More Heavy Lift Thoughts

Rand

Great comments. For the past almost 20 years now the CATS crew continues to state that the golden age will arrive when we have a fully reusable launch vehicle (RLV) where the operating cost are marginally above the cost of fuel and amortization. I would posit that what we really need is an RSV, a reusable manned space vehicle that can carry humans between arbitrary orbits in cislunar space (any orbit between LEO and the lunar libration points) An RSV is much easier to build (fuel costs are high though, depending on whether it is brought from the Earth or Moon).

I'm thinking SSF means Space Shuttle Fleet? Or is it one of these? Please forgive my ignorance.

SSF = "Space Station Freedom," which was the name of the program back in the late eighties, before it became a Russian welfare program, better funded by the State Department.

Er...I don't honestly think the Golden Age of space is waiting on the transport system. Really, if the cost of transport to orbit were zero, what would that change? To be sure, there'd be a fair amount of tourism, for a while at least, until it became as commonplace as going to the zoo.

But what else? There isn't much evidence that you can do anything in orbit that you can't do cheaper and easier on the ground. It would certainly ease the difficulty of going to other planets, but then the same ultimate question arises: what present (not imagined future, such as He-3 mining for imaginary fusion reactors) economic activity can we imagine on the Moon or other planets that would pay for even much lower costs of transport than we have now?

I'm not trying to diss space travel per se. I'm an enthusiast from way back. But I think the 1970s-80s "space truck" "practically useful technology" argument was horribly flawed, and we should have stuck with the "national glory" and "personal pride" and "because it's there" kind of arguments that justify climbing Everest or breaking the world record in the 100m dash in the Olympics.

I think men should fly in space, go to the Moon, and learn to live on Mars, for personal glory and tribal (i.e. national) pride, to walk tall and beat their anthropoid chests and say look what we've done! But I think the argument that, once this or that technical obstacle is overcome, we'll find building on the Moon is an activity undertaken for the same reasons and in roughly the same way as building a new subdivision in Texas or new factory in Tennessee, is, at this time, simply not credible.

So we're focusing on two cost issues, construction and transportation.

While it's cheaper to construct on Earth, eventually we are going to have to develop the ability to do construction in space. Somehow the ISS example does not inspire.

I just want to see us moving forward. To me, that means design payloads for what we have, with the understanding that bigger is better and will come along in time.

I don't think this means I have a heavy lift fetish (not that anybody is claiming that.)

If a company wants to participate in space activities but doesn't have a heavy lift option, what prevents them from proposing options that they can support?

I think once we start opening up the high frontier flight rates aren't going to be a problem. Once we start putting bases and colonies off world, it will be a long time before we can launch enough to meet the demand. Especially if we just do it, colonize, one way. It's not just people, food and fuel that will need to be transported. It'll be power plants, tractors, machine tools and other heavy industrial equipment. At least initially, to give them the ability to create there own manufacturing base (for local consumption.)

If you can't send a tractor to Mars or where ever, you can send tractor parts and tools. That'll be enough flight rate for every size launch vehicle that exists.

Mars need soil. How big a rocket do you need for that?

Ok, maybe you send a chemist instead of soil, but they'll still need worms.

There's a lot of real estate out there. It's time to go.

Carl: "what present (not imagined future, such as He-3 mining for imaginary fusion reactors) economic activity can we imagine on the Moon or other planets that would pay for even much lower costs of transport than we have now?"

Once again, that isn't the point - except for the initial stages, in which even the enthusiasts think that we will need a (largely automated) mine and launch system on the Moon. Refining on the lunar surface is not necessary, for two reasons; it's almost certainly easier to do it in orbit and even the slag is useful for something - that something being reaction mass and ultimately the beginnings of soil for orbital habitats.

You are unnecessarily restricting the possibilities in your question, too. The most obvious, and easiest, application is power generation, and large scale solar power on the ground has never really been tried. Before anyone says that such an application requires the manufacture of megatons of solar cells in orbit; well, that would work, but the quick and dirty way is a heat-engine power plant (yes, sure, it would need radiators) and a BIG mirror. Which would need to be no more than a few microns thick, in space conditions. The waste heat would be dumped at close to absolute zero; it should be obvious, but all one needs to accomplish this is a sunshade - which again could be no more than microns thick.

Asteroid mining also has possibilities. A lot of asteroids are fairly pure nickel steel, with no refining at all, for example.

To return to your question and give my answer; with the exception of the answer I've already given, none. The planets are irrelevant. We need somewhere to live? Then we'll build it!

Er...I don't honestly think the Golden Age of space is waiting on the transport system. Really, if the cost of transport to orbit were zero, what would that change?

I'd be able to go. That may not be a big deal to you, but I've devoted my life to that cause. We'd also be able to afford to do a lot more planetary exploration, for those who get a kick out that. The National Geographic (or Planetary) Society could afford a Mars expedition.

I'd like to add to Mr. Christian's comment regarding automated facilities on the moon. It can also be generalized to include the on-orbit construction. Instead of sending trained astronauts, etc, etc (which was pointed out here or in the original post, to require considerable expense), why not train the astronaut-constructors here and keep them on the ground, and use something similar to a motion-capture rig as a teleoperated waldo, with robot/drone "workers" on-site? The benefits would be obvious, I think. An astronaut can then be sent to a station that's ready for immediate habitation.

I'd be able to go.

Yeah, me too.

