Cancer Posted January 19, 2012 Report Share Posted January 19, 2012 Re: More space news! Hubble was intended to be human serviceable in orbit, but in no way was it constructed in orbit. And notably, no subsequent space observatory has even human serviceability built into it. Ideally, HST was intended to have swappable modules that could installed while in orbit, but nothing, absolutely nothing, is actually built up there beyond bolting together ISS modules which are fabricated in toto on Earth. And that's what needs to change, IMO. HST is in a low enough orbit that it needed "boosts" every half-dozen years to keep it from coming down. The last such boost has happened. The other three things you mention ... ISS, Mir, Skylab ... explicitly were/are human habitation facilities in space. Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted January 19, 2012 Report Share Posted January 19, 2012 Re: More space news! My point was that even when something is designed to be serviceable/repairable/(buildable?) in space/orbit, it is by no means easy, even for a highly trained astronaut on-site. Trying it through a telepresence robot might not affect the difficulty, but I can't see it making any building/servicing/repairing task *easier*. Thus I think the inherent difficulty due to the environement is going to require at least a minimal human presence to ensure the highest degree of quality/safety as they will be the QA/troublshooters. Admittedly, this is all IMO and YMMV. Quote Link to comment Share on other sites More sharing options...
tkdguy Posted January 19, 2012 Author Report Share Posted January 19, 2012 Re: More space news! Martian Rocks Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted January 19, 2012 Report Share Posted January 19, 2012 Re: More space news! First photo of liquid water on Mars! [ATTACH=CONFIG]41366[/ATTACH] Quote Link to comment Share on other sites More sharing options...
Old Man Posted January 19, 2012 Report Share Posted January 19, 2012 Re: More space news! I would think that would have been a given -- otherwise' date=' that would make it look like I was saying we should ship the parts from Earth Surface, to Moon Surface, then *back* to Moon Orbit. [/quote'] Right, but it seems to me that the industrial base on Earth is more advanced than the one on the moon currently. Fabricating parts and even processing ore in hard vacuum ups the difficulty level some. (Bolded for emphasis) Based upon what I have seen with the Hubble, ISS, Mir, and Skylab, IMO it would be pretty much a requirement to have at least a couple humans on location, with the rest of the "workforce" being automation/telepresence. Thus, some minimal habitation requirement. Not necessarily occupied full-time, just while there is a construction project going. This more or less matches up with what I was thinking. Quote Link to comment Share on other sites More sharing options...
McCoy Posted January 19, 2012 Report Share Posted January 19, 2012 Re: More space news! (Bolded for emphasis) Based upon what I have seen with the Hubble' date=' ISS, Mir, and Skylab, IMO it would be pretty much a requirement to have at least a couple humans on location, with the rest of the "workforce" being automation/telepresence. Thus, some minimal habitation requirement. Not necessarily occupied full-time, just while there is a construction project going.[/quote'] Thing about telepresence is the speed-of-light pause. We see that in the Mars Rovers where the operator tells it to move an inch than checks back in 40 minutes to see if it did it right. So even with telepresence, until we have full AI robot assembly the "shirtsleeve" environment needs to be as close as practical to the job site. That's kind of what I imagine exploration of Mars will be like, humans directing mobile probes from an underground habitat and going out on the surface only when necessary. Right' date=' but it seems to me that the industrial base on Earth is more advanced than the one on the moon currently. Fabricating parts and even processing ore in hard vacuum ups the difficulty level some.[/quote'] Really? I haven't looked into it, but I assumed ore processing would be easier without all that highly reactive oxygen around. Different from what we are use to no doubt, but more difficult? Quote Link to comment Share on other sites More sharing options...
Old Man Posted January 19, 2012 Report Share Posted January 19, 2012 Re: More space news! Really? I haven't looked into it, but I assumed ore processing would be easier without all that highly reactive oxygen around. Different from what we are use to no doubt, but more difficult? More difficult because it's different. There's no highly reactive oxygen, but then you can't just ship over slightly modified versions of the fossil fuel-driven equipment we use here, either. You would have to invent a low-g, hard vacuum, remotely operated ore processing and machining operation from scratch. Over the long term it'd still be the way to go, but it will take a while before it'd be cheaper than just launching from Earth where all the manufacturing is, despite the higher g. Quote Link to comment Share on other sites More sharing options...
