2019 Share Posted August 29, 2019 Yea, they go to atomic rockets, ignore all the caveats and disclaimers and "maybe"s, and just add stuff in. Atomic rockets mentioned that maybe metallic hydrogen would be metastable... according to the most recent tests from a few months ago, its not... Yet the metallic hydrogen engines have been featured prominently in discussion about KSP2 from the devs and those in contact with the devs... Despite the fact that it was completely speculative, unlikely from the start, and now proven false. We now have an engine in KSP fueled by magic. Link to comment Share on other sites More sharing options...
mcwaffles2003 Posted August 29, 2019 Share Posted August 29, 2019 8 minutes ago, KerikBalm said: Yea, they go to atomic rockets, ignore all the caveats and disclaimers and "maybe"s, and just add stuff in. Atomic rockets mentioned that maybe metallic hydrogen would be metastable... according to the most recent tests from a few months ago, its not... Yet the metallic hydrogen engines have been featured prominently in discussion about KSP2 from the devs and those in contact with the devs... Despite the fact that it was completely speculative, unlikely from the start, and now proven false. We now have an engine in KSP fueled by magic. If its near endgame tech I hope we have to farm it from a gas giant as a means of incentivising space colonization Link to comment Share on other sites More sharing options...
TiktaalikDreaming Posted August 29, 2019 Share Posted August 29, 2019 3 minutes ago, KerikBalm said: Yea, they go to atomic rockets, ignore all the caveats and disclaimers and "maybe"s, and just add stuff in. Atomic rockets mentioned that maybe metallic hydrogen would be metastable... according to the most recent tests from a few months ago, its not... Yet the metallic hydrogen engines have been featured prominently in discussion about KSP2 from the devs and those in contact with the devs... Despite the fact that it was completely speculative, unlikely from the start, and now proven false. We now have an engine in KSP fueled by magic. Technically the latest results don't say it's not metastable so much as "oops, we lost it". But a metallic hydrogen rocket also ignores the issue that your rocket will melt unless made of unobtainium. And it's likely you're going to need a serious amount of fuel tank insulation even if it is meta stable, not too mention the fuel cost. And you would want to know exactly what can cause it to stop being meta stable. It would be all the issues of hydrogen peroxide but ramped up to stupid levels. Link to comment Share on other sites More sharing options...
KerikBalm Posted August 29, 2019 Share Posted August 29, 2019 6 minutes ago, TiktaalikDreaming said: Technically the latest results don't say it's not metastable so much as "oops, we lost it". I think you're referring to this, from 2017: https://www.sciencealert.com/the-world-s-only-metallic-hydrogen-sample-has-disappeared Whereas I am referring to this, from June 2019: https://www.sciencealert.com/french-scientists-believe-they-have-created-metallic-hydrogen https://arxiv.org/ftp/arxiv/papers/1906/1906.05634.pdf In which it states: Quote The continuous vibron frequency shift and the electronic band gap closure down to 0.5 eV, both linearly evolving with pressure, point to the stability of the insulator C2/c-24 phase up to the metallic transition. Upon pressure release, the metallic state transforms back to the C2/c-24 phase with almost no hysteresis, hence suggesting that the metallization proceeds through a structural transformation within the molecular solid, presumably to the Cmca-12 structure. ... The vibron frequency shift with pressure was reversibly observed upon pressure decrease (see Extended data Fig. 6) ... Upon pressure release, the infra-red transmission is discontinuously recovered and the pressure evolution of the IR absorbance of the hydrogen reversibly measured with pressure ( see Extended data figure 5). Note how all their observations that they used to convince people that the hydrogen had in fact become metallic reversed when they released pressure... they got it metallic at 427 GPa, and the reversals were evident at 415-410 GPa. They had cooled it down to 80K (-193 C), and even at over 400 GPa, it wasn't staying metallic upon pressure release. Its not metastable for any significant length of time. Experimentally confirmed. Of course, this is the first report, but I suspect other labs will confirm these observations in the near future. Link to comment Share on other sites More sharing options...
