SpaceX Mars Planned Colonization Fleet Compared to American Airline Passenger Fleet

45 thoughts on “SpaceX Mars Planned Colonization Fleet Compared to American Airline Passenger Fleet”

1. I don’t think they’ll need bigger Starships for some time. One Starship could probably haul as many as 500 people to LEO and transfer them to a transit ship that just stays in space but has a lot more room and doesn’t lug along fins and aerodynamic hull that aren’t needed in space.

   With 500 per transit ship, you’d only need 1/5th as many (much bigger in volume) transit vehicles. Land people on the other end using Starships that stay at Mars.

2. Can’t really argue with that.

3. I think you are missing the point.

   The point is not to start with an existing amount of money, and an existing job to do, and end up with the job done and the least amount of money spent and least amount of CO2 in the atmosphere.

   That would be good if it was the point, but that’s not the point.

   The point is to start with an existing amount of money, and an existing job to do, and end up with the job done and a fancy schmancy CO2 removal scheme that you can tweet about and show on your website so that people feel good about you and buy your cars and lean your way when various government enquiries and legal decisions are made about any of the 147 different business enterprises that you are involved in.

4. I agree with the overall description, but still favor starting at the Moon. But Musk rockets make much possible almost too unexpectedly to absorb. I think I’ve noticed an important difference between Musk/Mars and Bezos/O’Neill that may trigger confused assumptions. Musk is concerned with getting people to Space/Mars, with the tech to do so a bother. O’Neill wants to get everything in Space, “an expanding tech civilization”, with people eventually but starting with Space Solar. O’Neill favors the current robot refueling (and then lunar sourcing) of non-human sats, then grow to also refuel for humans too, for example. This all has near term cash rewards, but is not a human Space project, esp at first. An operating system for Space, more than just a Space program.

5. The Mars fuel plants can be set up on the first Mars trip, just like they can be set up on the Moon on the first Moon trip – provided the needed engineering homework is done beforehand. That’s the nice thing about having a 100+ ton payload capacity.

   Realistically, either of these can happen first. But by the time they’ll be sending hundreds of ships per trip, both may be in place, maybe along with orbital fuel depots. I doubt they’ll be sending hundreds of ships in the first few rounds.

   The part that didn’t fit in my previous reply: Mars and the Moon and O’Neill aren’t mutually exclusive (despite historical attitudes to the contrary). Do all of them. Elon Musk can focus on Mars while others use his rockets for the Moon and O’Neill.

6. Neglecting the other costs, that comes out at $90K per launch for just the methane (based on 4500 tons methalox). Elon Musk recently stated a (marginal?) launch cost of $2M, so yes, that wouldn’t be much in comparison.

   Nevertheless, selling the renewable electricity and buying the fossil methane it replaces would give similar environmental benefits at a fraction of the cost. Considering the (in)efficiency and profit margin of fossil fuel power plants, you might even come out with a profit (at least if you ignore the cost of the renewable electricity, which you’ll need either way).

   edit: On further inspection, bulk natural gas is ~150-200 $/ton, if I got the unit conversion right. So maybe it wouldn’t be that much cheaper. In this context, your $100/ton CO2 capture cost looks surprisingly low.

7. You do have to fly enough back so people feel comfortable that return trips will be available.

8. Direct air capture of CO2 would be about $100/tonne, using tech from Carbon Engineering or Climeworks. Then there’s the cost to turn it into methane. Fuel might cost several times as much that way but that still adds up to very cheap launch.

9. So, just use lunar derived water/C, processed in Space, instead of re-fueling on the way, and until the Mars fuel plants are set up. Let the market decide. Realizing this will happen on the Moon/in Space long before on Mars is the key. Just dreaming of Mars will cause you to miss the stuff “at your feet”. Invest in lunar resources now, even if you later plan to go to Mars. O’Neill literally pulls the ground out from under most people’s planetonlyist assumptions.

10. What Dr Pat said. But to put it another way: a single Tesla is about 2 tons. So this would be the equivalent of 50000 Teslas. About a couple months’ work for Tesla’s factories at recent production rates.

