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I read a good analysis of Artemis a while back that essentially calculated the cost per hour of time-on-moon and in that sense it was easy to see that the progr

I read a good analysis of Artemis a while back that essentially calculated the cost per hour of time-on-moon and in that sense it was easy to see that the program was a significant upgrade over Apollo and the costs weren't that bad when calculated per hour. Achieving a 10x improvement over the previous generation usually can't be done without doing something new and different that hasn't been done before, and in-orbit refuelling fits right in. Gemini and Apollo had to work out and develop far more tech to do what they needed to do.

ChicagoBoy11 3y ago
What's also fascinating is that they are going with, in VERY BROAD strokes, the concept that was Von Braun's preferred method to achieve this back in the day too, but it was abandoned in favor of the lunar orbit rendesvouz. For a critique of the current method, I found the SmarterEveryDay lecture on it gave some good food for thought!
- jauntywundrkind 3y ago
  What were Von Braun's reasons for something akin to a Near Rectilinear Halo Orbit? Links anyone? The SmarterEverDay concerns about the orbit seemed to be that while landing or taking off maneuvers were short & low energy (good), it meant the opportunity only came about every couple days (bad). SED also stressed that Artemis is relying on crulyonic fuel transfer. SED repeatedly pointed out this is a tech that has never been tested, ever.
  - angiosperm 3y ago
    6 days (worse).
- nerpderp82 3y ago
  I watched the SmarterEveryDay lecture last night, so I was primed for this story. He mentioned fuel transfer being a huge unknown. https://www.youtube.com/watch?v=OoJsPvmFixU https://www.youtube.com/watch?v=OoJsPvmFixU The other thing he mentioned was the Apollo success playbook (SP-287), "What Made Apollo a Success?" https://ntrs.nasa.gov/api/citations/19720005243/downloads/19720005243.pdf https://ntrs.nasa.gov/api/citations/19720005243/downloads/19... Link to EPUB version https://old.reddit.com/r/SmarterEveryDay/comments/18aw4ca/i_converted_sp287_what_made_apollo_a_success_into/ https://old.reddit.com/r/SmarterEveryDay/comments/18aw4ca/i_...
- XorNot 3y ago
  The more I've thought about that lecture the less I really agree with most of the things he raised, for the simple reason that Apollo is never, ever going to happen again. It's a lot of argument from increduality (e.g. it's easy to pretend starship launch's are "too many", without addressing that practical reusability has been a thing for years right now). At it's peak, the Apollo project was funded to the tune of 1.1% total US federal outlays during the time period it ran. That's an enormous amount of money, which failed to produce a remotely sustainable result. You got what you got: moon landings done quick, and then never again. The modern Apollo project is SLS which...is a big, expensive, absolutely cannot fail rocket (which is really a jobs program for preferred contractor districts, with technology choices decided by politicians not engineers). Basically the SED lecture spends a lot of time gesturing at Apollo, but never addresses the actual problem which is NASA is funded the way it's funded: of course they know they're going to miss their launch dates, they're not funded to hit them, and they're probably going to wind up redesigning the mission once Starship is flying to orbit and actual performance numbers are realized off-paper. The SLS is the SLS for the same reason: at the time the program started there was no SpaceX, nor Space Shuttle and it was something of a national embarrassment the US didn't have a manned space capability but the Russians still did. In short, for a lecture which opens talking about people worrying about disagreeing with their superiors, he stays well away from the actual live-wires of the issues.
justrealist 3y ago
Yeah Apollo was obviously incredibly impressive but was sort of a technological dead-end. There was no path from that program to a permanent human presence on the moon. If they can really get Starship and orbital refueling working, it's a step function forward.
- panick21_ 3y ago
  I tend to disagree. There was very much a evolutionary path forward. There were already programs like NERVA in development for an advanced nuclear upper stage. Once you have that, making the Upper Stage refuel-able, makes it basically into a multi-use space tug for cis-lunar. Then you could evolve Saturn 1B into a reusable Saturn 1C, just like Falcon 9. That gives you a reusable heavy lifter. And it would also safe a gigantic amount of money that was spend on Atlas/Titan/Delta in the next 40 years. The Apollo capsule was not reusable but continuously evolving a capsule design in that direct was certainty possible. But its not the most important part of the system in terms of cost. What really need more development is the lander itself. Making a large reusable lander would have been costly but not really out of reach. You can use an occasional Saturn V for large things like Skylab and special deep space mission. That was a much better path forward then Space Shuttle and ISS.
- cratermoon 3y ago
  > a technological dead-end. "The Apollo lunar base proposal saw an uncrewed Saturn V used to land a shelter based on the Apollo Command/Service Module (CSM) on the Moon." <https://en.wikipedia.org/wiki/Apollo_Applications_Program#AES_(Apollo_Extension_Series)_Lunar_Base https://en.wikipedia.org/wiki/Apollo_Applications_Program#AE...>
  - justrealist 3y ago
    I feel this somewhat glosses over the unsolved challenge of how to land a Saturn V rocket.
    - jdminhbg 3y ago
      Much easier to do on the moon than on Earth though at least, right? No atmosphere, fraction of the gravity.
panick21_ 3y ago
Its hard to calculate because non of the costs are really all that clear. There are not even lander contracts for any mission after Artemis 3. It also depends on how long into to future you think this continue. And I think what that kind of analysis misses is how many important multi-use technologies are developed. Starship will mostly not be used for moon, but financed with moon money.
YetAnotherNick 3y ago
> Achieving a 10x improvement over the previous generation usually can't be done without doing something new It is definitely possible if the fixed cost(e.g. R and D, manufacturing capability, testing infrastructure etc) is majority of the cost and scaling up doesn't increase them linearly. Cost of raw materials like fuel or building material would be negligible for Apollo or SLS in comparison.
danbruc 3y ago
How does this work out? Instead of one rocket they will have to launch a dozen or so rockets for one visit to the moon. Why did they choose this option to begin with? And is cost per time on moon not a bit misleading, just stay longer and this cost goes down? You obviously have to bring more food and air and so on, but is that really a significant amount? Or are there other limiting factors that prevent you from staying say a month?
- idontwantthis 3y ago
  > Why did they choose this option to begin with Because this will be the first time in history that the cost of a launch will be mostly the cost of the fuel. This is the first fully reusable rocket in history. If you had to throw away a dozen tankers it wouldn’t make any sense.
  - alemanek 3y ago
    Also being able to bring 100 tonnes to the surface of the moon is a fantastic reason as well. Everyone can bring a set of golf clubs and balls. Heck we can setup a little driving range with the extra mass allowance.
    - angiosperm 3y ago
      Notably, we don't need to bring 100 tonnes to the surface of the moon. Or golf clubs. Stable hypergolic fuel would be useful, but there are no plans for that.
      - alemanek 3y ago
        NASA has stated they want to maintain a long term presence on the moon. If we take them at their word then we absolutely do need to be able to bring 100 tons to the surface of the moon. Water, food, air, parts, habitats, ..etc. All of that adds up. Super Heavy lift capability and refueling will be vital to making those plans feasible.
  - danbruc 3y ago
imtringued 3y ago
The problem with EVA on the moon is the reliability and endurance of the space suits. Even if HLS delivers, there could be delays simply because there are no suits. When you consider the near rectilinear orbit having a seven day period, then bad suits are a deal breaker for the entire mission.
- XorNot 3y ago
  Conversely if you have reliable payload to the lunar surface, delivering special-use lunar escape vehicles to keep on standby is a better option then having the entire mission pay an ongoing cost for what should be an exceptional and unlikely scenario. The problem of "we need to get off the moon now" is "okay, but where are you going and what's going to be there that's more useful then where you are?" It's not unreasonable to note that a medical emergency would be much better dealt with on the moon - where you have gravity - then in orbit, where you don't. Whereas if you need to bail out and get to Earth fast (which you can't) then you'd be better off just dropping a vehicle which can do that onto the surface.

