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Blue Origin said it would be 16, Musk has claimed it won't be more than 8. https://wccftech.com/musk-rejects-blue-origins-claim-of-16-spacex-launches-for-moon-

Blue Origin said it would be 16, Musk has claimed it won't be more than 8. https://wccftech.com/musk-rejects-blue-origins-claim-of-16-spacex-launches-for-moon-lander/ https://wccftech.com/musk-rejects-blue-origins-claim-of-16-s... It ends up being ~100,000 launches over 10 launch windows. Elon has talked about building 1000 starships (presumably you would need less boosters) https://www.tesmanian.com/blogs/tesmanian-blog/1000-starships https://www.tesmanian.com/blogs/tesmanian-blog/1000-starship... Anyway, it's absolutely the case that transferring a million tons of cargo will require a new way of thinking about the scale of launches.I would also not assume that the refueling launches have to all take place within the window, that's a bad assumption to start with. You would start your refueling launches well ahead of the window. added point - I do think the article overlooks that while Starship will change things, the timing is likely to be slow enough that NASA will be able to adapt. They do have ridiculous timelines on some of their projects, but just like everything else, they will just rewrite those timelines if new solutions present themselves.

qayxc 5y ago
Even 90,000 launches over 10 launch windows is 9,000 launches per window. Launch opportunities are about 30 days max per window (depending on the flight profile) so that'd be 300 launches per day or over 12 launches per hour . I'm not saying this is bonkers, but this is completely ridiculous and it doesn't matter whether it's 90,000 or 180,000 or even "just" 45,000 launches - it's completely impractical. Not to mention that proponents always act as if it's no biggie to just crank out thousands of metric tons of useful equipment for a permanent Mars settlement in just a couple of years. You, know, including R&D and engineering and paying for all that.
- altcognito 5y ago
  Don't assume that launches for refueling operations happen during the launch window. The window is really as long as you want it to be for refueling. Yes, there are engineering challenges associated with having fuel in orbit over a longer period. I'll agree there is a shortage of plans and an excess of hope in what you're going to ship to Mars in the near term. But I can also see where others are saying -- something this big requires a slow organization like NASA to start planning now.
  - SECProto 5y ago
    > Don't assume that launches for refueling operations happen during the launch window. The window is really as long as you want it to be for refueling. Indeed, the parent comment was making a bad assumption. If you look at it that way, refueling can happen anytime in the 2-years between windows. So say 10,000 launches over 730 days is 13 or 14 launches per day. Given multiple launch sites, seems feasible enough (in the same sense of feasible as producing 100,000 tonnes of goods destined for mars every 2 years).
    - skedaddle 5y ago
      Launching isn't the whole mission though, even if you can achieve that rate. For every launch you also need hours of time for rendezvous, docking, and fuel transfer. And even if somehow there is a solution to this schedule, you're talking about doing it 10,000 times safely and without a hitch.
- gremloni 5y ago
  Based on what, your gut feel? 12 launches per hour does not seem insane at all.
  - ClumsyPilot 5y ago
    Based on the fact that it would be more flying mass than the domestic airline industry.
  - vanattab 5y ago
    In 2020 there was 114 orbital launches supporting all space missions around the world. That's 0.013 launches per hour. 12 launches per hour to support a single mission does not seem at least a little insane? I love SpaceX and am hopeful for their Mars plans but we are scientists and engineers let's think with our brains and not our hearts.
    - gremloni 5y ago
      Think about what you’re saying, does 12 launches per hour sound all that crazy? Maybe having 1000s of planes up in the air at the same time would have sounded similarly crazy to someone on the 50s
    - brianwawok 5y ago
      if computers taught me anything.. it's if you can do 1 thing really really well perfectly, it's not a ton of work to do it 10x or 100x in parallel. We don't have enough data to know reliability of say Falcon long term. Is it 99% successful? 99.9%? 99.999999%? Doing a ton of launches, you really want to work on the 9s, so 0-1 of your launches blow up, not 100+. But once you do, you just copy paste it baby and go to town.
      - vanattab 5y ago
        I am not convinced the scalability of cyberspace applies to actual space.
        5y ago
- atq2119 5y ago
  Genuine question: how important is the launch window when you start thinking about bulk transport to Mars? If you build thousands of starships, how much does it matter if some of them are slower to arrive? It's not like flying to Mars is impossible outside the launch window. It takes longer and probably needs more fuel, but by how much?
  - qayxc 5y ago
    > how important is the launch window when you start thinking about bulk transport to Mars? Launch windows aren't just about time of travel. They are primarily about the energy required to get to your target. You can in principle launch to anywhere at any given moment, but the required energy will be much higher. So high in fact, that a Starship-type spacecraft would be unable to make the trip due to lack of fuel. Hyperbolic trajectories require higher energies and the exact amount involves solving partial differential equations that depend on the exact orbital configuration (i.e. date and location of launch), so I cannot provide a general answer as to how much more fuel would be required. Suffices to say it would take more fuel than a Starship is able to carry and a hyperbolic trajectory would require en-route refuelling, which is basically impossible since the tankers/fuel depot would have to move at the same speed.
abledon 5y ago
> It ends up being ~100,000 launches over 10 launch windows. Elon has talked about building 1000 starships managing that many launches...spaceships mid-journey, refueling in space ETC... would the 'head count' at spaceX have to increase greatly, or would they keep a relatively small crew and just 'scale out' having it mostly controlled by code/automation
- brianwawok 5y ago
  For sure both.

