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Mars Moon Space

Going To Mars Via the Moon (mit.edu) 151

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.
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Going To Mars Via the Moon

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  • by 140Mandak262Jamuna ( 970587 ) on Friday October 16, 2015 @04:28PM (#50746793) Journal
    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.
    • 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.

  • by Anonymous Coward

    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.

    • Re: (Score:3, Interesting)

      by Anonymous Coward

      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 efficien

      • 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?
        • Re:another idea (Score:5, Interesting)

          by DanielRavenNest ( 107550 ) on Friday October 16, 2015 @10:14PM (#50747977)

          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).

          • by tomhath ( 637240 )
            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.
            • 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.

      • by tomhath ( 637240 )
        Energy efficient perhaps, but silly. It is so much easier to manufacture the fuel on Earth and launch it even if it does require a bigger booster.
  • by turkeydance ( 1266624 ) on Friday October 16, 2015 @04:42PM (#50746853)
    the rest is just commentary.
    • 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....

      • 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.

      • 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 nev

    • by fsagx ( 1936954 )

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

    • 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.
      • 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.

  • just go somewhere!!! (Score:5, Interesting)

    by bkmoore ( 1910118 ) on Friday October 16, 2015 @05:04PM (#50746943)
    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.
    • by ShanghaiBill ( 739463 ) on Friday October 16, 2015 @05:48PM (#50747167)

      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?

      • by CanadianMacFan ( 1900244 ) on Friday October 16, 2015 @07:57PM (#50747585)

        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.

  • by Bathroom Humor ( 4006829 ) on Friday October 16, 2015 @05:04PM (#50746945)

    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.

    • 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.

    • 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 [wikipedia.org] instead. A mass driver is far more efficient than launching rockets.

      • by DanielRavenNest ( 107550 ) on Friday October 16, 2015 @10:37PM (#50748029)

        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.

    • by techno-vampire ( 666512 ) on Friday October 16, 2015 @06:14PM (#50747277) Homepage
      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.
      • 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?!?

      • Unless it's all automated.

      • 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

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

    • 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 fissio

  • 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.

    • 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.

    • 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 ar

  • 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.

    • by Megane ( 129182 )
      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.
  • 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.
    • by Thiez ( 1281866 )
      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?
  • by yokem_55 ( 575428 ) on Friday October 16, 2015 @05:46PM (#50747155)

    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.

    • by 0123456 ( 636235 )

      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.

    • > 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. Ast

  • 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.

    • 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

    • 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

  • 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.

    • > 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

      • 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 [wikipedia.org]. 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 [wikipedia.org] (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 gr

  • by quenda ( 644621 ) on Friday October 16, 2015 @06:26PM (#50747317)
    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.
    • 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.

      • 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.

      • 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 le

        • 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

      • "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.

        • "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.

  • 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.

    • 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.

  • 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 infras
  • by Ol Olsoc ( 1175323 ) on Friday October 16, 2015 @08:16PM (#50747651)
    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.

  • 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 mo
  • 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?
  • by Anonymous Coward

    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.

  • 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

  • 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.

  • It took MIT to state the obvious?

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