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Idk how you took away that he was criticizing the Starship program at all. SpaceX pivots designs on a swivel, conducts tons of incremental tests, and ends up succeeding at the claimed impossible time and time again. If anything, NASA should be taking a cue from them.

He’s being directly critical of Artemis and Orion/SLS, which is not at all built that way, was basically architected by politics, and will probably not end up actually going to the moon unless there’s a major change.

In-orbit refueling, etc. Those are Starships not SLS being counted: 29:45

Talking about methane, in situ refueling (not just spacex, but they've been the most vocal): 41:25

Complexity/redundancy: 46:28 (looong pause and laughter)

Comments on engine design: ~48:00 (you have to be aware of Raptor/SS booster design to get the criticism)

Raptors right now look very nightmarish if used for landing crew on anything - the Earth or the Moon alike. The most advanced liquid fuel engine with tons of feedback loops looks suspiciously like a catastrophe waiting to happen at a worst possible moment.

Landing on the Moon is supposed to use some other engines as well at the time, so that may help. As soon as we'll know more about design, we can say things more confidently.

The Starship program is the big unknown in the whole mission. The SLS is boring and expensive and underperforming but it somewhat works. They should have given it more power to avoid the NRO, which appears to be a source of complexity due to the underperformance of the SLS. It makes things harder than it needs to be, but it isn't a death knell.

He clearly argued against flashy technology demonstrations like orbital refueling, which if you have paid attention, doesn't apply to the SLS but Starship. Orbital refueling adds an insane amount of uncertainty to the entire mission due to the boiling off of cryogenic fuels. He clearly pointed out that despite the plan of sending six Starships to LEO, nobody actually knows how many rocket flights are necessary. Fancy technology has been put on a pedestal, while the actual mission is being neglected. This is a common theme I have seen on HN and Reddit. SpaceX enthusiasts think the moon mission is some irrelevant symbolic political boondoggle to keep NASA facilities open. They all want to go on the promised 100 people trip to mars.

>will probably not end up actually going to the moon unless there’s a major change.

I don't know if you have paid attention lately, but currently Starship is significantly behind schedule. I'm not sure what to call this interpretation except "biased". Maybe this will refresh your memory: The Starship "Propellant Transfer Test" was supposed to happen in 2022 Q4.

EDIT: https://www.reddit.com/r/SpaceXLounge/comments/qujnsi/propos...

> He clearly argued against flashy technology demonstrations like orbital refueling, which if you have paid attention, doesn't apply to the SLS but Starship.

I think this ignores that a lander of significant size would need newly designed hypergolic engines and would need very complex orbital refueling of hypergolics as well.

> Fancy technology has been put on a pedestal, while the actual mission is being neglected.

I think this is just a misunderstanding of the long term vision for the program. I its not about Artemis 3 only.

> SpaceX enthusiasts think the moon mission is some irrelevant symbolic political boondoggle to keep NASA facilities open. They all want to go on the promised 100 people trip to mars.

That's unfair. SpaceX enthusiast for the most part are simply happy money flows into the Starship program. The real win here is the Starship program itself, not any individual mission.

And I think that is the most impactful thing about this, having impact all future deep space missions. So call me a SpaceX enthusiasts.

So unless you go to a tiny lander, its just a reality. Its in the critical path.

He's specifically criticizing the orbital refueling timeline and the use of methane+LOX instead of hypergolic propellant for the lander. The timeline will probably get pushed back and the lander development seems to still be in a very early stage and it may well be worth it to consider hypergolic fuel. Also the systems of the starship lander must be accessible for repair.

"but we have never attempted a cryogenic refuel in orbit (this seems like a biggie)"

Isn't this a consequence of having Sen. Richard Shelby in de facto control of cosmic spending for decades?

AFAIK Shelby was notorious for vetoing any project that included refueling in orbit. Fortunately, he finally retired at the ripe old age of 89.

(If longevity research pays off, we may never get rid of such entrenched people... or in 100 years or so.)

> We went to the moon 50+ years ago, but we are reinventing the wheel in some significant ways in Artemis. Why?

Because if we do it the same way we did 50+ years ago, we learn absolutely nothing and the whole thing is a pointless waste of money.

In order to progress and learn and improve you must do things you've never done before. You must be ambitious and you must attempt things that are difficult and will probably take many attempts to master.

This logic is exactly the same as saying "we've been burning toxic liquids for generations to get around. Why are we making things complicated with all these batteries and electric motors".

The whole point is improvement.

