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i like it more than 1.5 variant..

since we need about 500 MT to go to mars we have to send it to LEO in small pieces and assemble them it doesn't make that much of a difference if they are 130 MT or 100 MT pieces.. you sent them to LEO, put them together and when ready send orion with crew..

bigest variant (with upper stage) is 100 MT to 60x100 orbit.. that's 200 MT  maximum combined weight.. that's more than 22 + 130 MT maximum for Ares I + V.. and since most of it is propelant, i don't think why it couldn't be done..

no need for 5 segment boster, no need to develop 2 new launch vehicles.. lower cost to run it.. and since this new rocket would be "manrated" with escape tower when it blows up it would still be safer than shuttle.. not prfect, but we are talking about rockets.. soyuz is not perfect, but it hasn't killed anyone in decades..

and later, you could make reusable lander (that would use LOX at least) that would meet in LLO with orion + EDS launched on one 100 MT (or ever 70 MT if that would be feasible.. 22 MT orion + 58 MT EDS?) single rocket.. (Ares V would not be manrated, so you would always have to send crew with different rocket)..

for ISS you would have fuly fueled orion sitting on top of 58 MT cilinder full of stuff, if the rocket blows up and escape tower saves crew then who cares.. if it does not, you dock with orion to cilinder in LEO, fire engines to get to ISS, pick up cilinder with robotic arm (like HTV plans to do), detach orion from cilinder and dock it with ISS.. crew replacement and twice the cargo capacity of the shuttle.. you could even scap shuttle and NASA could still deliver everything it promissed it would..

it would be cheaper and you could develop 5 segment boosters, add one more engine (or 3 more for full ares V), extend fuel tank and get 130 MT to LEO.. less money spent on moon, new rockets, upgrades,... means more money for mars and elsewhere..

what's not to like?

The devil might lay in the details, but there is nothing that could not be solved with simple solutions..

What is so crazy about making cylindrical object spin around it's axis by firing thrusters? bigger only means more propelant, but once it's spinning it will go on spinning forever and you will not need any more propelant.. and since the point of this spinning will to make 1G the stress on rafinery is the same as you would have on earth.. because, that's the point of the spin...

yes, it would be very dificult to dock with a spinning station, but there are two points where you can atach spinning and non-spinning parts.. by.. hmm.. how do we manage to keep tires on moving cars? I hardly think nobody can develop ball bearings (to use the simplest method known) that will last for loong time.. and if something goes wrong, you can break off connection, fix, and redock..

"size and massis is quite extreme" = "useless material that is left"..

Scrap metals gets picked up with things like  that .. they dangle in air and close to grab things.. there is no need for gravity or outside force to grab pieces lying around..  you would have to target things that are sticking from the "surface" and then use force to close scoop.. if you slip just reopen them, and try again.. there is no need to digg in if material is this loose..

if you grab onto some rock you can use it for leverage for drill.. in that case you either manage to drill into rock (if it is solid and strong enough) or you brake off your anchorage point.. either case you get material you need.. and this would defentitly work in a swimming pool..

there is no need to get anything more than pebbles, if you can get many tons of them.. just repeat untill you have enough of them..

why bother with nuclear with 1000s isp and only H2, if you already have H2 and O2 from water that wil give you 450s ips.. and you have more than enough sunlight to process water into propelant and refuel spaceship..

why do this? because if you don't have to send everything from earth, you can send only what you DO need.. there is no way you can build 10.000 MT spaceship on earth and send it to LEO.. but if you can get unlimited propelant, structural materials and such simple things in space, then you only need to send the complicated things.. so that 10.000 MT spaceship becomes 9.500 MT spaceship made from material from space and propelant to get it somewhere and 500 MT electronics and complicated things sent from earth..

and we will need 10.000 MT spaceships if we wan't to send more than few people to mars..

RLV just lower costs.. it doesn't return any money just because it is RLV.. mining operation enables you to build large things in space that can enable you to extract something (gold?) to be sold on earth.. to pay those RLV..

Moon is obvious.. peaks of ethernal light.. you get constant sun, easy access to water if there is any in cold traps..