Bill Phil Posted August 29, 2019 Share Posted August 29, 2019 16 minutes ago, KerikBalm said: Yea, they go to atomic rockets, ignore all the caveats and disclaimers and "maybe"s, and just add stuff in. Atomic rockets mentioned that maybe metallic hydrogen would be metastable... according to the most recent tests from a few months ago, its not... Yet the metallic hydrogen engines have been featured prominently in discussion about KSP2 from the devs and those in contact with the devs... Despite the fact that it was completely speculative, unlikely from the start, and now proven false. We now have an engine in KSP fueled by magic. Well the definition of "magic" isn't exactly nailed down, but I would argue that since it's based on assumptions about metallic hydrogen's physical properties it isn't magic. Of course the physics should still be correct based on those assumptions - otherwise what's the point? But if that is the case then it isn't magic - it works given a set of assumptions. Just because those assumptions don't bear out in our world doesn't mean that it's magic. And of course this is still the very early stages of metallic hydrogen research - we're not even fully confident we've made any of the stuff, leading to enough wiggle room for there to remain a possibility, at least in my opinion. Not to mention KSP 2 development likely started some time ago, definitely before the more recent metallic hydrogen research (which came out like two months ago?). In all honesty KSP1 rockets ARE powered by magic - they consume some "liquidfuel" and "oxidizer" and somehow make thrust - but the physics of the nozzle design and so on doesn't work out, they're just the source of force vectors. In all honesty I'm glad we're at least getting actual fuel types - even though most of them seem to be speculative and/or potentially impossible. Link to comment Share on other sites More sharing options...
KerikBalm Posted August 29, 2019 Share Posted August 29, 2019 3 minutes ago, Bill Phil said: I would argue that since it's based on assumptions about metallic hydrogen's physical properties it isn't magic. But its based on assumptions made in the early 70's, whereas those assumptions in the last decade range from assuming you still needed 10-20 GPa of pressure (using the lower bound, this is 40,000x higher than the pressure of the shuttle's external tank), or stabilities on the order of a picosecond. The paper a couple months before the announcement of KSP 2 actually measured metallic hydrogen's properties at -193C (80 k), and they found that after becoming metallic at 427 GPa, it had reverted back to non-metallic by 410-415 GPa. So forget assumptions from the 1970's, we've recently gotten observations that show those assumptions were wrong (and the more recent assumptions of picosecond stability are compatible with the observations). They don't get a pass because 50 years ago they thought *maybe* it was possible, when modern science says no. Link to comment Share on other sites More sharing options...
DStaal Posted August 29, 2019 Share Posted August 29, 2019 2 hours ago, TiktaalikDreaming said: I think it's worth noting that the new devs seem like they're going through the projectrho list of stuff as source material. It's rapidly looking like kerbals do atomic rockets space program. Well, the Atomic Rockets site is designed to be a reference to currently known and theorized rocket designs - so any list of space engines is going to be entirely new, magic space dust, or a sublist of that site. Any realistic space program is likely to be an 'atomic rockets' space program. (And could we not have the metallic hydrogen debate here? There's already a thread for that.) Coming back to this image: This is the one we have the fewest guesses on at the moment. As a thought, could it be one of the magnetic confinement nozzles in use? But those circles at the edge seem a bit big for that yet - at least in comparison to the other images. I almost want to think there's some sort of thrust diverter or something surrounding the actual engine. Link to comment Share on other sites More sharing options...
kerbiloid Posted August 29, 2019 Share Posted August 29, 2019 11 minutes ago, DStaal said: Well, the Atomic Rockets site is designed to be a reference to currently known and theorized rocket designs - so any list of space engines is going to be entirely new, magic space dust, or a sublist of that site. Any realistic space program is likely to be an 'atomic rockets' space program. Theses of late XXI century student works. "Nyrath The Nearly Wise, and his significance in the human civilisation history." "Atomic Rockets. Anything beyond them?" Link to comment Share on other sites More sharing options...