Cancer Posted January 19, 2012 Report Share Posted January 19, 2012 Re: More space news! ... except that everything you send up has to pass through the keyhole that is the maximum booster payload. And I think that's a crucial limitation. Quote Link to comment Share on other sites More sharing options...
megaplayboy Posted January 19, 2012 Report Share Posted January 19, 2012 Re: More space news! In early 21st century propulsion tech terms, what's the practical upper size limit for Super-Heavy Lift Launch Vehicles nowadays? Could you build one that could put 100-200 tons into LEO? Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted January 20, 2012 Report Share Posted January 20, 2012 Re: More space news! ... except that everything you send up has to pass through the keyhole that is the maximum booster payload. And I think that's a crucial limitation. So, to get around this, after developing the "low-g, hard vacuum, remotely operated ore processing and machining operation" that "has to pass though the keyhole that is the maximum booster payload", and getting it operational on the Moon -- you use it to build *bigger* versions on the Moon. The one(s) sent up only have to get the ball rolling. MOOII taught me the value of using industry to build bigger industry capacity. Quote Link to comment Share on other sites More sharing options...
Zeropoint Posted January 20, 2012 Report Share Posted January 20, 2012 Re: More space news! That's the problem; none of our politicians are looking at this from the 4X perspective. Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted January 20, 2012 Report Share Posted January 20, 2012 Re: More space news! That's the problem; none of our politicians are looking at this from the 4X perspective. We need more Strategy/Simulation gamers in government. Quote Link to comment Share on other sites More sharing options...
McCoy Posted January 20, 2012 Report Share Posted January 20, 2012 Re: More space news! We need more Strategy/Simulation gamers in government. There are plenty, but they are mostly in the DOD. Myself, I'm more than willing to allow the military to foot the bill for developing the infrastructure, but some people seem to want no space program if the alternative is one with the military involved. Quote Link to comment Share on other sites More sharing options...
megaplayboy Posted January 20, 2012 Report Share Posted January 20, 2012 Re: More space news! Well, I think people have come to terms with the military killing people on land and sea and in the air, but would rather not extend that to outer space. Or from outer space, for that matter. I still think there's a pretty major bottleneck over the next couple hundred years--let's say, for the sake of argument, over the next 100 years we can develop to the point that we can launch 2 super-heavy launch vehicles from Earth every single week, and loft, say, 1000 tons into low-earth orbit, and/or send 200 tons directly to the Moon. Then let's assume, rather optimistically, that between a Moon facility and stable bases located in the Asteroid belt, that we could put another 10,000 tons per week into space from there, beginning one century from now. Well, wow, that's half a million tons a year, sounds awesome, right? Well, now think about the logistical requirements--fuel, habitation, life support, food, experts, etc.--required for truly deep system exploration(let alone extra-solar colonization of a nearby star system), travelling at a speed between .001 c and .01 c. It'd take decades to get to the Oort cloud, and decades more to build a stable, self-sustaining habitat there, for research, refueling and some manufacturing/assembly. Eventually, let's say we get to the point where we've assembled our first multi-million ton colony ship(following the dispatch of many unmanned probes), and we've developed our propulsion tech to the point that we can propel it at 0.1 c to a near star with a "Goldilocks" planet, let's say we get lucky and it's within 20 light years. That's a 200 year trip, with a multi-million ton vessel. Quote Link to comment Share on other sites More sharing options...
Cancer Posted January 20, 2012 Report Share Posted January 20, 2012 Re: More space news! ... and we've developed our propulsion tech to the point that we can propel it at 0.1 c to a near star with a "Goldilocks" planet' date=' let's say we get lucky and it's within 20 light years. That's a 200 year trip, with a multi-million ton vessel.[/quote'] What few statistics are available from the Kepler mission at this point seem to indicate such planets are pretty rare, and with fewer than a hundred F, G, or K stars within 10 parsecs (32.6 l-y), it seems really unlikely there's one in that 20 l-y you mention. Quote Link to comment Share on other sites More sharing options...
megaplayboy Posted January 20, 2012 Report Share Posted January 20, 2012 Re: More space news! What few statistics are available from the Kepler mission at this point seem to indicate such planets are pretty rare' date=' and with fewer than a hundred F, G, or K stars within 10 parsecs (32.6 l-y), it seems really unlikely there's one in that 20 l-y you mention.[/quote'] Well, that would provide a plausible answer to the Fermi Paradox--we haven't made contact with another sapient species because 1) they're too far away, and 2) space colonization is wildly impractical for any species that isn't dramatically more advanced/resourceful than our own. Quote Link to comment Share on other sites More sharing options...
