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Going To Mars Via the Moon (mit.edu)

Posted by Soulskill on from the get-your-moon-to-mars dept.

An anonymous reader writes: Getting anywhere in space is a difficult proposition — at least, if you want to get there in a timely manner. Rocket propulsion requires combustion mass. The more mass you take, the more you need. A team at MIT has found that establishing fuel-generating infrastructure on the Moon could reduce launch mass for missions to Mars by up to 68%. "They found the most mass-efficient path involves launching a crew from Earth with just enough fuel to get into orbit around the Earth. A fuel-producing plant on the surface of the moon would then launch tankers of fuel into space, where they would enter gravitational orbit. The tankers would eventually be picked up by the Mars-bound crew (PDF), which would then head to a nearby fueling station to gas up before ultimately heading to Mars." The technology to make this happen is not difficult to build; it just requires a lot of money. Once it's in place, it'll cut down on expensive launch costs. As the commercial space industry gets going and launches happen more often, such an investment starts to make more and more sense.

95 of 151 comments (clear)

  1. There must have been fuel on Moon... by 140Mandak262Jamuna · · Score: 5, Funny

    At some point in the past the Moon must have had lots of fuel. Oil most likely. Look at all the bomb craters on its surface visible even today. If didn't have oil why would have anyone bombed it? QED, the Moon had oil. It still might, but till unless we get the Moonstone XXL pipeline approved, it will remain unexploited.

    --
    sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
    1. Re: There must have been fuel on Moon... by Darinbob · · Score: 4, Interesting

      Of course the rich Republicans drive around in $80,000 luxury pickups to try and show that they're from a working class country background.

    2. Re:There must have been fuel on Moon... by peragrin · · Score: 4, Insightful

      So is Space X. or did you not know that space X primary funding comes from doing launches for NASA?

      NASA's budget is such a mess because NASA was always required to give no bid contracts for the big jobs to certain companies in certain states. That was congress's doing. Give NASA a fixed budget and let them decide where to procure items and the costs of space travel for NASA would have fallen sharply.

      --
      i thought once I was found, but it was only a dream.
    3. Re:There must have been fuel on Moon... by VernonNemitz · · Score: 4, Interesting

      While the lead comment of this particular thread is funny, there actually is fuel on the Moon, in the form of oxygen in rocks, and hydrogen from the Solar Wind. There is also plenty of solar energy available, for cracking oxygen loose from the rocks, and for collecting/concentrating the hydrogen. Let us imagine a Moon-girdling system of solar power collectors and hydrogen collectors, plus power transmission lines so a single large oxygen-extraction plant can operate continuously even when it is night on the Moon.
      NOW imagine we aren't the only species in the Universe that does something like that. If they use Alternating Current in those power-transmission lines, then we could put radio telescopes on the Moon and detect radio waves of the AC-power frequency from distant civilizations. (Can't detect any AC from a home-world that has an ionosphere; can only detect AC from airless worlds.) If they use Superconducted Direct Current, we are out of luck with respect to detecting them. Note AC could be cheaper than SDC, but SDC will be more energy-efficient --yet stellar energy is "free" after the capital cost of infrastructure, so some alien civs might use AC and others might use SDC (and I have no idea which we might use, unless we decided to be paranoid and use SDC to be less detectable).

    4. Re: There must have been fuel on Moon... by The+Grim+Reefer · · Score: 1

      Of course the rich Republicans drive around in $80,000 luxury pickups to try and show that they're from a working class country background.

      They are also for family values and oppose gay marriage. But are the ones caught in extramarital affairs. Both hetero and homosexual.

      Of course Democrats are all for stopping global warming, but fly around on private jets and have five star hotel sized homes. . They are also supposed to be for the poor. Unless they get too close to them on a non-election year.

      I'm so tired of the two party system in the US. Both sides are full of shit. It's to the point that I look at them like they're more of a sports team than having anything to do with governing the country. Nobody even listens to what they say anymore, or seem to remember all of the campaign promises that they completely renege on once in office when they come up for reelection. GO TEAM (BLUE/RED)!!!

      Hell, it's getting hard to even find a decent independent to vote for anymore. Most of them are someone from one of the two parties that the party lost confidence in, in winning a reelection. So they run as an "independent". But vote as if they are in the same party that tried to throw them under the bus.

    5. Re:There must have been fuel on Moon... by DanielRavenNest · · Score: 2

      There's much more fuel that is easier to reach in Near Earth Asteroids. They are easier to reach partly because you can use the Moon itself for a gravity assist maneuver, and partly because you can reach them entirely with electric thrusters, that are 10x as efficient as chemical rockets. And you don't need an 11,000 km power line to operate continuously. You just need an orbit that is not so close to the Moon you spend time in its shadow.

    6. Re:There must have been fuel on Moon... by MobSwatter · · Score: 1, Informative

      Actually the best fuel there is He3, extremely rare on earth but abundant on the moon.

    7. Re:There must have been fuel on Moon... by Required+Snark · · Score: 2
      North Dakota has a NASA program. That was just the state I picked at random because it is not known for any big academic research or high tech centers. I am sure it is true for South Dakota, Montana, or other low population mostly rural states.

      It begs the question: is NASA chartered for space activities or is it a source of pork for every state, no matter how irrelevant? The answer is obvious. NASA has to grease everyone's palm to get any money at all.

      This would not be so evil if they had a decent budget in the first place. It would be reasonable for NASA's charter to include everyone no matter what state they live in. But the reality is that they have become horrifically politicized to the point that it is hurting their space charter.

      So it's even worse then the effective policy that NASA and the USAF have to spend much of their budgets on Boeing, and that SpaceX is always marginalized. The pork and favored status for incumbent vendors is just another example of how NASA is pure pork from the budget perspective. It's amazing that any science happens at all.