Mars will probably be around equator.. near the easy to reach subsurface ice (permafrost) and interesting places to explore..

We must learn how to seperate Oxygen from metal oxides.. we know how to do this on earth.. We must learn how to weld metals together.. we know how to do this on earth.. if zero-g causes you problems, then you just build first smelter that spins enough, so it works.. and once you weld your first wheel together, fill it with air, spin.. from then on it's just like earth.. you don't even need to research anything new.. only use what you use on earth..

NASA plans to spend 2,5 billion dollars each time to send 4 people to moon for 6 months (not even to mars).. build everything each time, and throw it away.. and you think my way of thinking is wrong? 

Yes.. space construction.. but if you are working in 1 G environment, protected by few m of concrete from space, its like working on ship on earth.. and since have all the energy that you need (sun shines 24 hours a day, 365 days a year), you can light up your greenhouse, that will give you food and recycle water..

you know.. like those greenhouses that produce food when there is - 70 degress celsius outside.. on earth south pole.. http://www.antarctichydroponics.com/international.htm

You just need to build 'factory' that can melt iron oxides (mirrors and sun?) insert CO or H to remove Oxygen from it, recycle gass, and form this iron into sheets. Repeat. Weld sheets together and.. you have your 1 G spacestation.. how much would this weigh? 10-100 MT? You send it once.. complicated parts? Rapid manufacturing...

http://en.wikipedia.org/wiki/Rapid_prototyping

Then we will just have to build better engines.. if they are made to last 10 times they can be inproved.. to 20.. to 50.. and more.. and make them easy to repleace/fix.. then send one container full of engine parts to LEO and that should cover it.. you don't dump whole car when it's tires wear out..

Oh, tugs/landers WOULD make many missions.. there is all that O2 or watter to move around and containers to be delivered.. especialy if that costs you nothing extra to launch them.. it's not like they have to be rebuilt every time because they must do 10 km/s to get to LEO and airbrake back in one big fireball..

since we are talking about something like ATV or progess.. ATV costs 70 million euros, progress is even cheaper (30 million $?).. but even it costs 500M each.. NASA is planing on building/designing all those things anyway.. so how is 500M reusable lander different than 500M expendable lander? It's the same thing.. reusable lander only has bigger tanker and more/better engines..

and since you reuse them.. you only build them once.. NASA has 15 billions to spend each year.. thats 15 landers/tugs that will last you looong time (you fix them, remember).. costs fall once you don't have to send all that propelant from earth.. and once everything is built, delivered and works.. then you send ocasional new lander/tug, spare parts and lots of payloads.. 20 MT to LEO costs you 100 million $.. Ares V + Ares I + EDS + lander that does the same job (deliveres 20 MT to moon) costs 2,5 billion.. and nothing even exists..

Russian Parom is supposed to have 15 years on orbit life with servicing.. and if you design engines to be easily fixed in orbit, then you only replace engines.. or even only parts that get worn out..

Most of the fuel will be in LEO station (where you convert water or store O2 and H2) lunar orbit/L2 and on moon .. they will not move, so you can aford to reliquify boiloff + chill everything realy good.. that fuel will get transfered to tugs/landers right before they go.. that means it will be there for few days.. only exception would be tug that slowly aerobrakes back to LEO.. but it can cary water, so you don't have boiloff problem.. or O2, but O2 does not boil off that fast.. plus, if you keep your tanks in shade they will be cold..

But they should be... we build them out of steel.. we build them big.. we build lots of them.. and we build them simple.. we keep them in the water but load them with cranes/boats in harbors (only use drydocks to fix them).. hell, we even make ships that cary cryogenic fuel on warm see with capacities of up to 200,000 m3 (LGC).. and that ship has to survive large waves, corosion and storms.. and they cost in millions not BILLIONS..

if you plan on building moon base, you might just ass well build something that's not complete waste of money.. and when you have base that is CHEAP TO RUN it will not end up like Appolo...

who said anything about ONE mirror.. you put LOTS of simple mirrors on the tops of mountains and point them all to one big black box below.. then just throw dirt in it, and move mirrors a little..

like this, only upside down.. http://en.wikipedia.org/wiki/Solar_thermal_energy..

