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Post by Enderminion on Apr 29, 2017 14:50:49 GMT
Magnetic fusion has been making strides, but I don't think it has reached break-even yet. And ICF has issues with power generation mechanisms and providing continuous power without having to store energy between pulses. again MIC fusion is a thing
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Post by SevenOfCarina on Apr 30, 2017 17:30:56 GMT
In-universe, every single industrial facility and fabricator capable of constructing and servicing a Hydrogen steamer is within the Hill spheres of either Earth, Luna, or Mars. Sensors aren't ubiquitous, but passive sensor technology is sufficiently advanced so as to render entire hill spheres monitorable with cheap, wide-field telescopes. Larger sensors typically assist in guiding interplanetary vessels, detecting small solar system bodies, monitoring mining colonies, orbital habs, industrial facilities, asteroid-diversion programmes, yada yada yada. Much larger, extremely powerful IR/visible light sensors do exist, but are mostly used for research purposes, and have a fairly narrowish field of view anyway. As for computer technology, I'll have to consult an expert on that, assuming, of course, that Moore's Law doesn't hold indefinitely. With regards to communications, how feasible are visible light or shorter wavelength laser communications stations and relay satellites, for data transfer at interplanetary distances, or even just from one end of a planetary Hill sphere to the other end? I don't really think millimetre/micrometer wavelength broadcasts will go out of usage, considering shorter wavelengths are blocked by a significant atmosphere. Also, is something like a wide-field laser communications array even possible? And as for killing Earth, I picked the 'giant impact' route, because, in my opinion at least, it was the most realistic. Also, do we have any data on stellar-mass bodies passing through the Oort cloud roughly two million years ago? Even a dwarf star that passed less than ~50,000 AU from the Sun should have knocked a significant number of icy Oort cloud bodies off their orbits and sent them hurtling into the inner system. If so, the impactor could be just one of many bodies on a collision course with the inner planets. Additionally, instead of the very first comet smacking into Earth, there would first be a significant increase in long-period comets entering the inner system, only then would the planets come under any significant bombardment. This would create a persistent fear that the next inbound comet would strike, say, Luna. Or Mars. If I'm not wrong, Earth should likely take multiple impacts before Mars or Luna get hit due to its mass. And as for your proposals, Asteroid deflection, Industrial accident :A single asteroid impact isn't going to cut it. Not enough velocity, not enough mass. By the time we're capable of shifting asteroids big enough to cause extinction events, we'd have a significant space presence, and it simply wouldn't make sense, economically, to move an asteroid for mining. As such, any early attempt at moving asteroids would likely be extremely closely monitored, and any unauthorised movement would nearly instantly be detected, considering the energies needed. Asteroid deflection, Terrorist act :This simply can't happen in-universe without detection. Like I stated, any burn that would significantly shift an asteroid's orbit would be detected very early, and considering the burn times needed, assuming reasonable jet powers and mass ratios, would quickly be put to a stop. Also, any asteroid that we can move in-universe simply won't do anything more than localised damage, which can easily be recovered from. Also, your burn beltward would also raise a lot of question marks, considering high levels of monitoring, and low belt populations. Catastrophic climate change, Accidentally caused :Climate change won't occur on timescales fast enough to be factor. A few meters of sea level rise would devastate coastal regions, wreck climate cycles, and shred ecosystems, but we should survive fairly unscathed, at least in the short-term. Also, catastrophic climate change would divert resources from the expansion spaceward, and would collapse local economies in multiple regions. It may be sufficient to cause an economic crisis though, and that is something that I'll need to research on. Nuclear war :Unless globalization reverses itself, countries become isolated, and international trade plummets, I really don't see this happening on a large scale. There's simply too much to gain by trading, so unless there's a radical shift in political ideologies, war between major nations simply won't be worth the effort. Nuclear exchanges might happen if wild card states are accounted for, but these nations have few warheads, and it wouldn't really provoke global nuclear war. Plus, if there was a cold war running in-universe, there would undoubtedly be warheads present in space, and on any surface colonies and mining units. Militarization of space is not really what I'm running for here. "Oops" plague :I, frankly, have no clue as to the feasibility of this. I should probably ask nerd1000 about this. I would guess, when large numbers of people are headed spaceward from multiple locations worldwide, long quarantines would become problematic to enforce. There would be a significant possibility of this plague escaping to space. Once there, it may or may not wreck the population faster than on Earth. Like I stated earlier, I have no idea. It may be workable, though, and could be a useful secondary factor. (i.e. Impact quakes cause a containment failure at a research facility, plague escapes). nerd1000 , opinions? Something happened :This doesn't really fit the theme of hard sci-fi, but is an interesting proposal nonetheless.