      --
      Why is Snark Required?
    8. Re:There must have been fuel on Moon... by Applehu+Akbar · · Score: 1

      NASA is not "subsidizing" Space X by buying stuff from it any more than we are subsidizing Toyota when we buy cars. NASA buys launch services from a competing variety of companies, foreign and domestic.

  2. another idea by Anonymous Coward · · Score: 1

    They could launch fuel into orbit from Earth with existing launch platforms and then have the Mars bound mission collect all the fuel tanks before proceeding on to Mars. The moon base would likely be more efficient, but this still wouldn't require a massive new rocket that could launch all the fuel and the Mars space craft at once.

    1. Re:another idea by Anonymous Coward · · Score: 3, Interesting

      I think the idea is to launch the fuel into orbit FROM the moon.

      1.) Goto Moon
      2.) Mine/Generate fuel
      3.) Launch fuel into orbit - this step is key
      4.) Launch smaller payload from Earth
      5.) Payload meets fuel in orbit around the Moon
      6.) Payload continues to Mars

      If you only have to launch the payload with limited fuel, you don't need to use fuel to get other fuel into orbit. Also, the Moon has a much smaller gravity well and NO air resistance so launching anything into orbit around the moon is much more efficient than launching something into Earth orbit - this step 3 and I think where the 68% savings is supposed to come from. You only need rockets big enough to get a payload off the Earth and fuel into Lunar orbit - there is no need for the one big rocket launching everything at once.

    2. Re:another idea by dpidcoe · · Score: 1

      But how many times do you need to launch fuel from the moon to cover the cost of all the launches of fuel generating equipment required to build the infrastructure to build the fuel processing plant?

    3. Re:another idea by DanielRavenNest · · Score: 4, Interesting

      An asteroid mining tug can bring back about 200 times it's starting mass over a reasonable operating life, making multiple trips. The right kind of asteroid is 20% carbon compounds and water, which can be reformed to hydrocarbons + oxygen, i.e. high thrust rocket fuel. So the fuel return ratio is 40:1. Extracting the carbon compounds and water requires an oven, which is pretty easy to do with sunlight and mirrors. You also need an electrolyzer, to split the water, refrigeration to liquefy the oxygen, and hydro-cracking unit to add the Hydrogen to the carbon compounds (they are typically polycyclic aromatics).

      If you do the processing in high orbit near the Moon, like the L2 point, you can skip the launch step and just dock and tank up.

      Most people also don't know you can "scoop mine" the Earth's upper atmosphere from orbit. Skimming air at 200 km altitude requires adding 7.5 km/s of velocity to bring it to orbit, but electric thrusters have exhaust velocity of ~30-50 km/s. Therefore a fraction of the air you scoop up can make up the drag you create. You need lots of solar arrays to power the thrusters, but they can power bringing multiple times their own mass in air to orbit. The part you keep can be used as additional propellant for other missions, or as air for breathing, or as 8/9ths of the mass of water (you still need to bring the Hydrogen somehow).

    4. Re:another idea by tomhath · · Score: 2

      Please learn something about orbital mechanics. If you have enough fuel to reach the L2 point and "just dock" you have enough fuel to go anywhere in the solar system. It isn't like flying an airplane.

    5. Re:another idea by Talderas · · Score: 1

      If you have enough fuel to reach the L2 point and "just dock" you have enough fuel to go anywhere in the solar system. It isn't like flying an airplane.

      I believe it still requires more fuel to sun fall but that's of questionable value.

      --
      "Lack of speed can be overcome. In the worst case by patience." --Znork
  3. "...it just requires a lot of money." by turkeydance · · Score: 4, Insightful

    the rest is just commentary.

    1. Re:"...it just requires a lot of money." by CrimsonAvenger · · Score: 1

      the rest is just commentary.

      Point is that it doesn't require any new technology to do.

      Note that similar ideas have been being floated for decades. The basic tech required is '80s tech, not 21st century....

      --

      "I do not agree with what you say, but I will defend to the death your right to say it"
    2. Re:"...it just requires a lot of money." by fsagx · · Score: 2

      Forget the money. I want to know more about this gravitational orbit thingy.

    3. Re:"...it just requires a lot of money." by ShanghaiBill · · Score: 2

      Point is that it doesn't require any new technology to do.

      Yes it does. With current tech, it will cost a trillion dollars ... which means it will NOT happen. We need new, much cheaper, technology.

    4. Re:"...it just requires a lot of money." by NicknameUnavailable · · Score: 1

      True, though if for instance The Gates Foundation were to invest in it instead of pissing away money on the third world the amount of usable area available to civilization would multiply for the first time in centuries.

    5. Re:"...it just requires a lot of money." by painandgreed · · Score: 1

      Point is that it doesn't require any new technology to do.

      Depends on what you mean by "new technology". The theory is understood and probably does not require any more theoretical understanding of the problem (although there might be some new theories that might make things easier). It will however require lots of new engineering, development of new equipment, testing, and interactive refinement of said equipment. We are still figuring out how to land where we want to without issue, have never set up industrial equipment on either the moon or an asteroid, have never harvested industrial amounts of material, nor got an entire industrial supply chain working in space (probably by remote control) reliably to actually make use of the end products. None of this has been done yet even as a proof of concept. Just getting a proof of concept example done is going to take a lot of work and many decades.

    6. Re:"...it just requires a lot of money." by RockDoctor · · Score: 1

      the amount of usable area available to civilization would multiply for the first time in centuries.

      how so? Are you talking about the million-year programme of terraforming Mars into a high-maintenance planet which would be filled with humans in less than 100 years.

      Quick reality check - which has more land area : Earth or Mars? Earth, by an area considerably smaller than Antarctica. Which is vastly more hospitable than any area of Mars.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
  4. Re:We have top men investigating this. by fizzer06 · · Score: 1

    Alice Kramden, 1st woman on the moon.