Bill Phil Posted August 29, 2019 Share Posted August 29, 2019 1 hour ago, KerikBalm said: But its based on assumptions made in the early 70's, whereas those assumptions in the last decade range from assuming you still needed 10-20 GPa of pressure (using the lower bound, this is 40,000x higher than the pressure of the shuttle's external tank), or stabilities on the order of a picosecond. The paper a couple months before the announcement of KSP 2 actually measured metallic hydrogen's properties at -193C (80 k), and they found that after becoming metallic at 427 GPa, it had reverted back to non-metallic by 410-415 GPa. So forget assumptions from the 1970's, we've recently gotten observations that show those assumptions were wrong (and the more recent assumptions of picosecond stability are compatible with the observations). They don't get a pass because 50 years ago they thought *maybe* it was possible, when modern science says no. That doesn’t matter. If a material with the assumed properties existed its performance would be predictable. The name metallic hydrogen is most associated with such materials and has been making rounds in news sources. It’d be a recognizable name for players. We really have no idea what the properties are. We have some hypotheses but they’re based on the assumption that we actually made metallic hydrogen in the lab - which we don’t know for sure yet. Not only that but many materials exist which possess multiple solid forms - ice for example (though the structure of the water compound may be involved). This could be possible for metallic hydrogen as well - though it likely won’t be the case there is nonetheless a remote possibility. Modern science says “we haven’t studied the material enough to say anything, if we’ve seen it in the lab at all.” All that recent research found was that they lost a specific property of hydrogen when they released the pressure - that property may or not be a property of metallic hydrogen. Link to comment Share on other sites More sharing options...
SpaceFace545 Posted August 29, 2019 Share Posted August 29, 2019 On 8/24/2019 at 12:03 PM, GoldForest said: First era - Chemical rockets Second era - Fission engines - Orion Drive as well as Nuclear propulsion engines Third Era - Fusion Engines and Magnetic Engines Fourth Era - Project Daedalus This is how I see it going. Fifth Era - Krepstien Link to comment Share on other sites More sharing options...
KerikBalm Posted August 29, 2019 Share Posted August 29, 2019 (edited) 49 minutes ago, Bill Phil said: That doesn’t matter. If a material with the assumed properties existed its performance would be predictable. That doesn't change the fact that there's no scientific back to such a material existing. I can invent any set of properties to give a material, and then make an engine and say that this how an engine would work if a material with my specified properties existed... it would still be fantasy. Quote Not only that but many materials exist which possess multiple solid forms - ice for example (though the structure of the water compound may be involved). This could be possible for metallic hydrogen as well - though it likely won’t be the case there is nonetheless a remote possibility. #1) There are multiple solid forms of Hydrogen as well. I'm guessing that's what the reference to the " C2/c-24 phase " prior to the metallic transition refers to. Just as there are multiple high pressure forms of H2O, there are various high pressure forms of many materials. Almost none are meta-stable, diamond is cited as an example, but I'll again quote: https://physics.stackexchange.com/questions/307832/how-likely-is-it-that-metallic-hydrogen-is-metastable-at-atmospheric-pressure Quote I'm not aware of any modern studies that predict solid metallic hydrogen to be stable. In general, the metastable recovery of high-pressure phases all the way back down to atmospheric pressure is very rare. The most well known exception is the graphite-to-diamond phase transition, but in that case the energy difference between those two phases is only about 0.003 eV per atom. Don't know offhand what the energy difference per atom between hydrogen gas at one atmosphere and solid metallic hydrogen is, but you can be sure that it is enormous by comparison. Not saying that metastable metallic hydrogen is impossible, but it certainly would be counter to all expectations based on past experience with high-pressure phases of various materials. (Side Note: I work in high-pressure physics and the creation of solid metallic hydrogen has long been the "Holy Grail" of the high-pressure community. This is not the first time that someone has claimed to have created solid metallic hydrogen by static compression, and the claim is currently getting a lot of scrutiny by others in the high pressure community. BTW, fluid metallic hydrogen has been created in the laboratory using reverberating shock waves. ) This is nothing but a fantasy engine. * note: that answer came before the French groups 2017 and 2019 results, which do seem to demonstrate metallic hydrogen, but I await independent confirmation Edited August 29, 2019 by KerikBalm Link to comment Share on other sites More sharing options...