    This would take some new production lines for the specialized hardware, but a lot of the components and supplies can be bought off-the-shelf, maybe with minimal modification.

11. If they’re not going to Mars, they won’t need the fuel there. If they are going to Mars they’ll have to mine for water anyway (for survival), and they’ll need power anyway (same). Once they have water and power, they’d only need some pumps, compressors, and a Sabatier reactor to make methalox. Yes, it adds some equipment and engineering costs, but relatively not much. Over time, it’s still cheaper than paying the delta-v and associated costs to transfer fuel or water from the Moon (not to mention that Mars likely has larger water reserves than the Moon, and almost definitely more carbon).

    If you had dedicated tankers that could be launched from the Moon with a mass driver, and could aerobrake and land on Mars with minimal fuel expenditure, that would make a little more sense. But that would add WAY more engineering and capital costs than making fuel on Mars. And you’d still have energy, time, materials, and operational costs operating the mass driver and sending stuff to Mars, which you could use elsewhere. And then you’d still need to send the tankers back somehow, otherwise you also have the cost of expendable tankers.

    I’m not saying “don’t make fuel from Lunar water”, but I am saying “use it wisely”. Lunar ISRU is useful, but it’s not a panacea. And don’t ignore local resources (such as Mars resources for Mars problems) just because you can do cool stuff on the Moon.

12. Yes, but see my reply to Jim Baerg. You’d get more bang for your buck just selling the renewable electricity and buying the fossil fuel it would replace (which ideally would be methane, but you could gassify coal or oil). Going fossil fuel -> CO2 -> (synthetic) fossil fuel is a lot less efficient.

    Though if the power plant actually pays you, that shifts things a little.

13. Atmospheric CO2 is very dilute on Earth (though not as dilute as many would prefer).

    But you don’t need to use atmospheric CO2. If there is a coal or gas power plant near by (I presume that Texas or Florida or somewhere in the USA has a couple of such plants) then you can get a concentrated CO2 stream from their exhaust stack. They may well pay you to take it.

14. So that would be the same tonnage of finished, high tech cargo that is daily loaded onto every single large cargo ship in the ports of Shanghai, Pusan, Horoshima and a dozen other similar places around the world.

15. The Physics *cost* of doing things O’Neill is less by far than on a planet. But we do need some starting effort to get there. Not doing Space Solar to solve global heating is the *cost* to be avoided.

16. Well, that is clear! Do the easy stuff first, collecting energy, beam to Earth. Use existing launched machines that need 1 g etc. only where launch cost plus machine *habitat* is FAR cheaper than adapting design to various degrees of Space enviro. Otherwise, invest in design and grow. Or, for even more complex stuff, continue launching the product itself. The goal is helping Earth thru Space, not just Mars.

17. If the fuel were made in Space, from raw stuff mass driven from the lunar poles, the energy and plant would have all of the advantages O’Neill points out. Everything is useful, some by the Mars people. Too much extra effort to do it separately on Mars, ie, “at the cost of additional engineering complexity.”

18. Elon said the first ones would stay on Mars.

19. I’m trying to imagine the scale of the on-Earth industry it would take to produce 100,000 tons of finished, hi-tech cargo every two years to load onto those 1,000 starships. Who would pay for it, and why? I have my fingers crossed, but I never hear anyone mention this part of it–only whether the transport can be built and paid for.

20. Cost.

21. > put the hardware we have in a 1 g rotating factory

    Then you’d still need all the structural support, heavy lift equipment (if applicable to the process), life support, thermal management, etc etc. It’s still far from straightforward.

22. “Takes a lot of R&D to migrate an Earth process to space.” Not to sound smart-a, but you *could* put the hardware we have in a 1 g rotating factory and go from there, with cheap energy and materials.

23. Cheapest to make the fuel near the point of use. Making fuel on Mars isn’t any more difficult than making it on the Moon.

24. Looks interesting, but even with 100% efficiency, you’d still need to process a lot of air if you want to extract CO2 from ambient atmosphere. So still not easy nor cheap. Just cheaper.