  5. just go somewhere!!! by bkmoore · · Score: 4, Interesting

    I would rather NASA goes somewhere, even the Moon, than plans to go somewhere even better, such as Mars, but never gets off the ground. The Mars discussions are like the Wright Brothers complaining it's not worth building the Wright Flyer until they solve how to cross the Atlantic, because who really wants to fly 259.7 meters on a sandy beach.

    1. Re:just go somewhere!!! by ShanghaiBill · · Score: 3, Informative

      I would rather NASA goes somewhere, even the Moon

      Why? What is the reason to send a can of meat to the moon, for the a thousand times the cost of sending a robot to do the same mission?

    2. Re:just go somewhere!!! by CanadianMacFan · · Score: 4, Insightful

      Well, if you want to send people anywhere else the moon is an excellent place to try things out because if it goes pear shaped you are only a couple of days away from Earth. Once you are confident of the technologies working on the Moon then you can go forward to Mars with more confidence because Mars isn't such an extreme environment. If you go straight to Mars and something goes wrong it's at least a six month journey back home. That's a long flight in an emergency.

  6. It would make sense if possible by Bathroom+Humor · · Score: 2

    Just building a launchpad and fuel storage infrastructure on the moon does make more sense than blasting off from earth every time. The less gravity that the platform has, the more efficient it is to lift off from it.

    I guess it might technically be cheaper to launch if you assemble ships using a space ladder and launch from that orbit... but it would likely be easier to make a moon base.

    The question then becomes, how to make the fuel on the moon? They could send millions of tons of fuel up there waiting to be spent, but that would cost a huge amount of money anyway. So I'm not sure if there would actually be any savings overall.

    1. Re:It would make sense if possible by david_thornley · · Score: 1

      TFA quickly says it should be possible to make fuel locally, without many details. Sending lots of fuel from Earth to the Moon would be counterproductive. Easier to send it from Earth to low Earth orbit and do the refueling there.

      --
      "When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
    2. Re:It would make sense if possible by ShanghaiBill · · Score: 1

      Just building a launchpad and fuel storage infrastructure on the moon does make more sense

      No, don't build a launchpad. The moon has no atmosphere, so you can use a mass driver instead. A mass driver is far more efficient than launching rockets.

    3. Re:It would make sense if possible by ShanghaiBill · · Score: 3, Informative

      TFA quickly says it should be possible to make fuel locally, without many details.

      There is water in the moon's polar craters. It can be separated into H2 and O2 using electricity from PV solar panels.

    4. Re:It would make sense if possible by techno-vampire · · Score: 4, Interesting

      Another good thing about that way of doing it is that by the time you've built the fuel-making plant, you've had to learn how to live there without constant resupply of air and food. Once you've done that, you have the beginnings of a colony there, and you can use what you've learned once you reach Mars. And, building a self-sustaining base on Mars will be easier than on the Moon because Mars has an atmosphere, making pressure issues simpler and giving you some protection against the smaller micrometeorites.

      --
      Good, inexpensive web hosting
    5. Re:It would make sense if possible by CCarrot · · Score: 1

      Another good thing about that way of doing it is that by the time you've built the fuel-making plant, you've had to learn how to live there without constant resupply of air and food. Once you've done that, you have the beginnings of a colony there, and you can use what you've learned once you reach Mars. And, building a self-sustaining base on Mars will be easier than on the Moon because Mars has an atmosphere, making pressure issues simpler and giving you some protection against the smaller micrometeorites.

      This!

      The first thing that jumped out at me from this summary is "OMG, to do this we'd have to have a manned structure on the moon!"

      How awesome would that be? And where do I sign up to be a gas jockey on the moon?!?

      --
      "I love animals! Some are cute, others are tasty, what's not to like?" - Betsy Schroeder, Jeopardy contestant
    6. Re:It would make sense if possible by CanadianMacFan · · Score: 1

      Unless it's all automated.

    7. Re:It would make sense if possible by DanielRavenNest · · Score: 3, Insightful

      Electromagnetic catapults are overkill for small amounts of mass launch from the Moon. If you need a million tons a year, they are great.

      For small amounts, a centrifugal catapult works fine. Rotor arm of high strength material, electric motor, and solar arrays to power it. The Moon is small enough that you can reach orbit velocity with ordinary materials. If you have two rotors, you can regeneratively slow down one to reload while spinning up the other, with little energy wasted.

      Math on rotor arm:

      Lunar orbit velocity + a bit so it misses mountains and can be collected = 1700 m/s.
      Assume 1000 g's at the rotor tip. You are launching rock, it doesn't care. Acceleration = v^2/r. Solving for r we get 290 meter radius. Acceleration varies linearly from center to tip, so is 500 g's average x 290 meters = 144.5 g-km.

      High strength carbon fiber has a characteristic strength of 361 g-km, but you don't design to ultimate strength. A reasonable value is 150 g-km, giving a rotor taper of about 3, and mass ratio of 6 because it has two arms. You want the rotor to be balanced so it doesn't jerk the axle around, which means you also throw a rock backwards into a hill. That's inefficient, but there is no lack of rocks.

      A modern solar array can supply the 1.44 MJ/kg to launch it's own mass of rock in 2.25 hours. Since we throw an equal mass into a hill, we get 4.5 hours, and allowing for inefficiencies, let's assume 6 hours. The Sun is shining half the time, and a solar array lasts ~15 years in space. So a solar array can power launching 11,000 times it's own weight before it wears out. Add whatever the rotors, motors, and other infrastructure you need (rock loaders and gatherers) and you are till way ahead.

    8. Re:It would make sense if possible by DanielRavenNest · · Score: 3, Funny

      Remote controlled from orbit, it's the only way to be sure :-).

