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I think we all can understand the situation here unless people are really dense.. the Artemis program was setup at a time when the private space companies were still very new. SpaceX will soon be quite close to technically doing the entire mission themselves without Artemis at all. SpaceX took the money from NASA to help fund their Starship development and probably for other reasons as well. Net result is that by the time Starship can land on the Moon, they can basically do the entire mission without Artemis. So Artemis would be pointless.

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> I think we all can understand the situation here unless people are really dense.. the Artemis program was setup at a time when the private space companies were still very new.

SLS's design and shuttle-derived components were basically stipulated by Congress, specifically representatives from states where these shuttle-derived components are built and tested.

The goal here is to achieve something, yes, but doing so with billions spent in specific states is a large part of it as well. These representatives and senators also tend to still be loudly skeptical of commercial launch providers like SpaceX despite their successful track record, likely for the same reasons.

They also suppressed propellant depot work.

Yep. Even taking SpaceX off the table, we could have built a lunar program based on existing launchers like the Atlas and Delta class of rockets, using smaller modules docked in orbit, and orbital refueling.

Instead we have a giant rocket that costs billions per launch whose only purpose is to launch Orion to the moon in one shot, and it can't even deliver Orion to a conventional lunar orbit.

So the Artemis part of the program (the "pension plan") is just doing something that pretends to be marginally useful for insane amounts of money to secure political support through the jobs it enables at various companies strategically spread across the US (plus support from the international partners involved), while the hope is that the HLS part of the program (the "lottery ticket") will eventually succeed in making the other part redundant?

But still, I think the article has a point when it describes the difficulties of landing Starship on the moon and being able to lift off again several days later. Landing a rocket on its tail is cool when the only consequence of a failure is not being able to reuse the rocket, but when there are human lives in the balance, it starts to sound really scary. Not to mention the possibility of damaging an engine during the landing or of fuel loss preventing them from lifting off again...

It's a fair point, but the only way at all to land on a body that has no atmosphere is to use rocket engines that point down. The Apollo Lunar Module landed on its "tail", though it did at least have a separate ascent stage with its own engine, so might have had some chance of taking off again if the landing was damagingly hard.

I would argue plenty of lander designs (including LM) were tailless and landed on their butts! That should be easier than the balancing act of standing on the tail.

The point is more that compared to prior landers, the Starship version at least has a uniquely high center of gravity over a narrow base, which makes it a whole lot easier to tip, and amplifies the consequences of, say, leg damage.

The center of mass should be pretty low relative to the height of the lander, the engines and propellant are the heaviest parts, the engines are obviously at the bottom. The heaviest component of the propellant is the LOX, which is also at the bottom.

This is false most of the fuel is gone by the time it lands and most of the payload is up high that's why the latest designs for starship have diagonal thrusters 2/3 of the way up the rocket so they can stabilize the top heavy part of the rocket without having to control it from a high moment arm

Starship carries ~1200t of propellant, of which ~950t is LOX, and 250t is Methane. While yes, most of that will be burned off by landing, it'll still need enough to return to lunar orbit. Even if we assume that only 10% of the fuel is needed to return to orbit, that's 95t right on the bottom with another 10t of engines and most of the 100t of dry mass of the Starship itself (plumbing, tank domes etc).

The thrusters you're (probably) thinking of are the landing thrusters that NASA thinks they might end up needing. Not to stabilize the rocket when on the ground, but because the Raptors might be too powerful and might dig out a crater underneath the vehicle when landing on an unprepared surface (such as the Moon, at least before a base is established or something is sent to prepare a proper surface). Placing weaker landing thrusters up top eliminates this issue, although at the moment they're still considered speculative in the sense that last we heard (which was admittedly a year or two ago), SpaceX are not convinced that this will be an issue.

Thrusters would anyway be a crazy approach to preventing a crewed vehicle from tipping over, as you wouldn't want them to be firing when the crew are doing any of the things that would involve the ship becoming potentially unstable (eg unloading cargo). For stability they'd have to use the large self-leveling legs from the original HLS design.

You are confusing the issue here.

Imagine a world where Space X does not exist - never did.

Even still, Artemis is a terribly designed rocket that costs gobs more than Saturn V and performs much less.

Would you be happy buying something today that costs more than it did in 1970 and performs worse?

It doesn't matter what else is going on in the world, Artemis is shit.

SLS is the rocket. Artemis is the project that uses SLS, Orion, and Starship to land humans on the moon.

There's also the dubious Lunar Gateway concept although that will likely get dropped as reality sets in. Maybe the same will happen to SLS. Wishful thinking.

I think it's interesting you didn't even address my point, you just went straight for pedantic naming conventions.

To be clear:

SLS is shit. It is waaaay more expensive, heavier and less performant than Saturn V, Starship, etc.

Orion is shit. It is heavier, more expensive and wasteful in many ways than it needs to be. It's already old by this point too.

The Lunar Gateway is shit. It's a solution looking for a problem, and everyone knows it.

People seem to miss the forest for the trees here. The goal is to get a base on the moon, and this is the first step. Starship will eventually be bringing lots and lots of cargo to the moon for this purpose. Bringing people there for a few days and then bringing them back is a very short term goal.

I don't think there is any plan for a roundtrip Starship lunar mission. I think it is too heavy to get back.

> I don't think there is any plan for a roundtrip Starship lunar mission.

There are currently no official NASA plans to do so. In part because if there were that would be NASA tacitly giving up on SLS and Orion, which Congress would never support.

We'll see what happens if SpaceX ever advertises such a capability.

> I think it is too heavy to get back.

There are a number of architectures that have been proposed that should work. From what I recall, all of the involve using multiple Starship vehicles going to Lunar orbit.

> the Artemis program was setup at a time when the private space companies were still very new.

This is completely orthogonal. If it weren’t, the lander would be in a better shape, but it’s as much of a clusterfuck as the rest of the mission.

SpaceX has never been outside of LEO, and I’m very unconvinced Starship can do it’s part on Artemis, much less do all the mission by themselves.

SpaceX’s Starship allegedly needs up to 12 additional Starship launches to refuel the lander after getting into orbit so it can complete the mission. SLS can get from the ground to the moon and back with just the one rocket.

I don’t think it’s clear that SpaceX can “do it by themselves” any time soon, they haven’t done an entire mission yet, of which the lunar lander Starship is only one small part of.

Artemis is a dumpster fire of a NASA mission but like all of it is, including Starship.

SLS cannot get from the ground to the moon and back with just the one rocket. Orion is too heavy to land and return from the Moon. That's why the plan, even before Starship's involvement, was to transfer from Orion to the lander in lunar orbit, either directly or via the Lunar Gateway spacestation.

I understand it didn’t land on the moon but it flew to the moon and back (which is what my comment was saying) in 2021. The mission wasn’t perfect but their half of Artemis was demonstrated. Starship has not yet shown to be capable of completing its half.

Artemis 2 and 3 should be delayed until NASA can fix their shit.

> The mission wasn’t perfect but their half of Artemis was demonstrated.

Sort of.

The first fully functional Orion will be debuted on Artemis III. As an example of the differences, the Artemis I Orion didn't have functional life support systems. And the Artemis II Orion won't be able to dock with anything.

SLS does not fly "to the moon". To put it simply, it flies near the moon and back. Saying it flies "to the moon" it like saying that getting on a plane that flies over Orlando FL, lets you take pictures out the window, and then flies back home to your starting airport is "going to Disney World".

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