Zeropoint Posted January 21, 2012 Report Share Posted January 21, 2012 Re: More space news! The asteroid belt should be one of our first stops--there are millions of tons of structural and precious metals sitting around out there for the taking. The value of just ONE typical metallic asteroid would pay for the development and production of a mission to get it and then some, although putting all that stuff on the market would probably depress the prices something fierce. Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted January 21, 2012 Report Share Posted January 21, 2012 Re: More space news! Well' date=' that would provide a plausible answer to the Fermi Paradox--we haven't made contact with another sapient species because 1) they're too far away, and 2) space colonization is wildly impractical for any species that isn't dramatically more advanced/resourceful than our own.[/quote'] Or determined... Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted January 21, 2012 Report Share Posted January 21, 2012 Re: More space news! The asteroid belt should be one of our first stops--there are millions of tons of structural and precious metals sitting around out there for the taking. The value of just ONE typical metallic asteroid would pay for the development and production of a mission to get it and then some' date=' although putting all that stuff on the market would probably depress the prices something fierce.[/quote'] I don't think mining the asteroid field will ever be able to pay for itself, not without some new, vastly more powerful, vastly cheaper, propulsion system. At the last DragonCon, I talked to Dr. Phil Plait about the asteroid field, and he said that even if you collected all of it together, it wouldn't even be the size of the Moon. The total mass of the asteroid belt is estimated to be 2.8×1021 to 3.2×1021 kilograms' date=' which is just 4% of the mass of the Moon.[2] The four largest objects, Ceres, 4 Vesta, 2 Pallas, and 10 Hygiea, account for half of the belt's total mass, with almost one-third accounted for by Ceres alone.[3][4] (That's not even as much mass as Pluto by itself has, which is only about 20% the mass of the Moon.) Couple that with the sheer size/volume that that little bit of mass is spread over, and wholesale mining is IMO right out. Targeted mining of a specific body might work, but once it is mined out, I think *that* mission would be over. And unless humanity has spread itself out further than the asteroid field, selling the metals won't be the point of any mining -- using it to manufacture something out there would be the point. Quote Link to comment Share on other sites More sharing options...
McCoy Posted January 21, 2012 Report Share Posted January 21, 2012 Re: More space news! Well' date=' that would provide a plausible answer to the Fermi Paradox--we haven't made contact with another sapient species because 1) they're too far away, and 2) space colonization is wildly impractical for any species that isn't dramatically more advanced/resourceful than our own.[/quote'] Or determined... Or long lived. Or patient. Or better at setting long range goals. Trouble with trying to solve the Fermi paradox is the solution has to apply to every tech savvy species that might ever evolve. Interstellar colonization is either impossible or highly, highly improbable. But if it is highly improbable, that first species that hits the jackpot will be the 800 pound gorilla. For that reason, if no other species has done it, I think we should give it our best try. Quote Link to comment Share on other sites More sharing options...
IndianaJoe3 Posted January 21, 2012 Report Share Posted January 21, 2012 Re: More space news! What few statistics are available from the Kepler mission at this point seem to indicate such planets are pretty rare' date=' and with fewer than a hundred F, G, or K stars within 10 parsecs (32.6 l-y), it seems really unlikely there's one in that 20 l-y you mention.[/quote'] I think you're being somewhat pessimistic (although you may have access to better data than I do). At this point in its mission, the alien equivalent of Kepler wouldn't have confirmed the existence of the Earth. Quote Link to comment Share on other sites More sharing options...
