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Thread: Space Project I give my students: Mission to Titan

  1. #1
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    Space Project I give my students: Mission to Titan

    Hi. I am a Science Teacher in BC, Canada. I know I am part of the establishment that spreads bad astronomy so please don't kill me 8-[ .

    In grade 9, we have an astronomy unit, mostly the solar system. At the end of the unit I give a project to the students. I give the the hypothetical scenario of establishing a mining/fuel producing station of Titan, in the orbit of Saturn. I chose Titan because it is interesting but not widely known to the students, and because it has volatiles. My parameters are as follows.

    Round trip time: 20 years. Is this reasonable?
    Cargo: 10 miners and 4000 kg of equipment.
    Engines and fuel: I give some of the features of modern space engines, focusing of reaction and ion engines. I state that 4 engines 20 m x 5 m x 5 m and fuel is 2 spheres 40 m in diameter. These must be shown in your design.
    Crew: Choose a crew, or state why none would be necessary.
    Life Support: Again, students must design it based on current technology.
    Gravity: I make the students figure out how to simulate gravity in a spaceship and look at effect of acceleration.

    Budget. The ship doesn't have to be paid for and is being built in high earth orbit. But food, crew, equipment have to be shipped to the ship at current rates, which I call $40,000 USD / kg. They also have to purchase equipment with this budget. The budget is $2.0 x 10^9 USD.

    Generally, I try to get the students to think about some of the problems and costs associated with manned missions.

    Usually, in result, I get 14 outlines of the starship Enterprise divided into rooms like kitchen, make-up room, etc and crews consisting of popular celebrities. But I get one or two well though out projects with ring shaped ships with sophisticated and well though out life support systems.

    So. Any suggestions? Comments. I am curious for feedback from non-teachers who are interested in astronomy.

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    You do this to 14/15 year olds. Ouch. I know a lot of college students that I TA'd that would have had a fit over this. The one comment i would make without first working this out myself is tha tthe rotating sections on a ship might not work. I seem to remember a thread around here a while ago that explained why but basically it had to do with scale. Some help BABBers

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    Coriolis forces would be intolerable if the rotational radius was too small.

    But that's not the real point here, is it? I doubt most high school frosh know enough physics to do a real job, calculating mass ratios and specific impulse, total available deltavee, transfer orbits and the like. I assume that is not the essential point.

    It sounds like you want your students to begin to think critically, proactively and quantitatively. My son did something similar in 7th grade, packing a covered wagon to follow the Oregon Trail. The idea is similar.

    I also assume that you give more data and detail than the bare outline here, and answer reasonable additional questions. I'd be happy to look at it if you want to PM it to me.

    Overall, this sounds like a good idea. I may just ask my son to try it and see what comes out. (he's just started 9th grade).

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    Quote Originally Posted by iamcanjim
    Usually, in result, I get 14 outlines of the starship Enterprise divided into rooms like kitchen, make-up room, etc and crews consisting of popular celebrities.
    Still, that's more thought than Berman and Braga seem to put into an episode.

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    Depending upon how you want to do it, your round trip time of 20 years is absurdly high. An Orion-type spaceship that had 1 G of thrust could probably make the roundtrip (not counting loading and unloading times) in two months.

    With a space elevator on Titan and Earth, getting the stuff from planet to space and back again would be relatively easy.

    Using a set up like that, my WAG, is that it could be done for less than $100 billion USD.

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    Re: Space Project I give my students: Mission to Titan

    Quote Originally Posted by iamcanjim
    Hi. I am a Science Teacher in BC, Canada. I know I am part of the establishment that spreads bad astronomy so please don't kill me 8-[ .

    In grade 9, we have an astronomy unit, mostly the solar system. At the end of the unit I give a project to the students. I give the the hypothetical scenario of establishing a mining/fuel producing station of Titan, in the orbit of Saturn. I chose Titan because it is interesting but not widely known to the students, and because it has volatiles. My parameters are as follows.