    9. Re:It would make sense if possible by Required+Snark · · Score: 2

      Enlist the pumpkin chuckers.

      --
      Why is Snark Required?
    10. Re:It would make sense if possible by tomhath · · Score: 1

      That doesn't mean it's a good idea.

    11. Re:It would make sense if possible by blindseer · · Score: 1

      Please recompute with a nuclear reactor.

      That avoids the need to shutdown when night falls. Also likely a much longer than 15 year lifespan before it wears out, more like 50 years.

      --
      I am armed because I am free. I am free because I am armed.
    12. Re:It would make sense if possible by RockDoctor · · Score: 1

      And, building a self-sustaining base on Mars will be easier than on the Moon because Mars has an atmosphere, making pressure issues simpler and giving you some protection against the smaller micrometeorites.

      The micrometeorite protection may well be significant. But the pressure difference? Surface pressure on Mars gets as high as 0.9kPa, which is still less than 1% of the Earth's surface pressure.

      You'd get far more benefit in terms of reducing pressure loads by recruiting and training Andean silver miners and Nepali Sherpas for your crew instead of sea-level weaklings.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
  7. Use the moon for all launches by surd1618 · · Score: 2

    It would be ideal to use the moon as a platform for all satellite launches, supposing we can find the raw materials there to make metals. There's enough water and oxygen for humans, and enough silicon to make photovoltaics. Electronics and rare or hard-to-purify materials could be imported from Earth. Fuel could be made using the PVs by reduction of water or other reactions. Once we have a good lunar base, putting satellites in orbit around the Earth or sending ships to Mars will be far more efficient and less polluting and wasteful. And we could use toxic or radioactive rockets that we can't launch from Earth, with fluorine as an oxidizer, or fission.

    1. Re:Use the moon for all launches by surd1618 · · Score: 1

      Oh, also, we could make the best optical telescope ever on the far side of moon.

    2. Re:Use the moon for all launches by david_thornley · · Score: 1

      To launch a satellite from the Moon, it has to start on the Moon. This means that either it was built on the Moon from locally available materials (which I think unlikely) or it was sent from Earth. Sending a satellite to the Moon is more expensive than putting it in Earth orbit.

      It's going to take a lot of industrial capacity in space to make that practical.

      --
      "When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
    3. Re:Use the moon for all launches by CCarrot · · Score: 2

      ...pointing at the sun for two weeks out of every month.

      ...thereby delighting the solar physicists...

      --
      "I love animals! Some are cute, others are tasty, what's not to like?" - Betsy Schroeder, Jeopardy contestant
  8. Martian refinery? by psyclone · · Score: 1

    If you can extract resources from the moon to create fuel, perhaps you can do the same on Mars? Then the lunar refinery only needs to produce enough fuel to get to Mars, and the martian refinery can produce the return trip fuel.

    1. Re:Martian refinery? by ShanghaiBill · · Score: 1

      the martian refinery can produce the return trip fuel.

      Why do you need to return? There is no reason to return robots. We shouldn't send people until we are ready to establish permanent colonies. Then there is no need for a return trip. Eliminating the return can drastically cut the cost.

    2. Re:Martian refinery? by DanielRavenNest · · Score: 2

      You are starting to get the idea, but it's incomplete. Mine everywhere. Near-Earth asteroids, our upper atmosphere (scoop mining), the Moon, Phobos, Mars. Each place produces fuel and supplies to get to the next place. You develop mining and processing tech once in general, and use it everywhere. In reality, we already know a lot about mining and materials processing on Earth, that's where all our stuff comes from. What we need is to adapt what we know to the particular locations and what materials are found there.

  9. Old idea by Livius · · Score: 1

    I really don't want to minimize the engineering problems they're trying to solve, but a refuelling station is not a new idea. Thousands of years ago there were rest stops on courier routes.

    1. Re:Old idea by Megane · · Score: 1

      Thousands of years ago they didn't have to worry about delta-vee and gravity wells. Orbital mechanics isn't as easy as having horses pull wagons.

      --
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    2. Re:Old idea by Livius · · Score: 1

      True, but Bronze Age technology had its own logistical challenges.

  10. Step 1 by slick7 · · Score: 1

    Before you build the upper floors of a house, you need the foundation. Pioneer endeavors to other planets should begin with a foundation of ongoing commerce between Earth and the Moon. This reeks of another " trip to the Moon " , once you go, been there, did that; and now for the next campaign rally .
    A myopic vision is compounded by a short attention span.

    --
    The mind conceives, the body achieves, the spirit manifests.
    1. Re:Step 1 by Thiez · · Score: 1

      Commerce? Are you mad? What could the moon possibly produce that, after the cost of moving it from the moon to the earth, couldn't be produced for a fraction of the cost here on earth?

    2. Re:Step 1 by Talderas · · Score: 1

      Moon juice

      --
      "Lack of speed can be overcome. In the worst case by patience." --Znork
  11. Re:no by psyclone · · Score: 1, Troll

    Agreed. Everyone knows robots are the future of space exploration, not fragile meat bags.

  12. It might be worth it --- eventually by yokem_55 · · Score: 2

    The problem with any space based mining/resources operation is that competition from just launching from Terra Firma doesn't go away. Let's say that SpaceX can get a fully reusable BFR flying regularly, putting 100 metric tons to leo on every launch at a vastly lower cost. Would it still worth the huge capital expenditure to develop space based resource mining/extraction to reduce the amount of mass that needs to go up form Earth? Maybe eventually -- the rocket equation is cruel, but we are no where near the limits of what we can do with technology on a $$$/kilo delivered to Mars.

