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The Lunacy of Artemis

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Re: The Lunacy of Artemis

#41

Post by qayxc »

fallingknife wrote: post #3

The real lunacy is using chemical rockets instead of nuclear thermal once the ship is in orbit. That could reduce the fuel requirements for an Earth - Moon transfer by 4x. And this isn't some sci-fi tech. NASA built a working engine in the 70s.

> NASA built a working engine in the 70s.

Kind of. No NTR has ever been flown and tested in space. The program achieved many milestones and got pretty far into development, but was cancelled 50 years ago due to budget constraints. It's always the last 10% that are the hardest in engineering and while NASA (as well as the Soviet Union) got 90% there, it would still have taken a few years (maybe just two) of further development.

The real lunacy is simply not being mission-driven. A true mission driven design would have used a simple, reliable option using proven and existing technology. Like non-cryogenic fuel for example.

Hydrazin might be highly toxic, but its beneficial chemical properties make it a much better choice for moon missions. Long term storage wouldn't be a problem and reliable proven engines already exist, too. In space (LEO and beyond), the toxicity doesn't matter while its use as a monopropellant makes it ideal for the ascend stage of a lunar lander due to reliability and simplicity.

Proven technology that existed for many decades - no new engines required, no complex refuelling in orbit (just send filled tanks into LEO and keep them there for later docking), cheaper, less risk, safer...

Re: The Lunacy of Artemis

#42

Post by codewiz »

Unkind quotes, but hilarious and probably well deserved:

"SLS looks like someone started building a Space Shuttle and ran out of legos for the orbiter"

"But on top of this monster sits a second stage so anemic that even its name (the Interim Cryogenic Propulsion Stage) is a kind of apology."

"the minds behind SLS achieved a first in space flight, creating a rocket that is at the same time more powerful and less capable than the Saturn V."

"And SLS is a “one and done” rocket, artisanally hand-crafted by a workforce that likes to get home before traffic gets bad."

"The rocket can only launch once every two years at a cost of about four billion dollars—about twice what it would cost to light the rocket’s weight in dollar bills on fire."

"Early on, SLS designers made the catastrophic decision to reuse Shuttle hardware, which is like using Fabergé eggs to save money on an omelette."

Re: The Lunacy of Artemis

#43

Post by dotnet00 »

GlenTheMachine wrote: post #37

One minor quibble: on-orbit refueling has been demonstrated, during the DARPA Orbital Express mission in 2006. Otherwise, if NASA issued stock, you should consider shorting it.

That was on-orbit refueling of hypergolic propellants, which is already done regularly on the ISS and is conceptually straightforward since you can just use bladder tanks to do the transfer without any special considerations.

What hasn't been demonstrated is on-orbit refueling with cryogenic propellants, which involve more considerations regarding thermal and pressure management. Technically the most recent Starship flight test demonstrated on-orbit transfer of cryogenic propellants (between two internal tanks), but of course doing it with docking still needs to be done.

Re: The Lunacy of Artemis

#44

Post by pdonis »

XorNot wrote: post #4

This is a criticism rooted in viewing the problem the wrong way. You can't compare a modern attempt at a moon landing to the Apollo program. It's straight up invalid. The Apollo program was a national prestige program, so successful we stopped going to the moon for ~49 years and counting. At it's peak it consumed 2.5% of US national GDP. We will never, ever , nor should we run a program like the Apollo program ever a…

> it's thoroughly dismissive of the political concerns which are the essence of the entire problem

No, it is quite correctly pointing out that political concerns are creating a lot of problems that shouldn't even exist.

> If we don't get there with a more sustainable approach, then there's no point going.

But the article's whole point is that this is not a "more sustainable approach". It's less capable than Apollo, for more money, without any compensating benefits. If that's what "political concerns...are the essence of the entire problem" looks like, then I agree that "there's no point in going"--meaning we shouldn't be doing Artemis at all if this is what it's going to look like. But of course the "political concerns" won't let that happen.

Re: The Lunacy of Artemis

#46

Post by andbberger »

nine_k wrote: post #23
fallingknife wrote: post #3

The real lunacy is using chemical rockets instead of nuclear thermal once the ship is in orbit. That could reduce the fuel requirements for an Earth - Moon transfer by 4x. And this isn't some sci-fi tech. NASA built a working engine in the 70s.

But it would constitute nukes in space in a breach of international treaties! Certainly a NERVA-style rocket engine is not a nuclear bomb, and a few nuclear reactors with known and tightly watched positions won't constitute a threat of a sudden nuclear strike. But the treaties were made at times when the principal parties, the West and the Soviet bloc, did not trust each other one bit, and rightfully expected sabotag…

the treaty prohibits weapons, not reactors...

Re: The Lunacy of Artemis

#47

Post by venusenvy47 »

xt00 wrote: post #15

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…

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

Re: The Lunacy of Artemis

#48

Post by codewiz »

codewiz wrote: post #42

Unkind quotes, but hilarious and probably well deserved: "SLS looks like someone started building a Space Shuttle and ran out of legos for the orbiter" "But on top of this monster sits a second stage so anemic that even its name (the Interim Cryogenic Propulsion Stage) is a kind of apology." "the minds behind SLS achieved a first in space flight, creating a rocket that is at the same time more powerful and less capab…

And another one:

"Costs on SLS have reached the point where private industry is now able to develop, test, and launch an entire rocket program for less than NASA spends on a single engine"

Re: The Lunacy of Artemis

#49

Post by dotancohen »

codewiz wrote: post #42

Unkind quotes, but hilarious and probably well deserved: "SLS looks like someone started building a Space Shuttle and ran out of legos for the orbiter" "But on top of this monster sits a second stage so anemic that even its name (the Interim Cryogenic Propulsion Stage) is a kind of apology." "the minds behind SLS achieved a first in space flight, creating a rocket that is at the same time more powerful and less capab…

Even the title is a creative jest, as Lunacy literally means "Looking at the moon" (via "Lunatic" which is someone who looks at the moon - Luna).

Re: The Lunacy of Artemis

#50

Post by dotancohen »

idlewords wrote: post #34
LargeTomato wrote: post #26

We are going to The moon for two reasons. First, we want to set up a more permanent base. Nasa refers to this as "we're here to stay" The second reason we are going to the moon so that we can put the first person of color and the first woman on the moon. That is explicitly an Artemis mission purpose. Only time will tell if either of these two missions were actually worth it. One more point > Early on, SLS designers m…

Note that the first reason you give is tautological.

Possibly, but it's not unique to SLS. People were jesting twenty years ago about the purpose of the Space Shuttle being just a vehicle to get to and from the ISS. And the purpose of the ISS? So that the Space Shuttle would have somewhere to go.
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