    Round trip time: 20 years. Is this reasonable?
    There are a couple ways to work this out. I wrote a Hohmann ellipse routine a whlie back--one way transit time to Saturn is a bit more than 6 years. You could derive this from one of Kepler's laws if you like (square of the period is proportional to the cube of the radius, the radius would be the average of the radius of the Earth's orbit (1 au) and Saturn's orbit (9.6 au). Remember that you only need to go half-way around.

    Anyway, 6 years there, 6 years back. Stay n years.
    Cargo: 10 miners and 4000 kg of equipment.
    Engines and fuel: I give some of the features of modern space engines, focusing of reaction and ion engines. I state that 4 engines 20 m x 5 m x 5 m and fuel is 2 spheres 40 m in diameter. These must be shown in your design.
    Delta V (again from the hohmann program. Old (~1975) CRCs used to have this data, but they stopped carrying it) for the Earth/Saturn injection is 10.3 km/sec to Earth/Saturn transfer ellipse, 5.5 km/sec from Earth/Saturn transfer. That doesn't count planetary escape velocities (11.19 km/sec from LEO, 7.885 km/sec from Saturn at Titan, 2.65 km/sec from Titan). Orbital velocity around Titan is on the order of 1.9 km/sec.

    You need to figure your mission profile--it's cheapest if you can aerobrake into TItan. Assuming that you can, you need on the order of 7.3 km/sec to get you into your transition orbit (this seems too low--maybe someone could check my math. You can't just add delta V's). For the trip home, you'd need on the order of 9.6 km/sec to blast from Low Titan Orbit to the Saturn/Earth transit orbit.

    Oddly enough, this is feasible with chemical propellants, particularly since you're planning on doing some mining on Titan anyway. The main problem will be building the tanks for the return voyage.

    The trip out could be done with a mass ratio of about 5--this could be done with a single-stage craft. The trip back would probably need two stages.

    So. Your initial craft consists of (1) main engines, (2) fuel tanks, (3) mining/ground equipment, (4) habitation module, (5) aerobrake shell.

    I was thinking originally that you would leave something in orbit around Titan, but it might prove cheaper to just launch from the ground. This increases the cost of that stage slightly--up to about 10 km/sec You'll need to add some fudge for gravity losses, so this might be close to 11 or 12 km/sec.

    So your mission looks like (1) assemble in LEO, (2) blast from LEO into transfer orbit (6 years), (3) aerobrake into Titan landing, (4) mine, assemble stages for Titan ascent, (5) direct ascent from Titan to earth transfer (6 years), (6) aerocapture into LEO or earth descent. Obviously you'd leave the mining equipment behind, but you'd need to budget for your return cargo.

    Mining equipment and a ground habitat could be landed in a previous mission--this could change the configuration drastically.

    The ascent from Titan is going to require staging--you'll need to include the engines and complicated machinery for that in your ground package.

    I'd guess a few hundred tons for the habitat module and maybe twice that for the mining equipment. Of course, this depends on what you have to mine. Anyway, on the order of 1000 tons. Pentuple that for fuel for the way up.
    Crew: Choose a crew, or state why none would be necessary.
    Life Support: Again, students must design it based on current technology.
    Sorry, can't be done. Current technology can't do closed life support for a dozen people for 20 years. You'll have to allow for reasonable advances in life support.
    Gravity: I make the students figure out how to simulate gravity in a spaceship and look at effect of acceleration.
    You could pretend as if 20 years at Titan-level gravity isn't going to produce long term disabilities (or else that the crew will be amply repaid for their sacrifice). See if any of them pick up on the changes that will cause to your rotating structure.

    Budget. The ship doesn't have to be paid for and is being built in high earth orbit. But food, crew, equipment have to be shipped to the ship at current rates, which I call $40,000 USD / kg. They also have to purchase equipment with this budget. The budget is $2.0 x 10^9 USD.
    Your cost to orbit is perhaps an order of magnitude too high. You're going to have to have some super-heavy launchers for this; if the BIg Dumb Booster camp has anything going for it, this might drop the price/pound to the $1000 range.