Gnaskar Posted January 23, 2012 Report Share Posted January 23, 2012 Re: More space news! Can we define colonize/colony in this context? Permanent infrastructure with rotating personnel? People intentionally making a one way trip? People going with the intent of having/raising kids there? The ISS model would be a satisfactory start. So permanent or semi-permanent infrastructure with rotating (but constant) crew. A constantly crewed colony does of course open the theoretic possibility of someone choosing not to return. I wonder if it wouldn't be easier to replace step four with a Mars colony. It's much further' date=' but it also seems easier to set up a colony on a body that has some atmosphere as well as greater quantities of water ice. Eventual terraforming of Mars also seems like a feasible, if very long-term, goal--more so than trying to terraform the moon at least.[/quote'] That is my regular opinion, yes, though there are compelling arguments for both sides. The reduction in necessarily supplies for a Moon mission (due to travel time and return options) verses the ISRU (AKA space farming) possible on Mars. Lunar aluminium and solar power verses Martian methane and geothermal power. The lighter Mars suits verses the already tested moon suits. Low lunar gravity verses aerobraking into Mars orbit. The coolness of a colony you can see from Earth verses the coolness of living on Mars. But even if it is assembled in orbit' date=' any parts that are boosted up from Earth still have to pay that energy price to Earth orbit. Would it make more sense to have the spaceyard in Lunar orbit, using parts boosted up against the much weaker lunar gravity?[/quote'] Manufacturing components of the kind required is a very complicated business that requires an integrated industrial complex. The way we do it right now just assumes the availability of air' date=' water, and free life support, too. So parts pretty much have to come from Earth for the foreseeable future, I'd think. Reaction mass is entirely another matter. The crazy part of the big projects has always been the amount of rocket fuel we end up lifting into orbit. Unlike integrated circuits and titanium rods, there's plenty of oxygen and hydrogen up there.[/quote'] For once we agree completely. Besides, the Moon doesn't really have any high concentrations of useful materials. The lack of any volcanic activity means no mineral veins as such, making mining hugely energy demanding. And with no renewable energy sources appart from (imported) solar power, getting a sufficient operations going would be expensive. In early 21st century propulsion tech terms' date=' what's the practical upper size limit for Super-Heavy Lift Launch Vehicles nowadays? Could you build one that could put 100-200 tons into LEO?[/quote'] Within the next five years? The Falcon Heavy with 53 tons. If the Senate Launch System isn't cancelled next time the senate has an election we might have 70 tons available (at roughly ten times the launch cost of the Falcon Heavy). The strongest engine ever built, the Soviet RD-170, produces 15 times the thrust of the Falcon's Merlin (with the same efficiency). A theoretic RD-170 variant of the Falcon Heavy would be in the 600 tons class, and weigh around 16 kilotons on the launch pad. More realistically, the american RS-68 is still in production, and could produce a 200 ton class vessel with the Ares V program (the Ares V was about 15 years from deployment when cancelled). I don't think mining the asteroid field will ever be able to pay for itself' date=' not without some new, vastly more powerful, vastly cheaper, propulsion system. At the last DragonCon, I talked to Dr. Phil Plait about the asteroid field, and he said that even if you collected all of it together, it wouldn't even be the size of the Moon.[/quote'] Irrelevant. The Moon is largely made of useless rock. The asteroids are pretty evenly divided between metal, rock and volatiles. Add the fact that virtually all of these materials are within a kilometer of the surface makes them damn easy to mine (compared to the moon). Quote Link to comment Share on other sites More sharing options...
McCoy Posted January 23, 2012 Report Share Posted January 23, 2012 Re: More space news! Besides' date=' the Moon doesn't really have any high concentrations of useful materials. The lack of any volcanic activity means no mineral veins as such, making mining hugely energy demanding. And with no renewable energy sources appart from (imported) solar power, getting a sufficient operations going would be expensive.[/quote'] And we can state that as a fact from half a dozen sample return missions? "It was raining on Mongo that morning." Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted January 23, 2012 Report Share Posted January 23, 2012 Re: More space news! The asteroids are pretty evenly divided between metal' date=' rock and volatiles. Add the fact that virtually all of these materials are within a kilometer of the surface makes them damn easy to mine (compared to the moon).[/quote'] "within a kilometer of the surface" is easy to say when (afaik) most of them are already that size. The difficulty I was talking about was the huge distance from one "mining site" to the next. Quote Link to comment Share on other sites More sharing options...
Lawnmower Boy Posted January 23, 2012 Report Share Posted January 23, 2012 Re: More space news! And we can state that as a fact from half a dozen sample return missions? "It was raining on Mongo that morning." There's a place for skepticism, and a place for planning. We have a theory, to this point well supported, about what mineral distributions are like on the Moon and in the asteroid belt. Now it's time to plan our future in space. That means working on our best understanding of what's out there, not acting out randomly on the basis that our theories might be wrong. Will they turn out to be wrong? Maybe. Who knows? Boy, will there be egg on our face if that happens! But there'll be a lot more, and justifiably so, if we go ahead and build Moonbase Alpha on the hope that mining the Moon will turn out to be practicable. As for mining the asteroids, remember that it's not distance between individual asteroids that concerns us, any more than mine developers worry about how far apart mining sites are. It's the economics of mining a particular asteroid and moving the output where it's useful. Because of the perceived low cost of extraction and the favourable energetics of getting there and back, the asteroids look like our best target. Will we turn out to be wrong? See above. Quote Link to comment Share on other sites More sharing options...
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