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Post by SevenOfCarina on Apr 30, 2017 17:36:31 GMT
Magnetic fusion has been making strides, but I don't think it has reached break-even yet. And ICF has issues with power generation mechanisms and providing continuous power without having to store energy between pulses. again MIC fusion is a thing MIC Fusion is a thing. But how hard is it to extract energy for power generation?
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Post by Enderminion on Apr 30, 2017 22:03:58 GMT
really hard, I though we were still talking about fusion DRIVES, sorrey SevenOfCarina
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Post by SevenOfCarina on May 1, 2017 7:27:40 GMT
really hard, I though we were still talking about fusion DRIVES, sorrey SevenOfCarina 🤔 I thought you were talking about this.
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Post by nerd1000 on May 1, 2017 7:57:21 GMT
"Oops" plague :I, frankly, have no clue as to the feasibility of this. I should probably ask nerd1000 about this. I would guess, when large numbers of people are headed spaceward from multiple locations worldwide, long quarantines would become problematic to enforce. There would be a significant possibility of this plague escaping to space. Once there, it may or may not wreck the population faster than on Earth. Like I stated earlier, I have no idea. It may be workable, though, and could be a useful secondary factor. (i.e. Impact quakes cause a containment failure at a research facility, plague escapes). nerd1000 , opinions? Is this plague man-made? Weaponized pathogens are a very different beast from natural ones: a weapon is usually designed for maximum lethality, whereas a natural disease is evolved for maximum fitness, which means that the host must survive long enough to pass the disease on to the next victim or the pathogen must have a method of transmission that works whether the host is living or dead. If you're making a weapon these traits are undesirable. A weaponized disease would ideally kill as many enemy troops as possible, then become harmless so that your troops can enter the area and mop up the survivors without wearing full NBC gear and spending days in quarantine afterwards. Most natural pathogens with very high lethality (e.g. Ebola) struggle to progress to a full epidemic because when an outbreak occurs they very quickly kill or incapacitate every susceptible person in the area- the disease is then unable to spread further. The same is likely to be true for bioweapons. The recent severe Ebola outbreaks in Africa were made possible by the local culture: It's traditional in the affected areas for people to touch and spend an extended period of time with the body of a dead family member. Ebola is transferred by body fluids, so this tradition allowed it to spread to new victims even after the original host was deceased. By contrast most successful global pathogens leave enough survivors for transmission to continue: a good example is Influenza, which is highly infectious (even before the start of symptoms, so you can spread the disease before you're incapacitated by sickness), fast mutating (so we cannot develop widespread resistance) and only rarely kills its hosts (so you can get re-infected by the next version). Another approach is that seen in Tuberculosis: most infected people are carriers that suffer no ill effects, so the disease can persist in the population even though individuals with symptoms eventually die. If you want the plague to be constrained to Earth you should give it a method of transmission that doesn't work aboard a spacecraft (like mosquitoes, water or the soil) or ensure that the symptoms become obvious before the person is highly infectious. Doing these things will of course inhibit its spread on Earth as well. I'd instead go for a disease that isn't apocalypse-level deadly but still bad enough to be the final nail in the coffin for a social system that's already on the edge of collapse: something like Spanish Flu (which killed upwards of 50 million people in 1918) would work well for finishing off Earth's civilization after something else put it under great strain. Spanish Flu is unusual because it primarily killed previously healthy adults: this happened because the virus was so immunogenic that the immune system of a strong, healthy adult overreacted. The massive inflammation made people very ill and susceptible to secondary infections like bacterial pneumonia that finished them off- this combined with the poor medical conditions caused by the first world war led to a mortality rate up to 20% (compared to the normal rate of around 0.1% for influenza). The victims of this kind of pathogen are of course the exact same people you'd be relying on to rebuild after a severe disaster of another kind... Another option is a disease that affects something else important, like staple crops.