    Note that the price of your mining equipment is still irrelevant--your cost is still dominated by the price to orbit (10,000 tons or thereabouts at $1000/pound is $20 billion).
    Generally, I try to get the students to think about some of the problems and costs associated with manned missions.

    Usually, in result, I get 14 outlines of the starship Enterprise divided into rooms like kitchen, make-up room, etc and crews consisting of popular celebrities. But I get one or two well though out projects with ring shaped ships with sophisticated and well though out life support systems.

    So. Any suggestions? Comments. I am curious for feedback from non-teachers who are interested in astronomy.

  7. #7
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    I wish I could do this in my science class. We have done no experiments or any thing aside from force and matter. I should show this to my teachers (Except Mrs. Kelly AHHH!!!)

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    I doubt most high school frosh know enough physics to do a real job, calculating mass ratios and specific impulse, total available deltavee, transfer orbits and the like.
    Most, not all.

    But I get one or two well though out projects with ring shaped ships with sophisticated and well though out life support systems.
    If you want to use artificial gravity, there are two feasible methods. The first one is to have a wheel rotating about a center truss; you'd have to have another counterrotating one as well. I would use the center structure for systems and propellant; a nuclear reactor would fit in nicely there. You could also design a mission architecture with two or more spacecraft parts rotating about a central point on a long tether, as in the Mars Direct plan, but for a long missoin the counterrortating wheels are more feasible . For a mission of this length, artifical gravity must be used.

    Alternatively, you could have a 1g acceleration spacecraft, but with foreseeable technology that would not be achievable.

    Round trip time: 20 years. Is this reasonable?
    The best engine to use here is probably a NEP (Nuclear Electric Propulsion; a nuclear reactor ionizes a heavy gas, usually xenon, which is then expelled to provide thrust.) If you used a NEP, the round-trip time would probably be on the order of about ten years, which gives you 10 years to build a base there.

    Cargo: 10 miners and 4000 kg of equipment.
    I don't think that 4 tonnes of equipment would be nearly enough; to establish such a base would probably require at least 20.


    I call $40,000 USD / kg
    I agree with daver; this is about an oder of magnitude too high. If you're launching it with foreseeable SSTOs it's probably going to be about $1,000 kg. $100/kg is possible with scramjets and other advanced forms of propulsion.

    The budget is $2.0 x 10^9 USD.
    $2 billion isn't going to get you a thing. Galileo and Cassini cost more than that. For a project of this magnitude, I would budget from $100 billion to $200 billion. $2 billion is just far too low to get anything; your launch costs alone are going to run at least $20 billion, as daver said, if not much more.

    With a space elevator on Titan and Earth, getting the stuff from planet to space and back again would be relatively easy.
    Space elevators are not feasible to build on Earth with any known materials. On Titan you could do it but for these purposes I don't think it would be possible or economical.

    Sorry, can't be done. Current technology can't do closed life support for a dozen people for 20 years. You'll have to allow for reasonable advances in life support.
    I have a teacher who recently made us design a colony in Earth orbit that was closed and could support 24 people for 75 years. I almost started laughing. The designs were ridiculous, too; we had people come up with the brilliant ideas of having water flow downhill, running the entire thing on one solar panel (and having the solar panels provide heat), and they all of course had guns and lasers. One of them required perpetual motion to work (I believe it involved having water turn a turbine, which created electricity, which pumped the water back to the turbine); they all lacked artifical gravity or scientific equipment, and they also lacked attitude control systems.

    Another problem is the sheer mass of this vehicle. Any craft designed to fulfill theese requirements would weigh in excess of 1,000 tonnes and would require at least 10-15 Saturn V class boosters to be used, probably far more. Unfortuantely, for a vehicle of this size, aerobraking is not really possible to do in a safe manner (also, assembling an aerobrake in orbit could prove to be impossible). But the NEP should provide plenty of power.