    --
    ...and IN SOVIET RUSSIA, beowulf clusters imagine 1, 2, 3 profit!!!! jokes made out of YOU!!!
    1. Re:It might be worth it --- eventually by 0123456 · · Score: 1

      Let's say that SpaceX can get a fully reusable BFR flying regularly, putting 100 metric tons to leo on every launch at a vastly lower cost. Would it still worth the huge capital expenditure to develop space based resource mining/extraction to reduce the amount of mass that needs to go up form Earth?

      The more cheaply you can put things into orbit, the more cheaply you can build infrastructure in space. Which we have to do, if we want to get off this planet for good.

      But, whatever the cost, I really can't see much of a case for funding all that infrastructure to launch one mission to Mars. It only makes sense if you're going to be flying a lot of spaceships around the solar system.

    2. Re:It might be worth it --- eventually by DanielRavenNest · · Score: 1

      > Would it still worth the huge capital expenditure to develop space based resource mining/extraction to reduce the amount of mass that needs to go up form Earth?

      Yes, because asteroid mining plus self-bootstrapping manufacturing systems leverages the launched mass by hundreds to one. Bootstrapping means sending core machines, grabbing some metallic asteroids, and machining them into parts for more machines, like chemical processing units. Keep doing things like that till you have a whole factory. Asteroid mining has a mass return ratio of about 200:1 on the mass of the mining tug. If the core machines are the same mass as the tug (30 tons), your net return is then 100:1.

      Also, a BFR, or any rocket, doesn't fly efficiently unless you are launching at least 6-20 times a year. There currently isn't 600-2000 tons of annual launch traffic, and certainly not in 100 ton loads. You only need a BFR if you are doing something like colonizing Mars, in which case the 100:1 leverage is very useful, because propellant to get to Mars and stuff they need once they get there is a lot more traffic than we have today.

      Also, if it's fully reusable, and only flying 20 times a year, your aren't building many new BFRs each year, so your production line for them isn't very efficient and cheap. Space mining can reduce the size of your launcher and optimize the launch and production rate so the whole system is running at optimum cost and efficiency

  13. How do we get one by rgmoore · · Score: 1

    Yeah, it would be great to be able to launch fuel from the moon, but how easy is it to get a fueling station there? My intuition is that it would take a lot more resources to build a moonbase capable of sending up the fuel for trips to Mars than it would to just ship everything for the trip to Mars directly from the Earth. This approach only makes any kind of sense if you plan on going to Mars a lot- or if you're just looking for a convenient excuse to build a moonbase.

    --

    There's no point in questioning authority if you aren't going to listen to the answers.

    1. Re:How do we get one by CanadianMacFan · · Score: 1

      I would hope that we are not going to limit our exploration of the solar system to a couple more trips to Mars and say we're done. Let's use this to go the Moon, Mars, and anywhere else many times. It doesn't have to be manned missions. Send probes, robots, and any other missions. Just think how much cheaper science missions to the other planets could be. Maybe it would make something like the James Webb telescope but with the capability to come back to Earth orbit for repairs and upgrades possible if fuel was inexpensive enough.

    2. Re:How do we get one by Ol+Olsoc · · Score: 1

      Yeah, it would be great to be able to launch fuel from the moon, but how easy is it to get a fueling station there? My intuition is that it would take a lot more resources to build a moonbase capable of sending up the fuel for trips to Mars than it would to just ship everything for the trip to Mars directly from the Earth. This approach only makes any kind of sense if you plan on going to Mars a lot- or if you're just looking for a convenient excuse to build a moonbase.

      A sensible plan that we know would work is launch and assembly in earth orbit. We can get everything needed from earth.

      I don't have any issues with the concept of building a ferry - in the manner of the way we built the ISS, in earth orbit, then having the mars landers and other needed logistics rendezvous with it. But building and operating a moon base, would at best add years to the schedule, and at worst, bring the program to it's knees and kill it off I still haven't seen the final numbers on exactly how much water there is to exploit on the moon, so until that number is known, its hardly even worth the argument of producing fuel at a lunar base. We could spend years arguing, and find out that there just isn't enough raw materials on the moon.

      Is the technology for creating fuel on the moon mature and worked out? Certainly if the raw materials were limited in supply, any surprise inefficiencies in the production will kill the program.

      How much extra logistics will be needed to operate the lunar base? How much fuel to get the lunar produced fuel to lunar orbit?

      There's simply too many things that need to be "just so" to even consider this option, outside of people just wanting to argue about stuff.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
  14. What kind of fuel??? by Zobeid · · Score: 1

    Please tell me we're not talking about chemical rockets here? A nuclear rocket is the most sensible way to get to Mars, as it can reduce the flight time to a third of what's required with chemical fuel. Then everything becomes vastly easier. The life support and other supplies are greatly reduced. The crew's exposure to radiation and microgravity is greatly reduced. We developed nuclear rocket engines in the 1960s. It's time to use them.

    Now, if you want to mine thermal reaction mass on the Moon, sure. . . Why not? The Moon would be a great proving ground for equipment and techniques that would be used on the later Mars mission.

    1. Re:What kind of fuel??? by DanielRavenNest · · Score: 1

      > We developed nuclear rocket engines in the 1960s. It's time to use them.

      Solar-thermal rockets have the exact same exhaust velocity as nuclear-thermal, because both heat hydrogen as hot as you can get it before the equipment melts. Solar-thermal avoids all the political and public hysteria issues about nuclear, and also the crew radiation issues nuclear adds (beyond the space radiation issues that already exist anyway).

      But the best answer is a split mission, using electric thrusters that are 3-5 times as fuel-efficient as nuclear-thermal for anything that's not time-sensitive. That includes taking your crew habitat and main ship from Earth orbit to just shy of lunar flyby and orbit injection, and any pre-positioned cargo that goes ahead of the crew. The crew take a fast capsule to meet the main ship and go on from there. Once the crew are on-board, you use faster propulsion, because you don't want to eat up their time.

