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NASA’s Lunar Space Station Is a Great/Terrible Idea

spectrum.ieee.org

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Re: NASA’s Lunar Space Station Is a Great/Terrible Idea

#161

Post by dTal »

mytailorisrich wrote: post #84
Causality1 wrote: post #82

Earlier quoted context omitted.

No, earth is the best place to develop technologies to settle on another world. Planning a moon base when we can't even build and run a sealed biosphere on earth is like looking for sponsors for your F-1 team before learning how to drive a car.

Earth is a good place to develop and simulate but at one point we need to put this into practice and learn a lot in the process. To use your F-1 analogy: At one point you need to build and an actual car and to drive it on an actual track.

That "eventually" is much, much further away than where we are now.

I won't even begin to take a Mars mission seriously until there are permanent, sealed, self-sufficient bases in the Sahara, Antarctica, etc.

Re: NASA’s Lunar Space Station Is a Great/Terrible Idea

#162

Post by Retric »

rtkwe wrote: post #138
Retric wrote: post #131

Earlier quoted context omitted.

I am saying testing say crystal formation in space is only relevant for crystal formation in space. If that’s what you’re going to do aka manufacturing in space then sure experimenting in space is required. Getting the economics to look promising for actually manufacturing in space then that’s a separate thing. Aka Manufacturing would be that larger goal I was referencing.

It's not though the crystals are used to determine the structure of the molecule itself through XRay crystallography. We have to grow larger crystals that are then used to determine the shape of the individual molecules. Some crystalize easily and we were able to study them using crystals grown here on Earth but others were more difficult and had to be grown in space. Just because the research takes place in space do…

You can do that same XRay crystallography on the same substances on earth. Going to space is pure cost benefit analysis for growing crystals, not some exclusive experiment you can only do in space.

That said, when you get a massive subsidy by NASA, these costs are less obvious.

Re: NASA’s Lunar Space Station Is a Great/Terrible Idea

#163

Post by jessaustin »

manicdee wrote: post #150
jessaustin wrote: post #132

Earlier quoted context omitted.

TNSTAAFL. I think you're misunderstanding that equation? You're trying to get to orbit, so hold v and delta- v constant. Then you have the ratio of "wet" to "dry" masses constant. So the more you're launching, the more fuel it takes, and that is linear. I don't see how physics would work otherwise?

The ratio of wet and dry masses for a launch vehicle also depends on ISP, thrust, and aerodynamics. You can have an extremely high ISP and thus a lot of theoretical delta-v but you waste it all because your thrust ratio is below 1 and the vehicle can’t leave the ground. Over a certain size you can’t build up anymore and have to make the vehicle flat. This is because a certain surface area of exhaust nozzle can only p…

Yes of course rocketry is complicated. ITT we're discussing the specific question that parent raised: are a bunch of small-payload rockets more efficient than on big-payload rocket? We assume that actual engineers have done the work of designing rockets that actually reach orbit, whether small or large; that's why we assume equal velocities. Any particular orbit is characterized by a specific orbital energy. Tsiolkovsky certainly considers the effects of gravity; that's the point.

Re: NASA’s Lunar Space Station Is a Great/Terrible Idea

#164

Post by corebit »

avmich wrote: post #116
corebit wrote: post #95

Earlier quoted context omitted.

You mean... agile?

Sort of. Gateway looks like an example of how could we try to get to the Moon, but to do that not in a single Apollo-sized project, but splitting the task in easier chunks - and yes, incurring some overhead, but also opening up new opportunities. See, for Gateway we have much better TRL (technology readiness level) than for, say, short trips to the Moon surface, not to say about longer term Moon-surface activities li…

I agree entirely!

Re: NASA’s Lunar Space Station Is a Great/Terrible Idea

#165

Post by toss1 »

mulmen wrote: post #154
toss1 wrote: post #152

Earlier quoted context omitted.

Oddly enough, Nixon ran and lost against Kennedy in 1960. So for sure if Nixon had won in '60, there would have been no space program

Moon program maybe but the space program was already in full swing by 1960. Space was immensely important to Eisenhower for national defense purposes and Nixon was his VP.

Yes, of course, but your comment is quite off-topic. We were talking specifically about the moon program.

Obviously, launch & orbital vehicles are critical dual-use civilian/military technologies (space exploration & delivering ICBMs).

In contrast, visits to the moon are not (at least for the near & intermediate future) dual-use civ/mil technologies.

Nixon killed the moon program when he got into office, and it is very unlikely he would have started one had he won in 1960.

Re: NASA’s Lunar Space Station Is a Great/Terrible Idea

#166

Post by joquarky »

smaddox wrote: post #31
Mvandenbergh wrote: post #13

The thing about the original moon landing programme was that it had a great clarity of outcome and timeline. What: Land a man on the moon and return him safely When: Before the decade is out That meant NASA could really focus and throw out everything that wasn't directly on that path. Reusability - take too long, we'll build each craft from scratch. Permanent mission - Too complicated, keep the missions very short. M…

As far as I can tell, the primary purpose of manned space missions is to redirecting taxes to congressional districts and defense contractors. The secondary purpose might be to inspire interest in STEM, but it seems much less successful at achieving that objective.

What disappoints me is that we could be paying the same organizations to build things to expand space exploration rather than warfare.

Re: NASA’s Lunar Space Station Is a Great/Terrible Idea

#167

Post by rtkwe »

Retric wrote: post #162
rtkwe wrote: post #138

Earlier quoted context omitted.

It's not though the crystals are used to determine the structure of the molecule itself through XRay crystallography. We have to grow larger crystals that are then used to determine the shape of the individual molecules. Some crystalize easily and we were able to study them using crystals grown here on Earth but others were more difficult and had to be grown in space. Just because the research takes place in space do…

You can do that same XRay crystallography on the same substances on earth. Going to space is pure cost benefit analysis for growing crystals, not some exclusive experiment you can only do in space. That said, when you get a massive subsidy by NASA, these costs are less obvious.

You can't currently because we've not been able to grow sufficiently high quality crystals here on Earth with gravity. Basically anything that needs more than 30-60 seconds of microgravity can't be done anywhere on Earth no matter how much money you want to spend. NASA is already up there to learn about the effects on the human body (which again we can only really do holistically actually IN space) so trying to put the whole cost amortized over all the experiments isn't going to come up with a reasonable number.

But even beyond that this is precisely what governments are supposed to do, gather and distribute costs that would make little sense for individual companies or even massive conglomerates to do.

Re: NASA’s Lunar Space Station Is a Great/Terrible Idea

#168

Post by sprafa »

jdsully wrote: post #137
sprafa wrote: post #134

Earlier quoted context omitted.

He loathed Kennedy tho. He might have cancelled it, or changed it. Who knows really.

The Russians were working on the same problem and were so confident they refused Kennedy’s suggestion they do a joint effort. You can’t blame them either - they beat the US on every milestone except a manned moon landing. Any attempts to change the game would have been seen for exactly what it was: weakness. He may have hated Kennedy but he loved the US more.

True. I didn’t realize the Soviets thought they could do it? My impression was their whole lunar program was a clusterfuck
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