This strikes me as a moment where you should watch the video there's a moment specifically at 41:40 where he basically says what you're saying and it's an integral part of his point

I find that a lot of people myself included like to argue against an imagined version of something they hear second hand often not going to the source material to realize they're standing on the same side

A counterpoint to his thesis that the orbit and design have to be simple to succeed is the Mars rover sky crane lander system. It was terribly complex and, famously, worked very well. Compute has made a big difference since the 60s. Roughly every line of code today used to be a handful of physical components, whether it was an analog circuit or additional core memory wire-wound in the flight computer. Then there's the fact we test differently today because we finite element analysis every part down to the smallest component. That wasn't possible in the 60s.

> Because if we do it the same way we did 50+ years ago, we learn absolutely nothing and the whole thing is a pointless waste of money.

I would argue that if we did it exactly as we did back then that we would actually learn something because we forgot how to do so much. Literally can’t build an F-1 engine. It would take a ton of work just to recreate it.

However, the benefit is that we would then have plans (diagrams, specs, etc) to build it and one built we can iterate.

But building what we had is already a tremendous challenge because of the lost knowledge. Were it not for that, I would agree with you.

> However, the benefit is that we would then have plans (diagrams, specs, etc) to build it and one built we can iterate.

To me the current state looks like as if we

    1) recreated F-1
    2) had plans and diagrams
    3) iterated - first to the level of NK-33, then to the
       level of RD-270, then to the level of Raptors
    4) carefully put those original plans back on the shelf
       and forgot about them.

Yes we can't do F-1 today verbatim. We also can't do many other things, not easily - steam engines, telegraphs, airplanes, cassette players of the time would all require some re-engineering. We however can often do better using very different approach.

> However, the benefit is that we would then have plans (diagrams, specs, etc) to build it and one built we can iterate.

Hypothetically we've lost the diagrams,designs,knowledge to build a 386.

Is it worth building one today just so we can remember how, and then iterate on it?

No, absolutely not. The F-1 (and the 386) are ancient. Don't start from ancient and work up. Aim higher.

Sure you always learn something when you do anything.

> Literally can’t build an F-1 engine.

We can. There has been lots of work done on that already. But you wouldn't want to do an engine like it was done back then anyway. It would be crazy to do it the same way. A modern version would be better, better controls, lighter and so on.

> However, the benefit is that we would then have plans (diagrams, specs, etc) to build it and one built we can iterate.

Those would be more like constraints. So many things that are not the same anymore. You would literally reconstruct the economy from the 1960s first. That would be totally insane thing to do.

Its not because of 'lost knowlage' its because first of all, it just doesn't make any sense to do it the same way even if you could. Both the tools and the people are totally different, the structure of the economy is different.

I agree - there would be tremendous value in taking the 1960s approach, keeping it simple, and optimizing with modern electronics.

What they seem to be doing is a code rewrite while adding features.

Revival of Saturn-V today would likely be very expensive comparing to Starship variants.

It depends on your mission. If the mission is to go to the moon, well, we've done that, we don't really need anything new. If the mission is to reduce carbon emissions, that will require something new.

I think the fundamentally disconnect here is that its not 'the same' mission. Sure if you break it down to the extreme the mission to the extreme, its the same 'people on moon'. But if you think about it beyond that, Artemis makes quite a bit more sense.

> We are supposedly going to the moon in two years, but we have never attempted a cryogenic refuel in orbit (this seems like a biggie).

The 2024 date was always politics and its an open secret that it won happen. Everybody who has followed this topic kind of knows this.

> - Have many layers of redundancy. Apollo had 6-7 backup procedures for what to do if they couldn't launch the lander off the moon.

While true, its also the case that Apollo lander had 1 ascent engine that couldn't be tested and wasn't redundant.

> - Test. small tests, big tests, real tests, skin-in-the-game tests.

I think its strange that he points this out but then doesn't point out that this is exactly the testing Starship proposed to prove out the rocket and things like the Cryo transfer.

Think about it, we can go to the moon but now can't. None of the superpowercountries like China, Russia, EU, could. I give more credence to we never landed human there but only sent mechanical robots there for deployment to prove we landed there. Look up Neil Armstrong career after coming back from the moon. He was so wasted about his achievement...could have been senator or even some big corporation hotshot. But didnt. Nearly all moonwalkers behave the same. Either they have moon ptsd or as what conspiracy hinted, we never have human landed there.

> Either they have moon ptsd or as what conspiracy hinted, we never have human landed there.

You can read an autobiography book of Michael Collins, it answers your question to a some extent. He cannot say for every astronaut and I wouldn't risk to give here an answer in a short form as I understand it, because I'm not sure I understand it right. But I urge you to read and to answer your question yourself.

[1] https://en.wikipedia.org/wiki/Carrying_the_Fire