    Usually, in result, I get 14 outlines of the starship Enterprise divided into rooms like kitchen, make-up room, etc and crews consisting of popular celebrities. But I get one or two well though out projects with ring shaped ships with sophisticated and well though out life support systems.
    Everybody designs the Enterprise. Any realistic design to satisfy these requirements will need to run on an NTR or NEP engine. I predict that no one will make use of reactors. What annoys me with any space project designed by students is that they are always powered by the magical solar panels. Solar panels are not that efficient. They don't provide much heat or energy; even a probe to Mercury could get significantly more energy from a reactor than from solar panels.

    There are two ways you could fuel on Titan. You could either make it from the hydrogen there (you'd have to bring your own oxygen, or I think that you could use an NTR there as well.

    Let us know how things go. I'm sure we could debunk some of teh proposals for you. :wink:

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    Uh, BigJim, did you read my link? Nanotubes are the preferred material for building space elevators and Motorola's just found a way to make them cheaply.

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    Actually, I seriously just fudged the timeframe, using the proposed mission to Mars, scaling up to the distance to Saturn. Didn't bother with long term acceleration etc. I know, bad astronomy, but ..... ops: .

    Keep in mind, I give the students the ship for free, to their design, built in orbit. The 2 billion budget is just for fitting out. Fuel, engines and ship structure are free. I do this because I really can't expect grade 9 students to calculate the mass of complex shapes of alloy, much less manufacturing costs. So, the ship, engines and fuel are the greatest cost, but I don't make the students calculate it. Same for mining equipment or miners. The students merely have to design the ship and then budget for fitting out (life support systems, entertainment, mission equipment, crew, etc). So, if they intend to use hydroponics I make them calculate the cost of water and equipment needed for population levels. Again fuel use, engine power and orbital mechanics are beyond them (and me, for that matter) but they clearly understand life support, entertainment and equipment needed for the mission. Each year the students discover that the cost of the items themselves is dwarfed by the cost of orbital lift.

    As for the mission, I actually did calculate mass of equipment. For the project, I give them a backstory about a colony where the existing miners died, so this is a resupply, not original setup. Based on an existing colony that has been damaged, 4 tons of resupplies makes sense?

    I also ask them to keep in mind that the equipment/miners need to be landed somehow, and leave the methods (landing vehicles, multi stage takeoff vehicle, etc) up to the individual students. I tend to get a lot of creativity in that, but no space elevators yet (will have to see this year).

    I did make an error on cost of orbital lift from earth, but keep in mind, I have the ship being assembled in high earth orbit to keep propulsion req's under control. And I fudged into that the cost of developing bulk launch infrastructure. Currently we have the ability but cheap methods are still really only in prototype form. Keep in mind, the 40 K figure is based not on individual launch but complete infrastructure.

    I also considered the materials recycling is not available using current tech but my current tech req. is to prevent the students from using far out Star Trek style techs and justifying by saying "well it could be developed." I actually let the students use non-current techs if they demonstrate (using refs. of course) that it is on the horizon. So, nutrient recycling yes, intelligent robots, no.

    Actually, many plans have no recycling built in because students realize the weight of food, water and oxygen is not that great in comparison to the mass of the entire ship anyway.

    The neatest project was a student who used Quake to make a 3d map of the ship that you could fly around in.

    Edited for stupid spelling mistakes (when I became a teacher, wasn't I automaticaly supposed to become an amazing speller. Miner = person who removes resources from ground, minor = person under 18 :x )

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    I notice no-one has mentioned Stephen Baxter's book Titan;
    although I am sure many people have read it.
    it is a fascinating study of the problems of a Titan mission using current technology.
    Of course the mission only manages to get there, and there is no way of getting them back;
    but every piece of equpiment used has already been designed or is pretty much solid technology.
    They use Big damn boosters to get stuff into orbit, mostly Saturn V's;
    They land on Titan using a shuttle and Apollo space capsules, use a steam boiler/digester to recycle water and waste, and have a centrifuge to counteract the microgravity.

