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I think that understanding of the consensus is incorrect. The mission plan for Artemis 3 is that a specialized Starship upper stage will be refueled in LEO and

I think that understanding of the consensus is incorrect. The mission plan for Artemis 3 is that a specialized Starship upper stage will be refueled in LEO and then transfer to lunar orbit where it will wait for astronauts arriving on SLS/Orion. Yes the mission profile is more complex, but that complexity can mostly be settled before the astronauts launch on their mission. NASA seems to think it is a viable plan which is why they selected SpaceX to execute that part of the mission.

fluoridation 1y ago
Wikipedia: > After a multi-phase design effort, on April 16, 2021, NASA selected SpaceX to develop Starship HLS and deliver it to near-rectilinear halo orbit (NRHO) prior to arrival of the crew for use on the Artemis III mission. The delivery requires that Starship HLS be refueled in Earth orbit before boosting to the NRHO, and this refueling requires a pre-positioned propellant depot in Earth orbit that is filled by multiple (at least 14) tanker flights. I stand by what I said: not happening. I'll believe it when I see it. Can you imagine if to make a sightseeing trip to another city you had to stop in the middle of the highway and then make 14 round-trips with a second car to fill your first car back up? I can't imagine why someone would approve this plan, other than corruption.
- DarmokJalad1701 1y ago
  > Can you imagine if to make a sightseeing trip to another city you had to stop in the middle of the highway and then make 14 round-trips with a second car to fill your first car back up? If the alternative was throwing away and building/buying a new car for every trip? Absolutely. They said the same about landing a first stage booster - impossible and pointless to attempt. And it just happened for the 400th time yesterday.
  - fluoridation 1y ago
    And yet the boosters are not being reused. They're just making brand new engines for every launch. If we're generous they're being dismantled and recycled.
    - stetrain 1y ago
      They were talking about Falcon 9, which is absolutely being reused.
      - fluoridation 1y ago
        Alright, if we're talking about Falcon 9, I don't know what the cost savings are for a reusable rocket, or if there are any. If someone has that data, feel free to provide it.
        0xffff2 1y ago
        There are a lot of variables, but very roughly, the Falcon 9 has cut launch costs in half compared to its competitors.
        Powdering7082 1y ago
        > As of 2024, SpaceX's internal costs for a Falcon 9 launch are estimated between $15 million[186] and $28 million,[185] factoring in workforce expenses, refurbishment, assembly, operations, and facility depreciation.[187] These efficiencies are primarily due to the reuse of first-stage boosters and payload fairings.[188] The second stage, which is not reused, is believed to be the largest expense per launch, with the company's COO stating that each costs $12 million to produce.[189] From wikipedia: https://en.wikipedia.org/wiki/Falcon_9#Pricing https://en.wikipedia.org/wiki/Falcon_9#Pricing
  - dmbche 1y ago
    False dichotomy - the mission profile dictates the refuelling station and all that, but it never was the only option. Somehow we've decided we needed to be able to do lots of trips to the moon for Artemis, but it's not clear to me that it's such a precious golden oportunity and warrants this spending/impact on the environnenent. We didn't get to the moon with a refuelling station did we? How come we need one now? We're really seeing 15 starship launches per moon trip as reasonable, rather than just building a single trip program? The mission itself is nonsensical. The problems are stemming from the SLS, I'll find a link to a relevant source.
    - stetrain 1y ago
      The Apollo missions landed two crew members in a tin can with extreme limits on what weight they could bring with them in either direction. A single trip launch will always be constrained like this due to the tyranny of the rocket equation. A modular mission system with multiple launches is the best way to expand capabilities and enable things like landing larger payloads for more advanced or long-term missions.
      - fluoridation 1y ago
        There's never going to be long-term crewed missions to the Moon. It has no scientific value. Even the little exploration we did in the '60s and '70s were a dubious proposition. There's not that much we could do by sending people that we couldn't do by sending robots.
        stetrain 1y ago
        If you think there's no value to returning to the moon, building a base, etc. then fine. But you keep moving the goalposts of what you are taking issue with here.
        fluoridation 1y ago
        I didn't move any goalposts. 1. Starship is never going to be usable for a Moon mission. 2. There's little scientific value in Moon missions. 3. There's never going to be long-term missions to the Moon. I maintain all three simultaneously.
- stetrain 1y ago
  How did the fuel you put in your car get there? Your car didn't come with all of the fuel for the trip, nor did it spawn at the gas pump. It was pumped, shipped, refined, and trucked to that point using a complex supply chain, enabling your final trip to happen with one fuel transfer.
- redox99 1y ago
  You can easily mathematically prove that orbital refueling increases mission efficiency. This is a simple fact, it's not about Starship or whatever. Your analogy does not hold.
- stetrain 1y ago
  > I stand by what I said: not happening. I'll believe it when I see it. And it's totally valid for you to have that opinion. But it's your opinion, not "the consensus."
- slipperydippery 1y ago
  The mission is wildly more complicated than the Apollo missions. There's a whole oddball-orbit space station that has to be placed as a way-station, for one thing, and none of that's happened yet (remember how long it took to build the ISS?). Also, landing all your return fuel instead of leaving it in orbit, so a way heavier lander (with a smaller return payload than Apollo!), which is a pain in the ass. Multiple space ships launched by different rocket systems involved. The SLS still has to be finished for it to go forward. Orbital refueling of large fuel tanks is a hard problem that remains unsolved, and this goes nowhere without fixing that. The contracts for the return vehicles are disturbingly light on parts about making sure they can reliably work, including surviving re-entry. I'm with you. Not happening. We're more likely to come up with a totally different, simpler plan, and do that instead, before this happens.
  - stetrain 1y ago
    > landing all of your return fuel The fuel that is landed is used to get back from the lunar surface to lunar orbit, not to return to Earth. That fuel stays with Orion in NRHO.