ChicagoBoy11 3y ago

What's also fascinating is that they are going with, in VERY BROAD strokes, the concept that was Von Braun's preferred method to achieve this back in the day too, but it was abandoned in favor of the lunar orbit rendesvouz. For a critique of the current method, I found the SmarterEveryDay lecture on it gave some good food for thought!

jauntywundrkind 3y ago
What were Von Braun's reasons for something akin to a Near Rectilinear Halo Orbit? Links anyone? The SmarterEverDay concerns about the orbit seemed to be that while landing or taking off maneuvers were short & low energy (good), it meant the opportunity only came about every couple days (bad). SED also stressed that Artemis is relying on crulyonic fuel transfer. SED repeatedly pointed out this is a tech that has never been tested, ever.
- angiosperm 3y ago
  6 days (worse).
nerpderp82 3y ago
I watched the SmarterEveryDay lecture last night, so I was primed for this story. He mentioned fuel transfer being a huge unknown. https://www.youtube.com/watch?v=OoJsPvmFixU https://www.youtube.com/watch?v=OoJsPvmFixU The other thing he mentioned was the Apollo success playbook (SP-287), "What Made Apollo a Success?" https://ntrs.nasa.gov/api/citations/19720005243/downloads/19720005243.pdf https://ntrs.nasa.gov/api/citations/19720005243/downloads/19... Link to EPUB version https://old.reddit.com/r/SmarterEveryDay/comments/18aw4ca/i_converted_sp287_what_made_apollo_a_success_into/ https://old.reddit.com/r/SmarterEveryDay/comments/18aw4ca/i_...
XorNot 3y ago
The more I've thought about that lecture the less I really agree with most of the things he raised, for the simple reason that Apollo is never, ever going to happen again. It's a lot of argument from increduality (e.g. it's easy to pretend starship launch's are "too many", without addressing that practical reusability has been a thing for years right now). At it's peak, the Apollo project was funded to the tune of 1.1% total US federal outlays during the time period it ran. That's an enormous amount of money, which failed to produce a remotely sustainable result. You got what you got: moon landings done quick, and then never again. The modern Apollo project is SLS which...is a big, expensive, absolutely cannot fail rocket (which is really a jobs program for preferred contractor districts, with technology choices decided by politicians not engineers). Basically the SED lecture spends a lot of time gesturing at Apollo, but never addresses the actual problem which is NASA is funded the way it's funded: of course they know they're going to miss their launch dates, they're not funded to hit them, and they're probably going to wind up redesigning the mission once Starship is flying to orbit and actual performance numbers are realized off-paper. The SLS is the SLS for the same reason: at the time the program started there was no SpaceX, nor Space Shuttle and it was something of a national embarrassment the US didn't have a manned space capability but the Russians still did. In short, for a lecture which opens talking about people worrying about disagreeing with their superiors, he stays well away from the actual live-wires of the issues.