TBenz Posted August 29, 2019 Share Posted August 29, 2019 4 hours ago, KerikBalm said: Yea, they go to atomic rockets, ignore all the caveats and disclaimers and "maybe"s, and just add stuff in. Atomic rockets mentioned that maybe metallic hydrogen would be metastable... according to the most recent tests from a few months ago, its not... Yet the metallic hydrogen engines have been featured prominently in discussion about KSP2 from the devs and those in contact with the devs... Despite the fact that it was completely speculative, unlikely from the start, and now proven false. We now have an engine in KSP fueled by magic. A major departure from the completely non-magical "liquid fuel" we had before that worked efficiently and universally across practically all engines, from bipropellant rockets, to air breathing jet engines, to a nuclear thermal rocket. Link to comment Share on other sites More sharing options...
vossiewulf Posted August 29, 2019 Share Posted August 29, 2019 3 hours ago, TBenz said: A major departure from the completely non-magical "liquid fuel" we had before that worked efficiently and universally across practically all engines, from bipropellant rockets, to air breathing jet engines, to a nuclear thermal rocket. Link to comment Share on other sites More sharing options...
KerikBalm Posted August 30, 2019 Share Posted August 30, 2019 18 hours ago, TBenz said: A major departure from the completely non-magical "liquid fuel" we had before that worked efficiently and universally across practically all engines, from bipropellant rockets, to air breathing jet engines, to a nuclear thermal rocket. Kerosene would and does work for Bipropellant rockets and jet engines - it wouldn't work in an NTR though. Liquid hydrogen would work very well (with no changes, whereas kerosene mixtures may be slightly optimized for each application) with bipropellant rockets, jet engines, and NTRs. So far we've only got SABRE engines (sort of) as an example of a H2 powered jet engine, to my knowledge. There's no reason it won't work. Its simplified, but not unrealistic (you could build all your engines to use lH2). In that case its just unrealistic that they don't model the bulk of lH2 tanks, and boiloff Link to comment Share on other sites More sharing options...
Standecco Posted August 30, 2019 Share Posted August 30, 2019 (edited) On 8/29/2019 at 1:59 PM, KerikBalm said: Note how all their observations that they used to convince people that the hydrogen had in fact become metallic reversed when they released pressure... they got it metallic at 427 GPa, and the reversals were evident at 415-410 GPa. They had cooled it down to 80K (-193 C), and even at over 400 GPa, it wasn't staying metallic upon pressure release. Its not metastable for any significant length of time. Experimentally confirmed. Of course, this is the first report, but I suspect other labs will confirm these observations in the near future. The metallic form they obtained isn't the only one possible, as stated in the paper: In the last paragraph, they explain that the metallic form they had obtained wasn't monoatomic hydrogen, which is a different matter. Quote Following the DMC calculation, the atomic metal should be observed above 447 GPa, but its characterization is beyond the capability of the infrared approach used. All metals are actually monoatomic, since you can't find a molecule in there, so the hydrogen they obtained wasn't a proper metal. That said, I don't really believe in this mythical metastable metallic hydrogen, but this isn't definitive proof. The paper itself talks about its possible uses, so the authors aren't ruling it out either. Edited August 30, 2019 by Standecco Link to comment Share on other sites More sharing options...
DStaal Posted August 31, 2019 Share Posted August 31, 2019 As far as this discussion is concerned - this engine has been confirmed to be a metallic hydrogen engine at this time. (The engine on the left.) Whether that's a good thing or not that's another discussion. The point of this thread is to identify what engines are in the game, not speculate on what engines *should* be in the game. Link to comment Share on other sites More sharing options...