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Post by The Astronomer on May 1, 2017 8:43:08 GMT
...Another option is a disease that affects something else important, like staple crops. Remember the Blight from Interstellar (12014) or the Black Rot from Orion's Arm (12000). This can be pretty scary.
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Post by nerd1000 on May 1, 2017 9:20:04 GMT
...Another option is a disease that affects something else important, like staple crops. Remember the Blight from Interstellar (12014) or the Black Rot from Orion's Arm (12000). This can be pretty scary. The Blight doesn't make much sense as described: according to the professor guy it doesn't need oxygen and can in fact survive on nitrogen. From a biochemist's perspective this is very silly. There are microbes that 'fix' nitrogen as ammonia, but this process is energetically expensive. Normally the energy needed comes from good old oxidative phosphorylation- anaerobic processes like fermentation are too inefficient (if you use fermentation as the energy source every N2 molecule fixed would cost 8 glucose molecules worth of energy, a price which is prohibitive).
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Post by The Astronomer on May 1, 2017 9:34:47 GMT
Remember the Blight from Interstellar (12014) or the Black Rot from Orion's Arm (12000). This can be pretty scary. The Blight doesn't make much sense as described: according to the professor guy it doesn't need oxygen and can in fact survive on nitrogen. From a biochemist's perspective this is very silly. There are microbes that 'fix' nitrogen as ammonia, but this process is energetically expensive. Normally the energy needed comes from good old oxidative phosphorylation- anaerobic processes like fermentation are too inefficient (if you use fermentation as the energy source every N2 molecule fixed would cost 8 glucose molecules worth of energy, a price which is prohibitive). Yes, I know, but how it attacks crops is what I'm pointing.
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Post by nerd1000 on May 1, 2017 9:50:37 GMT
The Blight doesn't make much sense as described: according to the professor guy it doesn't need oxygen and can in fact survive on nitrogen. From a biochemist's perspective this is very silly. There are microbes that 'fix' nitrogen as ammonia, but this process is energetically expensive. Normally the energy needed comes from good old oxidative phosphorylation- anaerobic processes like fermentation are too inefficient (if you use fermentation as the energy source every N2 molecule fixed would cost 8 glucose molecules worth of energy, a price which is prohibitive). Yes, I know, but how it attacks crops is what I'm pointing. Sorry, I sometimes get a bit funny about such things and start nitpicking. Professional hazard, perhaps.
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Post by The Astronomer on May 1, 2017 9:56:43 GMT
Yes, I know, but how it attacks crops is what I'm pointing. Sorry, I sometimes get a bit funny about such things and start nitpicking. Professional hazard, perhaps. ATTACK THE ENEMY CROPSThat thing aside, I think Interstellar's Blight, if possible, is probably not natural. Terrorist acts? Who knows! Orion's Arm's Black Rot is a nanotech-augmented GM fungus designed to destroy plants on the planet.
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Post by Enderminion on May 1, 2017 13:34:43 GMT
In the Lost Fleet franchise, Europa (moon) is still quarantined after the release of a bio-weapon, it killed to fast to spread to any other planets or moons, also the bio-weapon could survive in vacuum for however many thousand years later until the main stories
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Post by princesskibble on May 1, 2017 18:58:57 GMT
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Post by RiftandRend on May 8, 2017 19:40:12 GMT
If the earth needs to be uninhabitable then out of control nano-machines in a grey-goo style scenario would be a good solution. That would prevent unmanned craft from operating on the surface while a biological plague would not.
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Post by Enderminion on May 8, 2017 19:45:58 GMT
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