    Despite this they all die horribly one way or another.
    Great book, and points to the extreme difficulty of real space exploration.

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    Welcome to the Board iamcanjim!

    (Emphasis mine)
    Quote Originally Posted by iamcanjim
    I actually let the students use non-current techs if they demonstrate (using refs. of course) that it is on the horizon.
    Bless you! Referencing seems to be such a rare thing these days I'm always grateful when someone teaches it to students.

    (That's all I wanted to say, you can all go back to Titan now . . . )

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    Re: Space Project I give my students: Mission to Titan

    Quote Originally Posted by iamcanjim
    Hi. I am a Science Teacher in BC, Canada. I know I am part of the establishment that spreads bad astronomy so please don't kill me 8-[ .
    Welcome! You're not part of the establishment that spreads BA. You're part of the establishment that spreads astronomy. Just make it good astronomy and we'll love you :-).

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    Never read that book or even heard of it. Odd, because I am a big SF fan. I chose Titan for the project because
    a. It has volatiles but is not a gas giant
    b. It is suitably distant
    c. It has an atmosphere
    d. Less known than the moons of Jupiter, inspiring more research.

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    Quote Originally Posted by iamcanjim
    Actually, I seriously just fudged the timeframe, using the proposed mission to Mars, scaling up to the distance to Saturn. Didn't bother with long term acceleration etc. I know, bad astronomy, but ..... ops: .

    Keep in mind, I give the students the ship for free, to their design, built in orbit. The 2 billion budget is just for fitting out. Fuel, engines and ship structure are free.
    I don't know if you're familiar with the cycler concept Buzz Aldrin proposed--it's basically a hotel that shuttles back and forth between Earth and Mars. It handles the long-term life support.

    Anyway, a fleet of these could logically be set up between Earth and Saturn (each cycler would have a 12 year orbit, in which case a given cycler would encounter Saturn only every 60 years; if you had six of them you could space them so a cycler would come around every ten years or so). Your launch from earth would carry fuel, food, and equipment, but you wouldn't have to worry about life support.

    Oh--i messed up on my delta V calculation from Titan--i'd forgotten to include the velocity from Titan's orbit around Saturn. This makes a huge difference--the delta V from Titan surface to Earth transfer ends up a bit more than 5 km/sec, which is well within the range of an SSTO. Timing is critical, particularly if you are rendezvousing with a cycler.

    Anyway, if you can use the cycler, your mission gets a lot more doable. In earth orbit, you assemble your Titan SSTO lander (actually, you probably have a fleet--three or four, just in case one breaks). These carry your crew, your four tons of Titan supplies, and enough luxury food for your twenty year mission. Launch to rendezvous with the cycler. Spend six years on the cycler, kick off to rendezvous with Titan. Land on Titan, repair things, refine fuel for your SSTOs, wait for the next cycler to come around, blast off for the cycler, and spend six years waiting for it to get back to earth. Kick off the cycler, aerobrake into Earth landing.

    There's a bit of a problem in deciding what's in the McGuffin mine on Titan that's so valuable. Maybe an anti-aging drug.
    As for the mission, I actually did calculate mass of equipment because for the project. I give them a backstory about a colony where the existing miners died, so this is a resupply, not original setup. Based on an existing colony that has been damaged, 4 tons of resupplies makes sense?
    Sure. It depends on what broke, of course. And if you're feeling squeamish, you don't even have to kill off the miners. Maybe a critical piece of equipment broke, but their life support is still functional. They could have caught the next shuttle home.
    I also considered the materials recycling is not available using current tech but my current tech req. is to prevent the students from using far out Star Trek style techs and justifying by saying "well it could be developed." I actually let the students use non-current techs if they demonstrate (using refs. of course) that it is on the horizon. So, nutrient recycling yes, intelligent robots, no.
    What? No Huey, Dewey, or Louie? You could have called the cycler "The Valley Forge".

