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How so many educated, intelligent people seem to think that we (as a species, or even as Americans) are so resource-poor that “space exploration” and “improving
by allenrb 5y ago
How so many educated, intelligent people seem to think that we (as a species, or even as Americans) are so resource-poor that “space exploration” and “improving the earth” yield an either/or decision absolutely mystifies me.
You want to free up resources for either one? Start with global military spending and the financial sector. Both have their place and both have grown far beyond it.
- lumost 5y agoThe economy isn’t zero sum. Particularly in this case where aerospace innovation has been largely funded by the military for the last 80 years. Rocket engines, hypersonic vehicles, and orbital rockets have a dual use for missile technology ( both conventional and nuclear )
- dchichkov 5y agoUsing these resources to improve chemical flamethrowers is sub-optimal. A dead end. Nuclear fusion is a more likely answer to spaceflight and Earth's clean energy problem. It likely should be the priority.
- perl4ever 5y ago>Nuclear fusion is a more likely answer to spaceflight and Earth's clean energy problem. Considering we don't even have fission rockets or airplanes in normal use, making a fusion powerplant that is light enough to get off the ground seems very far fetched. Even if we eventually use fusion for travel beyond earth orbit, I'd bet chemical rockets would still be in use. Don't we already have thrusters that are useful in space, but completely unable to support themselves against 1G and so they can't lift off from the ground? I feel like I've read something that said fusion power would fall in the same category.
- dmoy 5y ago> Don't we already have thrusters that are useful in space, but completely unable to support themselves against 1G and so they can't lift off from the ground? Yes. For example ion thrusters have specific impulse that is like an order of magnitude or two (or three?) better than chemical rockets, but they can't lift anything out of the atmosphere. > I feel like I've read something that said fusion power would fall in the same category. Sorry I have no idea about that.
- barbacoa 5y agoFor those interested: As absurd as it sounds nuclear powered aircraft engines are a thing.[1] They have also been proposed for spacecraft, Scott Manley does a great video talking about nuclear rocket engines[2]. [1]https://en.wikipedia.org/wiki/Project_Pluto https://en.wikipedia.org/wiki/Project_Pluto [2]https://www.youtube.com/watch?v=cvZjhWE-3zM https://www.youtube.com/watch?v=cvZjhWE-3zM
- vimacs2 5y agoI flirted with the idea of using supersized nuclear powered aircraft as the terrestrial version of the Aldrin cycler[1] concept. Basically, these things would be designed to never land but instead run in circular paths between continents with a fleet of onboard craft and hangers that will exchange cargo and passengers instead. They will be designed from the ground up to be maintanable and refuelable under constant operation (not a particularly difficult goal for a nuclear powered craft). Safety is a very valid concern for any supersized airborne vehicle but especially a nuclear powered one! However, this is one department where scale in itself brings it's own benefits. The volume increases faster than the surface area so you could have a hull far thicker than that of many naval ships while still having a truly vast interior volume. Not needing to ever land also reduces avenues for sabatoge and presumably the craft's interior itself would be heavily compartmentalized. You can also optimise your hull to deal with a narrow air pressure range which you cannot do with normal craft which need to be able to handle a wide range from ground level to the stratospheric. https://en.wikipedia.org/wiki/Mars_cycler https://en.wikipedia.org/wiki/Mars_cycler
- deleted 5y ago[deleted]
- mr_toad 5y agoDFDs seem promising, but are far from producing 1G of thrust. https://en.m.wikipedia.org/wiki/Direct_Fusion_Drive https://en.m.wikipedia.org/wiki/Direct_Fusion_Drive
- vimacs2 5y agoEven if we pretended that it's rational to hedge all your bets on not only having a working fusion reacter in the near term future but having the capability to miniturise it to a degree where it could be used as an engine for a launch vehicle, you would still be dead wrong. Fusion still shares the same fundumental problem that chemical rockets or even more advanced options like blackhole or antimatter drives face - the rocket equation. We need to use near term reusable launch vehicles like the Starship to help set up the required launch assist structures that would make genuine mass transit of people and cargo into orbit possible. Things like skyhooks, lofstroom loops, and eventually orbital rings that would allow people to ride trains or cable cars from an earth city straight into orbit for the same price range as intercity travel today. Needless to say, that is not going to happen until there is enough of an industry up there to justify the large upfront costs of such megaprojects (especially the orbital ring) so the Starship is our best near term hope of getting us up to that point. Note that none of these projects require advanced materials or new technologies (as opposed to the space elevator that is likely to remain science fiction when it comes to dealing with a body with the gravity well of earth anyway), they're just massive engineering projects.