    The “carbon nanotube composite negative electrode” won’t help the cost either, though I think the nanotubes are only there for high-porosity support, so they can probably use cheaper porous materials. It also says they’ve demonstrated down to 6000 ppm CO2. They claim it should work with ambient air at 400 ppm, but looks like they haven’t tested it that low.

    It would be easier to capture CO2 from a concentrated stream such as the output of a power plant. But then it would be more energetically efficient to just sell the renewable electricity that you’d use to convert CO2 to methane to the grid, to offset some of the power plant capacity, and buy the fossil fuel methane that the power plant would have burnt. You’d get more methane for the same amount of electricity, and your plant and operational costs would be lower.

    But if you do have a good source of CO2, E-TAC water splitting from H2Pro can complete the picture for methane production. They claim over 98% energetic efficiency (still waiting for to cover them).
    https://www.h2pro.co/our-technology

25. My orig comment was using Starship as *x* in the O’Neill plan, where x will be easier in Space than on Earth, or any planet, in the basic Physics. Thus, O’Neill points out, we should get started already! I am not disagreeing as to the difficulty, but realize that that is why we need to get to work. So I was indeed asking about a general product factory, which would be easy after the Starship factory was built.
    There is great opportunity in 0g manufacturing other than the obvious ease of movement. Foams of almost anything, alloys of almost any metals we cannot even experiment with on Earth.
    Or we could do Mars Direct instead.

26. Now this is a good level of thinking. There are all sorts of ways to re-absorb the launch C, for instance, but they are not *solutions* to the problem, as they could re-absorb other C instead. Like paying for Mars with stock trading edge is not a way to make Mars profitable. That money could be used for Space Solar instead, for instance. We are at a point where the details are becoming important, as things are suddenly affordable, not just possible.
    For example, why not make the fuel on/near the Moon, for everybody, then ship some of it to Mars instead of the complexity of making that part on Mars?
    Assuming you want to go to Mars at all, let alone only.

27. Yes, easier now, and in the near-to-medium term, until all of that other industrial infrastructure is developed and deployed. By the time such infrastructure is deployed, they won’t be building Starships anymore, so it’s not relevant to a Starship factory.

    If you had asked about a more general spaceship factory in orbit, it would be more relevant. But then my answer would be quite different (more Starships). Or rather, I’d have trouble answering at all, since the scope of the task would be too large to estimate easily.

    P.S. edit:
    > After we can do something on Earth, we know how to do it in Space

    If only it was that easy. Space is hard. Hardware needs to be specially designed, processes adjusted, everything qualified, tested, etc. Takes a lot of R&D to migrate an Earth process to space.

28. Lunar carbon is still far less proven than Lunar water (LCROSS is just one local result). But I agree Lunar fuel can be included in the plan, at the cost of additional engineering complexity.

    But even then, the emissions from just 1000 launches (instead of 6000) would still qualify as a small(er) country. And those 1000 launches would still be needed to launch the colonists, unless SpaceX undertake more extreme measures.

29. However, see this. I hope it works as well as they are claiming.
    If it does it makes George Olah’s Methanol economy practical.
    https://www.greencarcongress.com/2019/10/20191027-mitcc.html

30. Easier *now*. This is different from *physics* easier. Launch is the problem, at all scales. and enables O’Neill more quickly as it gets cheaper. It is never the smart way, especially if you have bigger goals than Mars, which many do. Things like solving global heating with Space Solar. Do it only as needed to set up in Space. (edit: Think 3D printers and such). After we can do something on Earth, we know how to do it in Space, but don’t need the monster cranes, expensive energy, or Earth mining. Why is this not obvious? It seems incredibly counter intuitive, but otherwise clear.

31. Agree. The tech is certainly useful, but why would opening up fractional g planets be a goal except for science or *oddballs*? We will be living in O’Neill Space, where there is enuf room to make a difference, not tiny planets. And so much easier than living on Earth, let alone Mars.