fluoridation 1y ago

Wikipedia: > After a multi-phase design effort, on April 16, 2021, NASA selected SpaceX to develop Starship HLS and deliver it to near-rectilinear halo orbit (NRHO) prior to arrival of the crew for use on the Artemis III mission. The delivery requires that Starship HLS be refueled in Earth orbit before boosting to the NRHO, and this refueling requires a pre-positioned propellant depot in Earth orbit that is filled by multiple (at least 14) tanker flights. I stand by what I said: not happening. I'll believe it when I see it. Can you imagine if to make a sightseeing trip to another city you had to stop in the middle of the highway and then make 14 round-trips with a second car to fill your first car back up? I can't imagine why someone would approve this plan, other than corruption.

DarmokJalad1701 1y ago
> Can you imagine if to make a sightseeing trip to another city you had to stop in the middle of the highway and then make 14 round-trips with a second car to fill your first car back up? If the alternative was throwing away and building/buying a new car for every trip? Absolutely. They said the same about landing a first stage booster - impossible and pointless to attempt. And it just happened for the 400th time yesterday.
- fluoridation 1y ago
  And yet the boosters are not being reused. They're just making brand new engines for every launch. If we're generous they're being dismantled and recycled.
  - stetrain 1y ago
    They were talking about Falcon 9, which is absolutely being reused.
    - fluoridation 1y ago
      Alright, if we're talking about Falcon 9, I don't know what the cost savings are for a reusable rocket, or if there are any. If someone has that data, feel free to provide it.
      - 0xffff2 1y ago
        There are a lot of variables, but very roughly, the Falcon 9 has cut launch costs in half compared to its competitors.
      - Powdering7082 1y ago
        > As of 2024, SpaceX's internal costs for a Falcon 9 launch are estimated between $15 million[186] and $28 million,[185] factoring in workforce expenses, refurbishment, assembly, operations, and facility depreciation.[187] These efficiencies are primarily due to the reuse of first-stage boosters and payload fairings.[188] The second stage, which is not reused, is believed to be the largest expense per launch, with the company's COO stating that each costs $12 million to produce.[189] From wikipedia: https://en.wikipedia.org/wiki/Falcon_9#Pricing https://en.wikipedia.org/wiki/Falcon_9#Pricing
- dmbche 1y ago
  False dichotomy - the mission profile dictates the refuelling station and all that, but it never was the only option. Somehow we've decided we needed to be able to do lots of trips to the moon for Artemis, but it's not clear to me that it's such a precious golden oportunity and warrants this spending/impact on the environnenent. We didn't get to the moon with a refuelling station did we? How come we need one now? We're really seeing 15 starship launches per moon trip as reasonable, rather than just building a single trip program? The mission itself is nonsensical. The problems are stemming from the SLS, I'll find a link to a relevant source.
  - stetrain 1y ago
    The Apollo missions landed two crew members in a tin can with extreme limits on what weight they could bring with them in either direction. A single trip launch will always be constrained like this due to the tyranny of the rocket equation. A modular mission system with multiple launches is the best way to expand capabilities and enable things like landing larger payloads for more advanced or long-term missions.
    - fluoridation 1y ago
      There's never going to be long-term crewed missions to the Moon. It has no scientific value. Even the little exploration we did in the '60s and '70s were a dubious proposition. There's not that much we could do by sending people that we couldn't do by sending robots.
      - stetrain 1y ago
        If you think there's no value to returning to the moon, building a base, etc. then fine. But you keep moving the goalposts of what you are taking issue with here.
        fluoridation 1y ago
        I didn't move any goalposts. 1. Starship is never going to be usable for a Moon mission. 2. There's little scientific value in Moon missions. 3. There's never going to be long-term missions to the Moon. I maintain all three simultaneously.
stetrain 1y ago
How did the fuel you put in your car get there? Your car didn't come with all of the fuel for the trip, nor did it spawn at the gas pump. It was pumped, shipped, refined, and trucked to that point using a complex supply chain, enabling your final trip to happen with one fuel transfer.
redox99 1y ago
You can easily mathematically prove that orbital refueling increases mission efficiency. This is a simple fact, it's not about Starship or whatever. Your analogy does not hold.
stetrain 1y ago
> I stand by what I said: not happening. I'll believe it when I see it. And it's totally valid for you to have that opinion. But it's your opinion, not "the consensus."
slipperydippery 1y ago
The mission is wildly more complicated than the Apollo missions. There's a whole oddball-orbit space station that has to be placed as a way-station, for one thing, and none of that's happened yet (remember how long it took to build the ISS?). Also, landing all your return fuel instead of leaving it in orbit, so a way heavier lander (with a smaller return payload than Apollo!), which is a pain in the ass. Multiple space ships launched by different rocket systems involved. The SLS still has to be finished for it to go forward. Orbital refueling of large fuel tanks is a hard problem that remains unsolved, and this goes nowhere without fixing that. The contracts for the return vehicles are disturbingly light on parts about making sure they can reliably work, including surviving re-entry. I'm with you. Not happening. We're more likely to come up with a totally different, simpler plan, and do that instead, before this happens.
- stetrain 1y ago
  > landing all of your return fuel The fuel that is landed is used to get back from the lunar surface to lunar orbit, not to return to Earth. That fuel stays with Orion in NRHO.