- dchichkov 5y agoThe difference between chemical/fission and fusion are orders of magnitude. It is <10km/s for chemical/fission. And 1000km/s for fusion: "Today’s best chemical rockets produce propellant exhaust velocities up to 4.5 km/s. Fission (nuclear thermal) rocket engines could roughly double that, to about 8.5 km/s. A working nuclear fusion core producing thrust through direct exhaust of hot plasma, could readily generate up to ~1000 km/s exhaust velocities" - https://link.springer.com/article/10.1007/s10894-015-0034-1 https://link.springer.com/article/10.1007/s10894-015-0034-1 Likely necessary for advanced space flight. Likely necessary to allow for "clean energy" on earth. Unlike advances to flamethrowers.
- vimacs2 5y agoHaving high exhaust velocities does not mean you will have the high thrusts required to get yourself out of the earth's atmosphere. Most current proposals for Nuclear Fusion powered ships involve an exhaust that is orders of magnitude more diffuse than that of chemical rockets. They only come into their own once they are already in space or in orbit which returns us to the problem that we need to have launch assist infrastructure that can deal with that first step without resorting to those "flamethrowers" as you call them. It's also not true at all that fusion is necessary to allow for clean energy (even ignoring that many of the near term fusion reactor designs still need to have radiation shielding to deal with dangerous neutron emissions). We could use a combination of renewable sources and nuclear fission to deal with the energy crisis now and then utilise fusion once it's finally matured to the point of usefulness. Indeed, we could use that orbital infrastructure to help construct a planetary cloud of solar collectors that can operate 24/7 and beam that energy down via microwave rectiner technology that is already capable of achieving greater than 85% energy conversion (keep in mind that we lose far more energy simply from the diffusion of sunlight through the atmosphere). This approach not only can power the earth but any off earth colonisation prospects with line of sight with our planetary cloud - without needing to haul the likely massive early generation fusion reactors. Neither is fusion necessary for advanced space travel. It would be very useful but chiefly for travel to under-developed sectors of the solar system. solar reflectors scaled up enough can be used to speed up and slow down entire fleets of ships with far higher potential top speeds than even antimatter drives permit (since there is no requirement to have onboard propellant). They also double as handy point defense systems for dealing with both debris and ships that are attempting to turn themselves into relativistic kill missiles - remember that there is no such thing as an unarmed space ship, they are all potential weapons of mass destruction, especially once we reach the state where we have fusion drive powered ones.
- trhway 5y agonuclear engines, even just the fission, are the future for the space. The thing is you'd never be able to launch them on Earth. So, the first thing is to get enough stuff into space and establish an assembly/test platform there, Moon probably. With Starship the Moon becomes just a 3 day trip for 100ton cargo while burning less than $10M of fuel. >Using these resources to improve chemical flamethrowers is sub-optimal. A dead end. Earth launch future is large rail gun (somewhere like Bolivia) as a first stage booster. Requires a bit of political will, international cooperation and a few billions. Unfortunately the 1st and 2nd aren't coming soon, so the "chemical flamethrowers" for now.
- deleted 5y ago[deleted]
- spfzero 5y agoLook at the numbers. SpaceX is doing it’s thing for a few billion a year. That’s chump change compared to the money being spent on, let’s say professional basketball. Not picking on basketball it’s my favorite spectator sport. But saying, if you want to find something less worthy than “improving the earth”, you have about a hundred better targets than space exploration.
- h0l0cube 5y ago> SpaceX is doing it’s thing for a few billion a year One can project from SpaceX's launch history that as the commercialization of space intensifies, this figure is going to continue to grow exponentially https://www.spacexstats.xyz/#launchhistory-per-year https://www.spacexstats.xyz/#launchhistory-per-year
- midasuni 5y agoGood. Maybe it will eventually reach the amount spent on causing brain damage to teenagers.
- h0l0cube 5y agoFor the amount of downvotes I received, is this the best rebuttal anybody can come up with?
- throwaway316943 5y agoI think it sums it up nicely. The fact that a company makes a lot of money isn’t an argument against them and we spend a lot of money on many nonsensical things so spending more on something that drives technological advancement is a good thing.