    2. Re:What kind of fuel??? by InfiniteLoopCounter · · Score: 1

      Solar-thermal rockets have the exact same exhaust velocity as nuclear-thermal, because both heat hydrogen as hot as you can get it before the equipment melts.

      I don't know what planet you are from, but wikipedia lists Solar-thermal rockets as currently theoretical and very slow. There is no way that a typical nuclear rocket (pushed forwards by essentially a controlled nuclear explosion) would have similar thrust to a solar-thermal rocket. Solar-thermal rockets would be much slower than chemical rockets (the exhaust would come out faster, but is pretty weak). Over long periods, once already in space, could be quite decent though. Getting off the ground against gravity would still likely require alternate propulsion for solar-thermal rockets carrying any cargo at all.

      I would think that the shape of the exhaust would determine the easiest way for an explosive thrust to escape and, along with the impulse time, is just as crucial as the type of material that contains it in terms of how much heat it can handle.

  15. efficiency by quenda · · Score: 2

    If you want an "efficient" mars mission, the last thing you want is to send people. That sort of thinking is just stuck in the past, like old science fiction whose idea of an automated car was one driven by a robot. They are successfully reducing launch mass by using smaller robot probes. Miniaturisation is the key. Exploration and research is good, but does not need bodies in a can. If you want to establish a colony, do it somewhere far cheaper and more sensible, like the bottom of the Pacific.

    1. Re:efficiency by Ol+Olsoc · · Score: 1

      If you want an "efficient" mars mission, the last thing you want is to send people. That sort of thinking is just stuck in the past, like old science fiction whose idea of an automated car was one driven by a robot. They are successfully reducing launch mass by using smaller robot probes. Miniaturisation is the key.

      Robots are good and all, but they have one big problem.

      With human presence in space, I'll suppport almost any amount. With robot only? $0.00 dollars.

      Many are just like me - and I would campaign actively to make sure that no money figure happens.

      Robot lovers have to realize that they are the tail, not the dog. I like science. I like human exploration. When both happen, it's magic.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
    2. Re:efficiency by DanielRavenNest · · Score: 1

      Robots vs. Humans is a false dichotomy. For example, we can park the humans on Phobos, and remote-control the first set of robots in real-time, because the signal delay is less than 100 ms. On Phobos they can mine the local rock for supplies and fuel to land, and head down once the robots have prepared a flat landing pad, and dug a hole for the crew habitat (so it can be protected from radiation). Use the robots as grunt labor to get the site prepared, then send the people.

    3. Re:efficiency by KeensMustard · · Score: 1

      Many are just like me

      Umm. No.

      Most people find the idea of other people floating around in space making lame jokes a bit, well, lame. Space is unpleasant and empty, and really if everything i going right, it makes for boring viewing. That's why the apollo missions were cancelled. Everybody lost interest by the third one.

      Robot lovers have to realize that they are the tail, not the dog. I like science. I like human exploration. When both happen, it's magic.

      Robots are drifting on Mars like whiny 90's yuppies, lassooing and riding comets like rodeo stars, dropping in on Titan like an annoying aunt, flashing past Pluto like overenthusiastic paparazzi. Robots have left the solar system. Meanwhile humans clean the toilet on the space station.

      Robots aren't going to wait for your permission to go to space: sorry.

    4. Re:efficiency by Applehu+Akbar · · Score: 1

      "With human presence in space, I'll suppport almost any amount. With robot only? $0.00 dollars."

      That's why exploration beyond the moon is going to be robots first (already underway) followed by private-sector humans when robots have brought down the costs and the way is prepared for them.

    5. Re:efficiency by Applehu+Akbar · · Score: 1

      "Well, if you don't care about getting humans out then why even send robots? It's even more efficient to just build better telescopes on Earth."
      Here's the bad news about building large telescopes on Earth:
      http://dgrnewsservice.org/2015...

      The good news is that there are no liberals in space.

    6. Re:efficiency by Ol+Olsoc · · Score: 1

      That's why the apollo missions were cancelled. Everybody lost interest by the third one.

      Apollo had done what it set out to do. The reason it was canceled, aside from that, was to free up money for another manned project, the Shuttle, which first started studies in 1968.

      Apollo 20 mission was cancelled to free up a Saturn rocket to launch Skylab - another manned mission to earth orbit, in an early spce station effort.

      Budget considerations had also only built 15 Saturn 5 rockets, so the extra missions were never really seriously planned.

      Your revisionist history is based on popculturish news media self aggrandizement thinking that because they - the media - had lost interest in covering moon launches, that everyone had.

      Robots are drifting on Mars like whiny 90's yuppies, lassooing and riding comets like rodeo stars, dropping in on Titan like an annoying aunt, flashing past Pluto like overenthusiastic paparazzi. Robots have left the solar system.

      And that is damn awesome. I love that kind of stuff. But unless there is a human presence off earth, there isn't much point ot it, other than we'd just like to knowabout stuff. Worthy? Yes. The sole focus - no.

      Many humans have a deep seated need and desire to explore. Others are reverse terra firma types - the more firma, the less terra.

      Robots aren't going to wait for your permission to go to space: sorry.

      And they will have my blessing. As long as there is a manned presence there also.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
    7. Re:efficiency by Ol+Olsoc · · Score: 1

      "With human presence in space, I'll suppport almost any amount. With robot only? $0.00 dollars."

      That's why exploration beyond the moon is going to be robots first (already underway) followed by private-sector humans when robots have brought down the costs and the way is prepared for them.

      Works for me.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
  16. Re: no by cyber-vandal · · Score: 3, Insightful

    There's always dull people on stories like these. You boring bastards are always there holding the doers back with your pathetic can't do attitude.