justrealist 3y ago

Yeah Apollo was obviously incredibly impressive but was sort of a technological dead-end. There was no path from that program to a permanent human presence on the moon. If they can really get Starship and orbital refueling working, it's a step function forward.

panick21_ 3y ago
I tend to disagree. There was very much a evolutionary path forward. There were already programs like NERVA in development for an advanced nuclear upper stage. Once you have that, making the Upper Stage refuel-able, makes it basically into a multi-use space tug for cis-lunar. Then you could evolve Saturn 1B into a reusable Saturn 1C, just like Falcon 9. That gives you a reusable heavy lifter. And it would also safe a gigantic amount of money that was spend on Atlas/Titan/Delta in the next 40 years. The Apollo capsule was not reusable but continuously evolving a capsule design in that direct was certainty possible. But its not the most important part of the system in terms of cost. What really need more development is the lander itself. Making a large reusable lander would have been costly but not really out of reach. You can use an occasional Saturn V for large things like Skylab and special deep space mission. That was a much better path forward then Space Shuttle and ISS.
cratermoon 3y ago
> a technological dead-end. "The Apollo lunar base proposal saw an uncrewed Saturn V used to land a shelter based on the Apollo Command/Service Module (CSM) on the Moon." <https://en.wikipedia.org/wiki/Apollo_Applications_Program#AES_(Apollo_Extension_Series)_Lunar_Base https://en.wikipedia.org/wiki/Apollo_Applications_Program#AE...>
- justrealist 3y ago
  I feel this somewhat glosses over the unsolved challenge of how to land a Saturn V rocket.
  - jdminhbg 3y ago
    Much easier to do on the moon than on Earth though at least, right? No atmosphere, fraction of the gravity.

panick21_ 3y ago

Its hard to calculate because non of the costs are really all that clear. There are not even lander contracts for any mission after Artemis 3. It also depends on how long into to future you think this continue. And I think what that kind of analysis misses is how many important multi-use technologies are developed. Starship will mostly not be used for moon, but financed with moon money.

YetAnotherNick 3y ago

> Achieving a 10x improvement over the previous generation usually can't be done without doing something new It is definitely possible if the fixed cost(e.g. R and D, manufacturing capability, testing infrastructure etc) is majority of the cost and scaling up doesn't increase them linearly. Cost of raw materials like fuel or building material would be negligible for Apollo or SLS in comparison.

danbruc 3y ago

How does this work out? Instead of one rocket they will have to launch a dozen or so rockets for one visit to the moon. Why did they choose this option to begin with? And is cost per time on moon not a bit misleading, just stay longer and this cost goes down? You obviously have to bring more food and air and so on, but is that really a significant amount? Or are there other limiting factors that prevent you from staying say a month?

idontwantthis 3y ago
> Why did they choose this option to begin with Because this will be the first time in history that the cost of a launch will be mostly the cost of the fuel. This is the first fully reusable rocket in history. If you had to throw away a dozen tankers it wouldn’t make any sense.
- alemanek 3y ago
  Also being able to bring 100 tonnes to the surface of the moon is a fantastic reason as well. Everyone can bring a set of golf clubs and balls. Heck we can setup a little driving range with the extra mass allowance.
  - angiosperm 3y ago
    Notably, we don't need to bring 100 tonnes to the surface of the moon. Or golf clubs. Stable hypergolic fuel would be useful, but there are no plans for that.
    - alemanek 3y ago
      NASA has stated they want to maintain a long term presence on the moon. If we take them at their word then we absolutely do need to be able to bring 100 tons to the surface of the moon. Water, food, air, parts, habitats, ..etc. All of that adds up. Super Heavy lift capability and refueling will be vital to making those plans feasible.
- danbruc 3y ago

imtringued 3y ago

The problem with EVA on the moon is the reliability and endurance of the space suits. Even if HLS delivers, there could be delays simply because there are no suits. When you consider the near rectilinear orbit having a seven day period, then bad suits are a deal breaker for the entire mission.

XorNot 3y ago
Conversely if you have reliable payload to the lunar surface, delivering special-use lunar escape vehicles to keep on standby is a better option then having the entire mission pay an ongoing cost for what should be an exceptional and unlikely scenario. The problem of "we need to get off the moon now" is "okay, but where are you going and what's going to be there that's more useful then where you are?" It's not unreasonable to note that a medical emergency would be much better dealt with on the moon - where you have gravity - then in orbit, where you don't. Whereas if you need to bail out and get to Earth fast (which you can't) then you'd be better off just dropping a vehicle which can do that onto the surface.