qayxc 5y ago

Even 90,000 launches over 10 launch windows is 9,000 launches per window. Launch opportunities are about 30 days max per window (depending on the flight profile) so that'd be 300 launches per day or over 12 launches per hour . I'm not saying this is bonkers, but this is completely ridiculous and it doesn't matter whether it's 90,000 or 180,000 or even "just" 45,000 launches - it's completely impractical. Not to mention that proponents always act as if it's no biggie to just crank out thousands of metric tons of useful equipment for a permanent Mars settlement in just a couple of years. You, know, including R&D and engineering and paying for all that.

altcognito 5y ago
Don't assume that launches for refueling operations happen during the launch window. The window is really as long as you want it to be for refueling. Yes, there are engineering challenges associated with having fuel in orbit over a longer period. I'll agree there is a shortage of plans and an excess of hope in what you're going to ship to Mars in the near term. But I can also see where others are saying -- something this big requires a slow organization like NASA to start planning now.
- SECProto 5y ago
  > Don't assume that launches for refueling operations happen during the launch window. The window is really as long as you want it to be for refueling. Indeed, the parent comment was making a bad assumption. If you look at it that way, refueling can happen anytime in the 2-years between windows. So say 10,000 launches over 730 days is 13 or 14 launches per day. Given multiple launch sites, seems feasible enough (in the same sense of feasible as producing 100,000 tonnes of goods destined for mars every 2 years).
  - skedaddle 5y ago
    Launching isn't the whole mission though, even if you can achieve that rate. For every launch you also need hours of time for rendezvous, docking, and fuel transfer. And even if somehow there is a solution to this schedule, you're talking about doing it 10,000 times safely and without a hitch.
gremloni 5y ago
Based on what, your gut feel? 12 launches per hour does not seem insane at all.
- ClumsyPilot 5y ago
  Based on the fact that it would be more flying mass than the domestic airline industry.
- vanattab 5y ago
  In 2020 there was 114 orbital launches supporting all space missions around the world. That's 0.013 launches per hour. 12 launches per hour to support a single mission does not seem at least a little insane? I love SpaceX and am hopeful for their Mars plans but we are scientists and engineers let's think with our brains and not our hearts.
  - gremloni 5y ago
    Think about what you’re saying, does 12 launches per hour sound all that crazy? Maybe having 1000s of planes up in the air at the same time would have sounded similarly crazy to someone on the 50s
  - brianwawok 5y ago
    if computers taught me anything.. it's if you can do 1 thing really really well perfectly, it's not a ton of work to do it 10x or 100x in parallel. We don't have enough data to know reliability of say Falcon long term. Is it 99% successful? 99.9%? 99.999999%? Doing a ton of launches, you really want to work on the 9s, so 0-1 of your launches blow up, not 100+. But once you do, you just copy paste it baby and go to town.
    - vanattab 5y ago
      I am not convinced the scalability of cyberspace applies to actual space.
      - 5y ago
atq2119 5y ago
Genuine question: how important is the launch window when you start thinking about bulk transport to Mars? If you build thousands of starships, how much does it matter if some of them are slower to arrive? It's not like flying to Mars is impossible outside the launch window. It takes longer and probably needs more fuel, but by how much?
- qayxc 5y ago
  > how important is the launch window when you start thinking about bulk transport to Mars? Launch windows aren't just about time of travel. They are primarily about the energy required to get to your target. You can in principle launch to anywhere at any given moment, but the required energy will be much higher. So high in fact, that a Starship-type spacecraft would be unable to make the trip due to lack of fuel. Hyperbolic trajectories require higher energies and the exact amount involves solving partial differential equations that depend on the exact orbital configuration (i.e. date and location of launch), so I cannot provide a general answer as to how much more fuel would be required. Suffices to say it would take more fuel than a Starship is able to carry and a hyperbolic trajectory would require en-route refuelling, which is basically impossible since the tankers/fuel depot would have to move at the same speed.

abledon 5y ago

> It ends up being ~100,000 launches over 10 launch windows. Elon has talked about building 1000 starships managing that many launches...spaceships mid-journey, refueling in space ETC... would the 'head count' at spaceX have to increase greatly, or would they keep a relatively small crew and just 'scale out' having it mostly controlled by code/automation

brianwawok 5y ago
For sure both.