It's spinning? well.. unless it's tumbling horibly then you land on it's axis (like you would on north/south pole on earth).. if it's tumbling then you can use something that would look like a spider and try to grab it.. if rock is strong enough you would be basicly hanging upside down from it.. and you basicly landed on asteoroid and you can start pickin up/minning.. if that part that you grabed brakes off, well.. congratulation - you just picked up part of asteoroid.. put that part to tug, and repeat.. when tug is full start engines to meet with earth, do lunar flyby and you are in earth orbit..

it doesn't matter how big asteroid is.. it matters how much can you get to earth orbit.. even 10m wide would need a lot of propelant.. but if it's delta-v to earth is small enough to get it.. it will be done.. 1982DB needs just 0.06 km/s..

well.. since you must process asteoroids in HEEO, L5, L1, L2, werever.. you will have lots of fuel.. and since you already have almost all the speed that you need... the easy to reach small asteorids will get picked up/mined first.. but once you have few that have water/H2/O2 in them around orbit, you will have more than enough fuel to go to harder ones..

No, I am saying that I don't care what is the best way.. even I can find some ineficient easy ways to get things done.. what it the optimal way is for someone else to find out (remember those billions that will cost to design things)..

And if you see problems that are fundamentaly showstopers, then point them out..

Lander that is reusable can be built. O2 can be extracted on moon. H2 could be sent from earth (even you think this is good idea). IF there is ice on moon you could export it all the way to LEO. If it's not.. well O2 is 90% by weight, so you need to bring only 10% H2 from earth.. but, as I said.. we should send something to check if there is ice.. and if there is, it would be easy to get it (just heat the soil and you have steam).. there is nothing complicated with mirrors and boxes..

Actually.. 10% of know asteroids need less delta-v than to land on moon.. as for 'random sufrace explosions'.. it's not like you work on atomic bomb.. if you have problems with sun heating surface, then just block the sun with some simple deployable sunshade..

It depens what you are transporting.. if you airbrake 100 MT of water into LEO then you get 100 MT of water.. you burn all needed fuel to bring water from moon to LLO/L2, after that tug aerobrakes slowly to LEO.. if O2.. well.. you would need boiloff condensing.. but most of the figures i have seen point to few percent boiloff a month.. so instead of 100 MT of O2 you get 90 MT after a month or two in LEO.. not realy big deal.. the only unknown is heat shield.. but if you made it big enough and did not went to low it would not heat that much so it would not have to be all that strong/heavy..

This is something small, but you can make it bigger.. or hotter.. or slower.. http://aria.seas.wustl.edu/SSC01/papers/11-8.pdf

good point, but you could go to/from polar orbit and L2 at any time.. and lunar orbit would be good for about 4 months before you crased.. enough to refuel and split before you ended on moon..

Yes you would need liquifying station with tank farms.. but, what is so complicated about them that they would need tens of billions of dollars? They are tanks for O2, H2, H2O, cracking plant (basic electolisis - we do this on earth), liquifying (compress, remove heat, expand - liquid) and cooling.. oh and pumping.. and that's it.. it's not like we don't know how to do this things on earth some 100 years.. but even if it does cost a lot of money to develop this thing.. once you developed them you don't have to develop them again.. just build few of them and you are set..

Aerobrake alows you to return from moon with propelant for FREE (propelant wise).. you pay the price with shield and boiloff condenser.. but if you can return more of it to LEO than you need to get tug back to LLO, than it's worth it..

you split it, because you don't need shield, condenser an solar panels on moon (not to launch with them anyway) and you don't need legs on tug, you get two different ships.. but if you didn't need lot of mass to aerobrake, you could just make one.. in any way they would use same engines, electronics, docking/refueling, navigaton.. so actually they are not all that different and most of the things would have to be developed only once..

Why sort it? And how do you sort ice from dust?