32. Given this tech, and the fact that O’Neill is correct at large scales even more than at beginning scales, where we are due to the fact that we have wasted 40 years NOT doing lunar dev, we should have a billion in Space by the time a million are on Mars.

33. Assuming 5 refueling launches per trip assumes he is too stupid to use lunar C for fuel, or even H, like every other plan.

34. The problem with that on Earth is that atmospheric CO2 is very dilute here. They’d need to process huge volumes of air, which is neither easy nor cheap. It would be easier for them to buy a farm and make biomethane (probably a very large farm).

35. Musk did mention eventually they can make Starship carbon-neutral by using solar power to manufacture methane from water and atmospheric carbon dioxide. Electrical power from solar panels run water electrolysis to generate hydrogen, which is then used with carbon dioxide in the Sabatier reaction to generate methane and oxygen.

    This process by the way is central to SpaceX’s Mars plans– Only way to return to Earth from Mars using a Starship requires ISRU manufacturing of methane and LOX from Martian atmospheric CO2 and underground water ice deposits.

36. If they can make the starship part cheap enough they could just make it expendable and use the starship itself for material/storage/habitat on Mars. I don’t see the point in sending starships back to earth when you could use it on Mars and you can construct a new starship faster on earth than the travel time it would take to get from Mars back to Earth.

37. Those wouldn’t be Starships anymore (at least not the current version number), so the quote still has its math wrong.

    But I agree, the large fleets will more likely be with a future generation of ships.

38. Before they need 1000 Starships every 2 years, they will surely be thinking about the next generation of launchers that can take significant more mass to orbit, or even about dedicated space liners that remain in orbit.

    Probably the first option, given they don’t seem to trust over-complicated solutions.

39. I’d guess about a dozen or so, given reuse (edit: Was assuming just the bodywork and assembly plant. Raptors and other interior parts would need much more infrastructure. Easier to mass-produce them on Earth).

40. To put some numbers on it:

    ~4500 tons of methalox per launch, IIRC the most recent numbers. Assume 5 refuling launches per ship, so total 6 launches per ship.
    1000 ships * 6 * 4500 = 27 million tons of methalox.

    Of that, carbon if 15% by mass, so ~4 million tons, which translates to a little under 15 million tons of CO2.

    Total global CO2 emissions are ~2500 times higher. But this does qualify as a small country.

41. > Elon would want to fly fleets of 100 Starships every two years to Mars over a twenty-year period. This would put 1 million tons of cargo onto Mars.

    At ~100 tons per ship, 100 ships x 10 trips would only transfer 100,000 tons. To transfer 1 million tons, you’d need 1000 ships in each trip x 10 trips. I think that’s what Elon meant in his tweets.

42. How many Starships to set up a Starship manufacturing plant in ELEO, using lunar mass driver delivered to Moon by Starships?

43. when they list carbon emissions by countries… they are going to need to list spacex as a country because it’s carbon footprint from launching 1000 starship rockets is going to equal a small country…Lucky trump pulled out of climate treaty

44. I think Elon’s estimate for the cost of Starship/Superheavy has come down since 2017. The recent $100M seems to be for the full stack of Starship & Superheavy (Cargo/Tanker) current Stainless Steel version. They just need 1 Superheavy for several Starships.

45. Amazing to imagine this can be a reality in a decade or so, and I mean for public consumption.

    The first ones will be highly publicized events, with billionaires and government vying for a spot in the most media impactful space event ever, yeah, even more so than Apollo XI, which happened in a time before the Internet.

    It will be an interesting next decade, with many ups and downs and several first time ever events.

    It may happen that after the initial feverish rush, things settle down to a more normal “it exists and slowly grows” phase, though. Possibly after they realize we need Earth’s gravity more than we think right now. Making Lunar and Martian settlements and trips the domain of those looking for the adventure of a lifetime, but not for those looking for making a family and stay over there.

    In my belief, space settlement needs far more development to really happen, mostly in making it as safe and cheap as possible for mass consumption, with automation and development of rotating habitats. But the first ones to go to fractional G places will definitely open up other things for the rest of us, probably at some personal cost.

Comments are closed.