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The Lunacy of Artemis

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Re: The Lunacy of Artemis

#431

Post by hifromwork »

twothreeone wrote: post #424
strangattractor wrote: post #419

Earlier quoted context omitted.

More likely the problem is DBC (designed by congress). Where are those old Shuttle Boosters made? The Orange tank? There are 535 member of Congress of which 10 are engineers of any kind. Probably even less Scientist.

That's not on congress though. If a budget for the agency only comes with those kinds of political strings attached, the right thing for the agency would be to say "please keep your money, the US won't be going to Moon or Mars".

I'm not very familiar with how US politics works internally, but how would it play out in practice? My experience with my (admittedly flawed) government is that the head of such agency would be dismissed from his position, and a new - more amicable - one appointed not long after. Are the US different?

Re: The Lunacy of Artemis

#432

Post by dotnet00 »

williamDafoe wrote: post #422
dotnet00 wrote: post #359

Earlier quoted context omitted.

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.

Re: The Lunacy of Artemis

#433

Post by dotancohen »

thaumasiotes wrote: post #238
dotancohen wrote: post #198

Earlier quoted context omitted.

At the time that the word was coined, there was nothing that one could do with the moon other than observe it.

Considering the sense of the word comes from the idea that the phase of the moon affects people's minds whether they're looking at it or not, this is obviously false. You can look at the moon, you can look away from the moon, you can hide from the moon, you can worship the moon, you can love the moon, you can describe the moon... but the relationship actually being expressed was just "being affected by the moon". Loo…

Point being that Moon is the root of the word Lunacy as used in the title.

Re: The Lunacy of Artemis

#434

Post by HarHarVeryFunny »

chasd00 wrote: post #426

when the drama of Artemis started unfolding i remember thinking SpaceX ought to just go to the moon themselves. Iirc Falcon Heavy in a full thrust config already has the capability to get there they just need a lander and return. On the other hand, that effort doesn't get SpaceX closer to Mars and would be a pretty big distraction. Also, I imagine they want to play ball for funding purposes.

If SpaceX wants to put people on Mars, and get them back, then the moon seems a pretty good proving ground for things like a lander and ascent module, orbiter, etc, not to mention for any kind of habitat/etc they're planning for Mars.

SpaceX planing to land Starship on the moon (and take off again) seems like a complete non-starter. I expect NASA can get the rest of their useless program built given enough money, but if Starship needs arms to catch it even when landing on a smooth concrete surface, then how the hell does it expect to land on an uneven pile of soft lunar regolith, much less take off again?

Re: The Lunacy of Artemis

#435

Post by gnarbarian »

this is how our entire federal apparatus works these days. our government is profoundly broken but we lack the will to acknowledge it.

I have about 20 years of experience in Federal contracting.

we have nothing but process and zero accountability. It's literally a miracle anything ever gets completed.

we sink billions of dollars into projects that are forecast to have dubious economic benefits and then we never bother to see if it actually worked out the way the economics were justified.

empower programs and leaders to buck policy and regulations but make them accountable for failure of their core mission.

compensate leaders who save money by doing more with less.

etc.

Re: The Lunacy of Artemis

#436

Post by strangattractor »

hifromwork wrote: post #431
twothreeone wrote: post #424

Earlier quoted context omitted.

That's not on congress though. If a budget for the agency only comes with those kinds of political strings attached, the right thing for the agency would be to say "please keep your money, the US won't be going to Moon or Mars".

I'm not very familiar with how US politics works internally, but how would it play out in practice? My experience with my (admittedly flawed) government is that the head of such agency would be dismissed from his position, and a new - more amicable - one appointed not long after. Are the US different?

It usually plays out like this.

The Congress person from Alabama where the fuel tank is built refuses to ok spending for NASA's other projects (or some other desirable project that needs to get done) unless the design requires things be built in their district. Since the tanks were previously built there it becomes the easiest way to satisfy their black mail. This may not be explicitly stated other than in meetings with the speaker of the house but it is understood none the less. This is not Congress people directly profiting from this decision but they have to run for office every 2 years and need to have consistent pork returns to keep their constituents happy.

There is nothing illegal here in fact the system is pretty much designed to work this way to insure that Federal money is distributed among the states.

Re: The Lunacy of Artemis

#437

Post by jodrellblank »

rurp wrote: post #427
jodrellblank wrote: post #376

Earlier quoted context omitted.

Money isn't burned when spent on space programs. resources, e.g. fuels are, but money is spent, it stays down here on Earth, employing people, boosting corporate profits (and therefore pension funds and other things which invest in them), employing people (who maybe women and people of colour).

You could make the same argument about any government spending program, no matter how wasteful it is. The money always goes into the economy. The question is how to get the most useful output from that spending.

> "about any government spending program"

"hundreds of billions of dollars burned by space-billionaires" is what I was replying to. It would be more serious if the "burning resources" in the original comment's first paragraph meant fossil fuels, for example. Non-renewable things. Their second paragraph clarifies that they mean money (and not even taxpayer's money in their comment), which isn't burned.

> "The question is how to get the most useful output from that spending."

That is a question, not the thing I was replying to.

Re: The Lunacy of Artemis

#438

Post by bandyaboot »

idlewords wrote: post #79
dotnet00 wrote: post #59

Earlier quoted context omitted.

I think the point they're trying to make is that it looks the same for the sake of looking the same.

I was just trying to describe SLS visually. If you've seen a lot of Shuttle stuff then the initial resemblance is very striking.

The initial resemblance really just comes down to 2 fairly pragmatic design decisions. We’ll use 2 side solid propellant boosters and we won’t redesign them from scratch because they work. And, we’ll use the same foam insulation on the rocket that we used on the STS liquid propellant tank because it also works…furthermore, we won’t try to paint over the orange insulation because we know that that doesn’t work very well.

Re: The Lunacy of Artemis

#439

Post by rockemsockem »

thombat wrote: post #250
rockemsockem wrote: post #229

Earlier quoted context omitted.

Nixon cancelling Apollo early is what led to stagnation.

NASA had only contracted for 15 Saturn V stacks, and in 1968 declined to start the second production run. Nixon only assumed office in 1969, at which point the only question was how many of the remaining ten stacks would fly as part of Apollo. Under Nixon the final three Apollo lunar missions were cancelled, with one of those Saturn V stacks being used for Skylab instead. But even if all three had flown to the moon s…

I wasn't aware of those extra details! Very interesting.
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