KerikBalm Posted August 31, 2019 Share Posted August 31, 2019 10 hours ago, Standecco said: The metallic form they obtained isn't the only one possible, as stated in the paper: In the last paragraph, they explain that the metallic form they had obtained wasn't monoatomic hydrogen, which is a different matter. fair enough, that's just enough to push it from disproven science back to speculative science 8 hours ago, DStaal said: As far as this discussion is concerned - this engine has been confirmed to be a metallic hydrogen engine at this time. ... Whether that's a good thing or not that's another discussion. The point of this thread is to identify what engines are in the game, not speculate on what engines *should* be in the game. Yea, we shouldn't diverge too much as a result of comments about Atomic Rockets as the source. But given that its the source for a lot of this, I expect that the other engines are some sort of magnetic confinement, inertial confinement, and inertial-magnetic confinement. If there's a drive with epstein drive like qualities, it may be antimatter, or antimatter "catalyzed" fusion if they want to be a tad bit more realistic. Link to comment Share on other sites More sharing options...
magnemoe Posted September 1, 2019 Share Posted September 1, 2019 On 8/29/2019 at 1:43 PM, mcwaffles2003 said: If its near endgame tech I hope we have to farm it from a gas giant as a means of incentivising space colonization Its look like its mid tire, Orion make sense at mid tire a bit above LV-N, metalic hydrogen makes sense as an idiotic expensive high tire high trust 2xLV-N ISP fuel. The stuff you use on your dropships, at the end of an interstellar voyage. No the fuel on the SR71 was not more expensive than old whiskey, the oil was. Still cornflakes is more expensive as food at ISS than Russian caviar as the later has more calories/Kg, Interstellar this effect expands this some order of magnitudes. Link to comment Share on other sites More sharing options...
TiktaalikDreaming Posted September 1, 2019 Share Posted September 1, 2019 On 8/29/2019 at 9:43 PM, mcwaffles2003 said: If its near endgame tech I hope we have to farm it from a gas giant as a means of incentivising space colonization I haven't done the actual maths, but it seems very unlikely metallic hydrogen engines provide enough delta v to mine metallic hydrogen from gas giants. Once you're down at metallic hydrogen depths, you need something better than that to get out again. Ignoring the issues with developing pressure vessels to withstand the environment. Ifff it's metastable that's fine eventually, but the gas giant cores aren't relying on that. So, you need a propulsion system more capable than mythical metallic hydrogen drives to get out again, simply because your energy source is the compression that caused it, and you'd be experiencing it. The distances and gravity make a pipe or line unworkable for the same reasons space elevators are hard to build, but this would be much much worse. Trips for even sensor dones to gas giant cores are one way without some super science or magic. Link to comment Share on other sites More sharing options...
KeranoKerman Posted September 1, 2019 Share Posted September 1, 2019 (edited) On 8/29/2019 at 9:24 AM, TBenz said: A major departure from the completely non-magical "liquid fuel" we had before that worked efficiently and universally across practically all engines, from bipropellant rockets, to air breathing jet engines, to a nuclear thermal rocket. Lf could be liquid hydrogen, and Oxidizer ClF3. I’m fine if metallic hydrogen gets in or not. If it does though, it should have extremely expensive manufacturing plants. To add them to colonies, you’d need a massive rocket. edit: I hope ClF3 gets in compared to Oxidizer. Edited September 1, 2019 by KeranoKerman Wish for KSP 2, Added Links, Clarification Link to comment Share on other sites More sharing options...
Xd the great Posted September 2, 2019 Share Posted September 2, 2019 1 hour ago, KeranoKerman said: Lf could be liquid hydrogen, and Oxidizer ClF3. I’m fine if metallic hydrogen gets in or not. If it does though, it should have extremely expensive manufacturing plants. To add them to colonies, you’d need a massive rocket. edit: I hope ClF3 gets in compared to Oxidizer. ClF3 WILL kill of every kerbal that breathes in its vicinity, or stand in its vicinity. It will also corrode every building in its sight. No. Please don't add it as a stock fuel. But I am totally fine with it as a mod. Link to comment Share on other sites More sharing options...
TiktaalikDreaming Posted September 2, 2019 Share Posted September 2, 2019 What would be good is more detail on propellants, with negative consequences of sorts. Like start with diesel oil and rfna, and so on. That would complicate things. Even if they're abstracted, there's a huge difference in the craft for hydrogen vs kerosene fuels. And so on Link to comment Share on other sites More sharing options...
Recommended Posts