  17. -Make fuel- on the moon? by yusing · · Score: 1

    Awfully light on the kinds of fuel that might be made. Pipe dream, but where's the pipe? The moon may or may not have much water ice. Apart making H and O (requiring large storage tanks ... that have to come from Earth) ... what else is there? Where are the BIG CARBON deposits on the moon? No C, no hydrocarbates. Going to bring the carbon from Earth?

    This idea might have come from a 12-year-old, so far as the article is concerned. Except that a 12-year-old would probably be more practical.

    --

    "You must try to forget all you have learned. You must begin to dream." -- Sherwood Anderson

    1. Re:-Make fuel- on the moon? by Ol+Olsoc · · Score: 1

      Awfully light on the kinds of fuel that might be made. Pipe dream, but where's the pipe? The moon may or may not have much water ice. Apart making H and O (requiring large storage tanks ... that have to come from Earth) ... what else is there? Where are the BIG CARBON deposits on the moon? No C, no hydrocarbates. Going to bring the carbon from Earth?

      This idea might have come from a 12-year-old, so far as the article is concerned. Except that a 12-year-old would probably be more practical.

      Read the article. It's very precise calculations built upon a foundation of a guess.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
  18. AFV - needed.. by willy_me · · Score: 1

    AFV - autonomous fuel vehicle. Why send all the fuel with the astronauts? Send multiple smaller fuel tanks ahead of time and have them go into orbit around Mars. This should greatly reduce the risk of such a mission. Hell, do not send astronauts until you have first verified that 150% of the fuel required has already been successfully put into Mars orbit. Then when humans do go to Mars (if it ever happens), first have then sit in orbit using a robotic workforce to construct whatever planet based infrastructure they require. Only when everything is done should humans step foot on Mars.

  19. Eureka! by Ol+Olsoc · · Score: 2
    All we have to do to make this very smart study 100 percent true, is in addition to the fuel production plant on the moon, as this awesome gizmo that allows us to get all this shit to the moon for free.

    So Have these geniuses calculated exactly how much water is on the moon? And how do they know? Enough to fuel every lanuch to mars - plus the water needed by the operators?

    What is the specific tonnage of water on the moon? Maybe that is important. Or maybe we can send water form earth there and still save money.

    Every single MOON FIRST! scenario seems to need a "Here sumpin cool happens" placed right in the middle of the equation, and without it, the whole thing fails.

    So instead of using present technology to develop and go to Mars, we're going to embark on a hundred year project to just get started.

    Anyhow, it was quite cool reading the precise calculations based upon a wild-ass guess.

    --
    The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
  20. Fuel cost is not the issue its the rocket by n2hightech · · Score: 2

    Fuel is a small cost of a space launch. Only about $250,000 per low earth orbit launch is fuel. The big cost of space flight is the throw away rockets. Going to extreme measures to save fuel is not a wise use of resources. With the boost capability of the Falcon 9 it would take maybe 100 flights to carry the amount of fuel and resources needed for a flight to Mars and back. Assuming 100% reusability the cost to carry the fuel to orbit is only $25million. Developing and building a refueling station on the moon and manning it would probably cost many billions of dollars. Spending billions to save millions does not make much sense. The thing that will make space travel cost reasonable is getting to that 100% reusability and long operating life. A rocket with 120 flights to orbit would only have 40 hours of run time on it. Current Jet engines can run for thousands of hours between rebuilds. The Air frame can go much longer than that. Once we get rockets and engines with those same types of run times and perfect vertical return landings flying to space will not cost much more than the fuel and it is cheap.

  21. Deja-vu by Megane · · Score: 1

    Maybe not a dupe, but definitely deja-vu...

    http://science.slashdot.org/story/15/09/26/0050245/why-nasas-road-to-mars-plan-proves-that-it-should-return-to-the-moon-first

    --
    #naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
  22. Re: We have top men investigating this. by murdocj · · Score: 1

    Wombyn, not womyn, you patriarchal fool.

  23. Obvious idea is obvious by kheldan · · Score: 1

    Gee whiz, all that infrastructure to be built on the Moon would require lots of personnel to construct, maintain, and operate; sounds to me like having a permanent colony on the Moon would be the first step in that process..

    ..which is what I've been saying for years now, and more than once here on Slashdot. Come on MIT, try to keep up, will you please?

    --
    Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
    1. Re:Obvious idea is obvious by kheldan · · Score: 1

      I have a hard time taking someone seriously who uses "ain't" in a non-ironic manner. Now shut up and drink your Budweiser, and stop beating your wife.

      --
      Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
  24. Yes, the Moon first! by Anonymous Coward · · Score: 1

    We need a permanent international Moon base much like the ISS before we even start planning for Mars. Make all our mistakes, learn all our lessons on the Moon where it would be MUCH cheaper and closer to Earth. Once the Moon base becomes just another standard science base (like Antarctica & the ISS), then, and only then, can we prepare for Mars.

    Going to Mars without learning from a Moon base is a bit like entering a marathon without ever having exercised.

  25. Re:no by DanielRavenNest · · Score: 2

    Self replicating, factory and habitat-building robots. The meat bags can show up once everything is ready for them.

  26. Article authors are all looking at it wrong. by slashdot_commentator · · Score: 1

    Most likely, the authors are envisioning a future Mars mission being propelled by chemical rockets. And that would requires oxygen (or water as the storage medium). But that's all wrong. The true rational approach would be to develop ION propulsion, which does not require oxygen, and does not require a lot of propellant. So assuming the future manned Mars mission is attempted, it wouldn't be using chemical rockets, which means not a lot of propellant mass needs to be moved into space from Earth.

    If there are metal deposits to be mined from the Moon, that would save a lot of mass if the superstructures could be manufactured from space. Right now, no one believes there are such deposits readily available, so that is wishful thinking.