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    Quote Originally Posted by daver
    There's a bit of a problem in deciding what's in the McGuffin mine on Titan that's so valuable.
    That's easy. Titan has a methane atmosphere and is thought to have hydrocarbon "oceans." In other words, there's an atmosphere's worth of natural gas, and the "oceans" could, quite possibly, be oil. I can think of a couple of reasons why that might be valuable....

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    Quote Originally Posted by Tuckerfan
    Quote Originally Posted by daver
    There's a bit of a problem in deciding what's in the McGuffin mine on Titan that's so valuable.
    That's easy. Titan has a methane atmosphere and is thought to have hydrocarbon "oceans." In other words, there's an atmosphere's worth of natural gas, and the "oceans" could, quite possibly, be oil. I can think of a couple of reasons why that might be valuable....
    Just how much a gallon are you willing to pay?

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    Quote Originally Posted by daver
    Quote Originally Posted by Tuckerfan
    Quote Originally Posted by daver
    There's a bit of a problem in deciding what's in the McGuffin mine on Titan that's so valuable.
    That's easy. Titan has a methane atmosphere and is thought to have hydrocarbon "oceans." In other words, there's an atmosphere's worth of natural gas, and the "oceans" could, quite possibly, be oil. I can think of a couple of reasons why that might be valuable....
    Just how much a gallon are you willing to pay?
    Look at it like this:
    1.) Estimated costs for a space elevator are $6 billion
    2.) When completed, it'll be able to send payloads into space for $100 a pound, which beats the current costs of $10,000 a pound, by a considerable amount. If you charge $5,000, it's still cheaper than a rocket launch (and vastly more profitable for the elevator owner).
    3.) The nanotube cable conducts electricity, solar panels mounted at the top of the elevator can not only provide power for the elevator, but can send it down the cable, where it can be fed into the local power grid, thus sold for a profit (or at least pay the operating expenses of the elevator).
    4.) The most recent US invasion of Iraq will probably come in around $100 billion or more. (No idea of what the war cost, but the current tab for occupying Iraq is $1 billion a week. Which means we could have paid for one elevator by now.)
    5.) Once the elevator is done launching the Orion-style ships to bring the goodies back from Titan, but before they return, it can be used to put payloads in orbit (not to mention it's still sending electricity Earthward), so this is underwriting the whole cost of the operation before one drop of Titan's methane and (possibly) oil reaches the Earth.
    6.) If this operation is done by US corporations, then the money stays here and doesn't go overseas.
    7.) No worries about screwing up the environment if your tanker springs a leak on the way to Earth.

    In the long run, for those reasons, and ones best not discussed here, it would come out cheaper to suck it from Titan than to keep pumping it from the Earth.

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    Quote Originally Posted by Tuckerfan
    Quote Originally Posted by daver
    Quote Originally Posted by Tuckerfan
    Quote Originally Posted by daver
    There's a bit of a problem in deciding what's in the McGuffin mine on Titan that's so valuable.
    That's easy. Titan has a methane atmosphere and is thought to have hydrocarbon "oceans." In other words, there's an atmosphere's worth of natural gas, and the "oceans" could, quite possibly, be oil. I can think of a couple of reasons why that might be valuable....
    Just how much a gallon are you willing to pay?
    Look at it like this:
    1.) Estimated costs for a space elevator are $6 billion
    2.) When completed, it'll be able to send payloads into space for $100 a pound, which beats the current costs of $10,000 a pound, by a considerable amount. If you charge $5,000, it's still cheaper than a rocket launch (and vastly more profitable for the elevator owner).
    3.) The nanotube cable conducts electricity, solar panels mounted at the top of the elevator can not only provide power for the elevator, but can send it down the cable, where it can be fed into the local power grid, thus sold for a profit (or at least pay the operating expenses of the elevator).
    4.) The most recent US invasion of Iraq will probably come in around $100 billion or more. (No idea of what the war cost, but the current tab for occupying Iraq is $1 billion a week. Which means we could have paid for one elevator by now.)
    5.) Once the elevator is done launching the Orion-style ships to bring the goodies back from Titan, but before they return, it can be used to put payloads in orbit (not to mention it's still sending electricity Earthward), so this is underwriting the whole cost of the operation before one drop of Titan's methane and (possibly) oil reaches the Earth.
    6.) If this operation is done by US corporations, then the money stays here and doesn't go overseas.
    7.) No worries about screwing up the environment if your tanker springs a leak on the way to Earth.