I don't think there are big plates of ice lying around.. not if 99% of other material is dirt..

Why not just heat everything untill ice is converted into steam, capture and cool this steam and you have pure water.. you don't actualy even need to capture it.. steam is gas and will expand in space, but since you have everything sealed it can expand only to second box, where it will liquefy or become ice again.. you need heat (mirors) and cold (well.. your box is in a place that hasnt seen sun for a long time..)..

Let us presume that there is ice in permamently dark valeys on north and south lunar poles. It is mixed with dirt and rocks in low concentrations (let us presume 1% of weight is ice, the rest is dirt), and you must deliver water to base where it is used. How would you do it?

I would build base at the top of the mountains which are permamently lit. You have constant sunlight so you can split water into O2 and H2.. I would have a 20 MT rover/digger/transporter, refuel it on the top of the mountain with O2 and H2, then drive to the valeys below.. the digger would probobly weigh around 20 MT, therfore it could cary a lot of dirt. It would have tanks for O2, H2 and H2O, big shovel and even bigger place to carry dirt (it's moon - things are 1/6 earth weight).. It would combine O2 and H2 to power it (and of course it would store that water for reuse), would be automatic or remotly driven (from earth) and localy fixable..

I guess it could easily pick up 30 MT of dirt and drive 10 km, dump it and return to pick up more dirt in one hour. That would mean, that one truck would move 720 MT of dirt a day, containing 7,2 MT of water in it.. you dump this dirt in big black box and seal it.. next you need to heat all of this dirt to 100+ degress celsius.. you do this by simple mirrors that are located at the top of the mountains. since there is no atmosfere on moon it doesn't matter if they are 10 or more km away.. it might be a little tricky seting them up, but since sun moves realy slowly and predictably all you would need are small motors that would move them.. they could be very light.. big box heats up, water boils away, and condenses in cold tanks conected to this box..

all that you would need then is to fill up digger with water and drive it to top of the mountain..

uh.. lot's of coments..

'star base' like that would need lots of material.. but it would be built the same way cruse ships are.. it would actualy be easier to build such star base than ISS.. you need tehnology to smelter/refine metal into sheets, weld this sheets together, once airtight spin, and you would have no idea that you don't work on earth.. everything would work the same.. where do you get material? the same place you get H2O - moon, asteroids, comets..

yes, it will not be easy.. all-reusable, LEO exporting propelant production infrastructure size would be big.. but that is not really the point i try to make..

the point is, that you need to develop space resources to the point where you don't need all that much stuff from earth.. you can start small, but you should know where are you going.. thinking big forces you to focus more on what can you build and how and less on how light something is.. manufacturing.. refueling.. extraction.. if it is too big to send from earth, what it would take to make it from lunar metals..

you build them sturdy and just fly them untill they can fly no more.. new landers would take care of critical stuff (cargo, humans).. old for noncritical (water, propelant, metals or anything else).. plan it soo, that if they fail, there is no big deal.. main obstacle is of course engines, but i have read somewhere comments about RL-10 from designers, that if you don't stress them too much, they will run forever (not really, but you get the point)..

build them sturdy.. build lots of them.. if one breakes, no big deal.. you would use them to send stuff to TEI and to help transfer propelant/water to make this posible.. you could even use them to return material from the rest of solar system..  once you develop them, only costs are to build them and launch into LEO.. if they are built to last 15 years and you have 10 - 100.. of them in various stages of return to LEO.. who cares about travel times.. use the one that is curently checked, loaded and in LEO..