    Really, the only integral material that could be produced from the Moon would be water, which would be indispensable for sustaining the crew, making available an emergency supply for oxygen, and being a component of a radiation shield.

    As I see it, there are only two critical aspects of developing a Mars mission. First would be that ION drive, so that the mission can be completed in less than a year, which requires better propulsion than chemical rockets. Second would be the scheme used to shield the crew from radiation. If they can't survive a solar flare, there's no point in even trying to go to Mars. Then it makes sense to figure out just how much mass is required.

    If lots of water is needed for a Mars mission, then the design of a robot factory to produce water on the Moon makes sense. If not, then may as well eat the cost of a Mars mission launching water from Earth, rather than designing a robot factory for the Moon.

    --
    There is no America. There is no democracy. There is only IBM and AT&T and DuPont, Dow, General Electric, and Exxon
  27. Re: no by cyber-vandal · · Score: 2

    Much of the progress of the human race has come from wide eyed dreamers. Bores like yourself have nothing to offer.

  28. Space: 1999 . . . take the Moon to Mars! by PolygamousRanchKid+ · · Score: 1

    Is nobody here old enough to remember Space: 1999? In that British science fiction series, nuclear waste stored on the Moon mysteriously ignited and took the Moon on a wild and wacky romp through the universe.

    So, let's get on it, and plan a mission to take the Moon to Mars!

    A paper on this idea would definitely win an IgNobel, at least.

    --
    Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
  29. Re: We have top men investigating this. by murdocj · · Score: 1

    Heh... happily, I'm getting plenty. But that was too easy.

  30. Re:-- JEW nasa fraud by Applehu+Akbar · · Score: 1

    Meanwhile in our world, Walter White was a fictional character while World War II really happened.

  31. Re: - jew fake right left - by Applehu+Akbar · · Score: 1

    I liked you better when you were just ranting away about "space nutters."

  32. Re:no by Applehu+Akbar · · Score: 1

    You may be closest to the actual long-term scenario.

  33. Not to mention by argStyopa · · Score: 1

    Not to mention that there are precisely 2 points on the moon that have both a) a constant line of sight to Earth, and b) constant line of sight to the sun (ie power): the poles.
    Whatever nation occupies those poles with its stations will have a strategic advantage over all latecomers to the regular use of near-earth space.

    --
    -Styopa
  34. Re: no by blind+biker · · Score: 1

    I very much agree. There's a lot of people with knowledge, will and means - and a bit of madness, but somehow we are supposed to listen to can't-doers. Robots are nice, they can collect some scientific data. Humans are harder to put on planets and moons, but it's way more FUN! As a bonus, humans aren't too shabby at doing research on-site. As another bonus, putting humans on moon and mars will bring about some technical innovations that we can't even foresee right now.

    --
    "The agriculture ministry is not in charge of Gundam" - Japanese ministry official.
  35. Nuclear power is the key here by blindseer · · Score: 2

    There is also fuel in the form of uranium and thorium.

    Using solar power as you propose, spanning the moon with power lines so that there is always light shining on the panels, would be an exceedingly difficult and costly way to produce power. To get the oxygen and hydrogen from the lunar surface you'd already be digging up the rock and processing it. What do you do with all the stuff that isn't oxygen and hydrogen?

    From that rock you are going to get a lot of iron, aluminum, silicon, magnesium and other elements useful for building material. There's also a lot of calcium, potassium, sodium, and other stuff useful for supporting life. After all of that is extracted you are going to have piles of uranium and thorium, while also useful as a building material it would be much more useful as a power source.

    Building a power line that goes around the moon would be equivalent of building one across Russia. Granted it only has to go halfway around to work that just means going halfway across Russia, still a long way. All of that aluminum used to make that wire would be more useful in building other things, like tanks for the hydrogen and oxygen you'd be making from your nuclear powered fuel factory.

    Unlike on Earth the disposal of any nuclear waste is not an issue. The entire surface of the moon is bombarded with radiation from space, no place is safe from radiation so anything additional from the reactors is trivial. After you've dug a hole to get your oxygen and hydrogen from the rocks then dump in your trash, including the radioactive stuff.

    Actually there's probably a bunch of valuable stuff in the fission products, best not to throw that away.

    --
    I am armed because I am free. I am free because I am armed.
  36. Why solar power? by blindseer · · Score: 1

    Why do we have this fascination with solar power on the moon? With the exception of a small area near the poles the sun sets on the moon for weeks at a time. Something has to power your moon base when the sun goes down. I suppose the power could be stored but that is going to be very expensive.

    Use nuclear power, it's not like there's a shortage of uranium and thorium on the moon.

    If we can find enough hydrogen and oxygen to make fuel, and enough silicon to make solar panels, then finding fuel for a fission reactor is going to be trivial by comparison. Oh, and fusion reactors are only a dream right now so don't suggest helium-3 as a viable fuel.

    --
    I am armed because I am free. I am free because I am armed.
  37. Really? by BubbaJonBoy · · Score: 1

    It took MIT to state the obvious?

  38. Re:Obvious cover-up by MachineShedFred · · Score: 1

    I was actually going to post that I totally did this in KSP - Minmus (the tiny second moon of Kerbin) is a great place for a fuel stop when heading to the farther reaches of the Kerbol system because it only takes ~300 dV to get back to orbit from being landed. So you launch a mining station first, and some hardware to undock from it, lift a large fuel tank into orbit where it can rendezvous with your deep space vessel and transfer fuel, and then deorbit back to the mining station for reuse.

    Works like a champ, as it takes a good chunk of dV to get into Kerbin orbit, and I'd like to have that back before leaving.

    --
    Slashdot still doesnâ(TM)t support Unicode after it was added to the HTML standard in 1997.