- h0l0cube 5y ago> The fact that a company makes a lot of money isn’t an argument against them I wasn't making an argument against companies making a lot of money. I was merely pointing out that the commercialization will be sinking capital investment far greater than just 2 billion, contrary to the poster's claim. I don't speak of the counterfactual, i.e., where that excess money would go otherwise, but I do share the OP's lament that we should be trying to fix problems on Earth. If Space tech can help in some way, I'm all for that. > spending more on something that drives technological advancement is a good thing Technologies are amoral. Whether or not the advancement or deployment of any particular technology is a 'good thing' is a matter of subjectivity.
- cryptonector 5y agoMalthusians exist. They think we're running out of oil, soil and arable land, fresh water, and... just about everything. The logic is that since population growth is exponential, we really could run out of resources. And... that's both totally correct and totally wrong. Totally correct: because yeah, duh, if we had 1 trillion people... Totally wrong: because in fact the arc of evolution of fertility rates, population pyramids, and total population is bent and bending more and we will in fact be facing a shrinking world population soon. Meanwhile we have more oil and gas reserves now than ever. We're not running out of anything, not really. But the malthusians want to reduce population by 16x. They really do. It's crazy. Now, to answer your question... Substitute any topic into "how is it that so many educated, intelligent people seem to think that we...". The answer is pretty simple: we each don't know everything, in fact we know very little (and about many many things nothing really), and we are very (extremely!) susceptible to peer pressure, and we like to go with the flow, and we accept authority blindly where we know little, and so on. It's a real problem. We just don't teach people how to think about what they know little about. Epistemology is hard enough, but we need people to do more than reason about what they know and how they know it and what they might not know and all that. We need people to have an idea of how to think about the stuff they know little about that they don't even want to know about -- stuff that -no matter how little they care for the details of- is super topical and where getting the answers collectively wrong could be disastrous.
- KronisLV 5y ago> But the malthusians want to reduce population by 16x This seems pretty extreme, but thank you for bringing the concept of Malthusianism ( https://en.wikipedia.org/wiki/Malthusianism https://en.wikipedia.org/wiki/Malthusianism ) to my attention. While i'm not convinced that it's likely to be the end of humanity (but rather the results of thousands of compounding factors), the irresponsibility in regards to unrestrained consumerism is something that i see every day, and there is certainly some merit to those arguments in my eyes because of this. > The answer is pretty simple: we each don't know everything, in fact we know very little (and about many many things nothing really), and we are very (extremely!) susceptible to peer pressure, and we like to go with the flow, and we accept authority blindly where we know little, and so on. This, however, i'm not entirely sure about. Short of militant disregard for climate change or even the idea that human actions are capable of changing it in the first place, the viewpoints that i've personally seen expressed are more in the direction of feeling powerless and somewhat depressed about the state of things. Instead of outright ignorance, most of the people that i've talked with believe that the governments have largely failed them and the mechanisms of representation that should be in place are only so as far as looks are concerned. For example, lobbying and corporate interests are prioritized, as well as industry development is prioritized over sustainability. In the end, it feels like maximizing profit margins takes precedence over sustainable progress and long term advancement. Edit: Climate change and all that is just one example, but the fact that many feel powerless even if they aware of what's going on stands for other things as well. And most of those people that i've talked with have felt like there's little to nothing that they can individually do, seeing as a significant portion of the society is more than happy to live a hedonistic lifestyle that's rooted in consumption. That doesn't mean that we need to live in some dystopian nightmare either, but i'd argue that it's definitely a worthy goal to make the environment thrive first and to focus on a more utilitarian way of life - meat dishes as something to enjoy rather than to have with every meal, a new phone every 5 years instead of every single year, energy efficient hardware (like Athlon 200GEs) for homelabs instead of the latest Threadripper CPUs (unless absolutely necessary), a used but dependable car instead of a new one and so on. And, of course, supporting local and small businesses, as well as trying your own hand at some of that stuff - going out to hunt game, drag it back home, skin it and cook it (if nothing else, that really makes you appreciate the meat you're eating), or even just simpler things like growing your own tomatoes and cucumbers (which are absolutely delicious), where possible. If everyone lived at least a bit more like that, we'd have even more breathing room in regards to the environment, in regards to resource usage etc., which feels like a good thing no matter how you look at it. Of course, that's probably also unrealistic as far as expectations go.