I am not outraged about costs.. but if we plan to send more than 4 people to moon or mars, you have to look at costs.. in a ways ships and spaceships are the best comparisson..

well.. we all agre that we have to check what is there.. and if it is there, how best to extract it.. if there is no or very little Hydrogen there, there would be no point..

you would need a real base.. probably something that is dug into mountain.. so you have lots of space in caves with air so you can do everything as you would do on earth.. you would have machine shop that could make lots of things localy (with stuff like rapid prototyping machines).. complicated parts would be sent from earth, easy parts would be made localy.. no need to develop everything new since only change would be 1/6 gravity.. you would grow your own food and recycle water/air so suport costs would not kill you, and since you could cheaply send more people that could work there, you could.. and if you need more space, just dig deeper.. if you need more power just build more solar panels/reflectors..

you start small.. 4 crew and landing modules.. LOX extraction from dirt.. then slowly add things.. first you send H2 from earth.. digger, small machine shop.. H2 would be sent untill you get your production started.. first you reuse human lander.. later you reuse (or if first ones were single use - send from earth) cargo modules to transport modules form LLO to surface.. later (when you increase Hydrogen production) you can refuel tugs..

you can build converyer belt.. you can build cable carts.. you can make mirrors so you don't need to bring all that soil to the top, but you can heat it from above (inside a big box, so you can capture steam).. there are many ways that depend on specific location..

Mining near-Earth asteroids is less a fable than teraforming Mars, but people still think how it could be done.. asteroids are there.. how you get stuff from them is a engineering problem.. but things get simpler if you have to deal with very small asteroids.. like.. 10 m across.. or one that is not spinning realy fast.. i don't care how it is done if you can get stuff from that rocks to tugs and deliver tugs to earth orbit..

yes.. you have to find hydrogen and carbon.. and deliver it to LEO.. otherwise all this is unfortunate.. moon is a good start and once you have propelant to spare you can get it from other places (comets?).. it's still workable, because you must send H2 from earth, but you can get O2 from moon.

You would only aerobrake into LEO. To get to Lunar orbit you would use propelant.

i read a report that it is posible to aerobrake from GTO to LEO, so i guess it would be posible..

there is no need for stable lunar orbit.. nothing stays in orbit for long.. tug comes from earth, lander from moon.. later they return back..

most of tug's propelant would be in LEO.. on the way back to LEO you could load tug with water so there is no boiloff no matter how long it takes to get there..

there is not one.. there are two ships.. they are similar, but one has legs (lander), other has big panels to airbrake with (tug)..

ok, I will explain one more time...

- Expendable Rocket caries container to LEO. 20 MT waiting to be delivered.

- 'tug' comes, picks up this container, loaded with 30 MT of propelant (H2 and O2), goes TEI, moon orbit insertion and waits in LLO empty (well.. at least without O2.. it could have extra H2 to transfer to lander) for lander.

- 'lander' loaded with 100 MT of propelant goes into LLO, meets with 'tug' picks up container, transfers 15MT of propelant to tug, then returns to moon with container. (if you don't have enough H2 on moon you transfer 'tugs' extra to 'lander' to be stored on the moon)

- another lander launches with 40 MT of water/O2 and 60 MT of propelant. meets with 'tug', transfers water/O2, returns empty to moon. (you can repeat this couple of times.. depeanding how much capacity 'tug' has - more you load it, more time it will take to aerobrake back to LEO)..

- 'tug' starts engines, starts aerobraking and slowly returns to LEO with load of water/O2 (40 - 120 MT)

- once in LEO 'tug' either transfers propelant to LEO depo or electrolises water into H2 and O2 with solar panels for next trip..

cost of moon propelant to bring 20 MT container to moon: 30 + 100 + 60 = 190 MT. Large? Well.. once you have everything running it is free..

But this will work even if you only have O2.. instead of water you return LOX via airbrake to LEO. So you have LEO depo full of LOX, so you only need to send H2 from earth.. 100 MT of hydrogen will get you 100 MT of cargo delivered to moon..

edit: this is from another thread..

You are right.. reuseable lander doesn't make any sense without lunar material utilisation.. but with it.. it changes everything. But to really make everything reusable you would need two diferent LARGE spaceships:

- Lunar lander. It would be basicly large tanks, rockets, legs and place (at the top) where you could put container. It would be big enough to go to LLO pick up container (25 - 100 MT) and land back at moon base (at north pole). If it did this pickup it would launch without container (so it has enough propelant to return with cargo), otherwise it would launch with a crew module to enable docking and trasfer to tug.