    In the long run, for those reasons, and ones best not discussed here, it would come out cheaper to suck it from Titan than to keep pumping it from the Earth.
    Remember, there is a large gap between 'Carbon nanotubes appear to be a material we could make a space elevator out of' and 'Let me run down to Motorola and buy a 24k mile spool of carbon nanotube cable'.

    Kizarvexis

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    Quote Originally Posted by Kizarvexis

    Remember, there is a large gap between 'Carbon nanotubes appear to be a material we could make a space elevator out of' and 'Let me run down to Motorola and buy a 24k mile spool of carbon nanotube cable'.

    Kizarvexis
    True, but there was also a large gap between Rice University and landing a man on the Moon before the decade was out, but we managed to close it.

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    Quote Originally Posted by Tuckerfan
    Quote Originally Posted by Kizarvexis

    Remember, there is a large gap between 'Carbon nanotubes appear to be a material we could make a space elevator out of' and 'Let me run down to Motorola and buy a 24k mile spool of carbon nanotube cable'.

    Kizarvexis
    True, but there was also a large gap between Rice University and landing a man on the Moon before the decade was out, but we managed to close it.
    I'm not saying that someday we might have a space elevator, just don't hold your breath waiting for one. It could be as long as the next century or more. Remember, we are only 20 years away from practical fusion power.

    Of course, someone might make a big leap and we could start one in the next decade, who knows. But my bet is on longer rather than shorter.

    Kizarvexis

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    Quote Originally Posted by Kizarvexis
    Quote Originally Posted by Tuckerfan
    Quote Originally Posted by Kizarvexis

    Remember, there is a large gap between 'Carbon nanotubes appear to be a material we could make a space elevator out of' and 'Let me run down to Motorola and buy a 24k mile spool of carbon nanotube cable'.

    Kizarvexis
    True, but there was also a large gap between Rice University and landing a man on the Moon before the decade was out, but we managed to close it.
    I'm not saying that someday we might have a space elevator, just don't hold your breath waiting for one. It could be as long as the next century or more. Remember, we are only 20 years away from practical fusion power.

    Of course, someone might make a big leap and we could start one in the next decade, who knows. But my bet is on longer rather than shorter.

    Kizarvexis
    Well, I can't find a listing of the folks who're shelling out money for a space elevator, but I've seen one, and considering the big names they've got on it, I'm betting the odds are better than the ones you've posted. (Of course, I wouldn't be surprised if you turned out to be correct.)

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    I'm not in a hurry; the space elevator can wait until we have better technology.

    Titan is a good source of volatiles which are needed on Mars, Venus and Mercury; eventually there will be chains of cyclers moving water, carbon and nitrogen round the solar system in exchange for high tech machinery (and perhaps antimatter manufactured near the Sun)...
    but this could be 900 years from now or more from now...

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    2,138

    Re: Space Project I give my students: Mission to Titan

    Quote Originally Posted by iamcanjim
    Hi. I am a Science Teacher in BC, Canada... I (gave my students)... the hypothetical scenario of establishing a mining/fuel producing station of Titan, in the orbit of Saturn. I chose Titan because it is interesting but not widely known to the students, and because it has volatiles...
    This sounds like an imaginative project for students on many levels. I hope you'll post some of their ideas here later. :wink:

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