That may not be a big deal to you

Geez, Rand, read what I wrote. I watched every Apollo launch, and sucked down Ben Bova stories of living on Mars like candy. I waited in a godawful two-hour traffic jam to see the Shuttle land at Edwards on its first flight after Challenger. I would cheerfully tear down about 1/4 of the Federal agencies and give their budget -- in what way I am not sure -- to national space ventures. I say go go GO.

But I don't fool myself that my reasons for wanting to go -- or wanting my nation to spend the public dough -- are so that my investment portfolio grows fatter, or to solve some niggling problem here on Earth that some random resource in space can solve.

Furthermore, I think harm was done to the cause by adopting a fairly transparently false face of practical utility on space development, of pretending to people it was all just focussed business and tech development which had all kinds of profitable application on Earth. I think people are OK with let's go because it would be AWESOMELY COOL to stand on Mars. They may not support it with tax dollars to the degree one wishes, of course, but, oh well, them's the breaks. I think overpromising (even overimplying) the plain economic benefits at home was a huge mistake in the late 70s.

To be fair, I don't know what else could have been done. That was a hugely effeminizing period in American history, when the entire country got deballed in all kind of ways. Detente, responding to the Afghan invasion with an Olympic boycott, even/odd gas rationing, Alan Alda in MASH replacing John Wayne in Green Berets, candlelight vigils on the 400th day of the Iranian hostage crisis, and so sickeningly on. The masculine traits of a love of adventure and daring were flung into contempt, and it was all about nurturing and practicality. I suppose in hindsight I'd argue it would've been better to submit to the budget cuts than submit to being personally cut, so to speak. Die like men. Yell this is SPAAAAAARTA while pushing Babs Mikulski into a 500-foot hole.

But...I dunno, I didn't have to earn my living in the field, and things are different if you've got to pay the mortgage and the kids' college tuition.

Carl:

Re: Economic activities

1. Raw materials. Iron, nickel, gold, platinum, you name it. The asteroids have millions of tons of useful materials that, with lower launch costs, would be cheaper to mine & refine in space than on Earth. Plus, the pure abundance is compelling.

2. Power (besides He-3). Solar Power Satellites. Power generation on Earth (whether Solar or more traditional) is a big industry that uses a lot of fuel and real estate. Lowering the cost of energy would be huge.

3. Manufacturing. Microgravity, easy vacuum, easy clean rooms, temperature extremes. This will make some forms of manufacturing a lot easier, or simply possible. For instance, some crystals crystallize differently in micro-g than under 1g. Almost very computer chip in the world starts with a silicon crystal, so other forms of crystals may spur other industrial purposes. Pharmaceuticals also form differently in space.

4. Real Estate. They aren't making any more of it. Some clever folk will find a use for it, even if it's just a Self Storage unit (you said $0 launch, right?).

5. Tourism. Say what you will, but I think the Moon is more like Mt. Everest and Disneyland than the Zoo. People will keep going back forever. Just because Sir Edmund Hillary did it doesn't mean that people have stopped. Teams go every year. Same for the Royal Venusian Cruise Zeppelins.

6. Science. With low enough transport costs research Societies and Universities would be able to maintain permanent presence on the Moon or further out. There's always a new generation of astronomers to educate who would benefit from a semester at the telescope array on the far side of the Moon, or young geologists who would love to write their Ph.D. thesis on the hydration patterns of Olympus Mons.

7. Crazy people like you, me and Rand. We don't need a rational reason to go. We're going anyway. We'll pay for it and we'll create value once we get there. I'm set on building a city among the clouds of Venus' upper atmosphere (1 bar, 0~50 degrees C, 0.91 g), personally, and I'll have to exercise a great deal of restraint to not name it Bespin.

I am in general agreement with Rand on the need for local assembly of space structures (probably the best thing to come out of the ISS project), however, I can't agree with him on the point of local assembly.

Oil Rigs are a flawed analogy because we actually do pre-assemble Oil Rigs, often thousands of miles from where they will be deployed. We then tow the completed, tested and fully commissioned rig into position to start operations. This is far more analogous to the Shuttle C ISS concepts.

The problem isn't that we need to pre-assemble, it's working out what the optimum mass and size for a payload that can be economically launched?

If that size and mass are two small then it doesn't matter how good our space construction techniques are because we'll never be able to practically launch the parts to build anything remotely sensible.

You couldn't assemble an Oil Rig or, for that matter, anything of any size, if you're limited to twice daily helicopter flights with a maximum cargo load of about 10 tonnes. No matter how benign or easy to work in the environment is.

Show me that you can build large and scalable space structures using modules than can fit into a cheap non-heavy lift faring and we can talk but without that... well... I suspect you'll be disappointed with the end result.

Brock your #7 rocks! ^_^

One does because one can and if one can't then one will try to change that to the best of ones ability.

working out what the optimum mass and size for a payload

Optimum mass is not the issue. The issue is do we wait or do we go.

If you design something too massive for current vehicles to lift you've chosen to wait.

If you choose a design that fits on current vehicles you've chosen to go.

Do you imagine the SpaceX Dragon is the largest vehicle they will ever launch? I don't.

I say, go now! Don't send people yet, send packages so that when people arrive they have their stuff ready to go. They don't have to carry everything with them.

Now, suppose we figure we actually do need heavier lift to send humans after their stuff... with all that stuff sitting there (and more in transit no doubt) you now have a greater incentive to make something work to get there.

Isn't that how government works? Do half the job, then go back and ask for more money?

Maybe included in that stuff is we have Elon send a Tesla Roadster to be the new Mars buggy? Now that's incentive!