- Tug. This would be similar to lunar lander, but it would have no legs. It would have large and strong solar panels and would be strongly built with good insulation. This large panels would provide enough energy to reliquify any cryogenic boiloff (to keep losses at the minimum) and also provide enough area to aerobrake (slowly over a month or soo)..

Ok, how would this make a difference. Let's say you put 100 MT container to LEO (or 25 or whatever). You come with full tug, pick up this container, do TEI and brake to LLO. There you meet up with lander, move this container to lander. Container would be delivered to lunar surface, Tug would sit empty in LLO. You would remove container from lander, refill with propelant (or just use another one - you have more than one), launch to LLO, transfer propelant to Tug and return to lunar sufrace. The tug would do TEI and go to earth, where it would slowly aerobrake to LEO (or use propelant to tranfer to LEO fast). There it could dock with either space station, refueling station, another tug or with another container to transport somewhere. It would be almost full (because of aerobraking) and it could transfer some of this propelant to another tug/refueling station and with the rest go to moon for more..

So 100 MT that Ares puts into LEO is 100 MT that gets delivered to moon. Better yet, you don't have to send propelant from earth for any deep space mission. You can put empty space ship to LEO, refill with propelant from one tug, use another to give it TEI (the tug itself will aerobrake back to LEO) and off you go to Mars or NEA or anywhere else.. you could even use more than one tug, so you could multistage.. you could even send tugs to NEA, pick up water, metals, anything you need and return to LEO with aerobrake.. once in LEO it could be inspected, fixed, upgraded,..

This NASA program IS repeating Apollo. It will cost 500$ everytime you will need to change crews on moon. How long do you thing this will last.. Apollo went to 17..

It will take more to develop, but once you build and launch few tugs, few landers, few fuel factories (one on moon, one on LEO, one on phobos, few on asteroids, one on...).. then the cost of crew exchange drops to cost of one CEV (that would transfer to human container abord tug), soyuz or kliper.. that's few tens of milions $.. and for the rest.. what you couldn't make in space you would launch on cheapest LEO launcher.. you actualy don't even need 100 MT launcher.. you could send both lander and tug to LEO without propelant on smaller rockets, send fuel from earth in containers until everything is runing smothly.. those containers would be usefull later in a propelant depos..

In the short-term you would only put lander on the moon with containers (fuel factory, solar panels, basics).. and the lunar ice is a MUST.. so you land first at Peak of Eternal Light.. you have constant light and constant shade.. if shade has no water, then you must get hydrogen (and probably carbon) from somewhere else (which would be unfortunate).. but then again, lots of data points to presence of water..

robotic lander would really answer lots of questions..

tanker vehicle is needed anyway.. tanker is EDS with means of transferal of propelant..

you would land lander on moon and you could take time to fix it.. there would be more of them, so if one would be broken others would be used untill it is fixed (or used for spares)..

CEV could dock with tanker/tug.. if anything goes wrong CEV would return crew to earth without problems..

cargo LSAM would take off loaded with propelant from moon and would either pick up more cargo or become tanker for tug.. so it would be reused after propelant production would start.. it could also come handy for "hops" around the moon..

You mean any clear advantage for PMWAC as in: "It is proposed here to solve not only (high thrust/ high Isp / high efficency), but to provide the breakthrough technology required to make fusion propulsion a realizable goal in the next decade." ? 

Forget about scooping gasses.. I WANT PMWAC 

Yes, I know.. but they use Xenon because it's inert and easy to keep for long time. As far as I can tell Hall thrusters can use any gass including O2 (the most reactive).

I have looked up data on Smart-1. It has 2 KW solar pannel, Ion drive which has 70 kg of Xenon and ISP 1640. It will use all of it in 200 days.

So If we would have to use half of gasses for thrusting, and we would have 2 MW solar pannels, then we would get 100 tons of usefull gasses / year. More power = more gasses.

Not if you use solar energy to compensate for drag. Let say we build something that looks like stingray. Flat with solar wings, wide mouth to 'scoop' atmosfere, seperate, eject unneeded parts (N2 probobly) with some kind of thruster (with energy from the sun).