In a follow-up to the original Orion worship post:
The Saturn V, the biggest thing we've ever launched (just go with me here) weighed in at 6,699,000 lbs, or 3,350 tons, and managed to put a measly 100,000 lbs (50 tons) into lunar orbit.
So lets pretend we want to build a classic L5 space colony. How big does it have to be?
Sorry, but we're not going to "go with you there."
This is an inappropriate methodology, and the assumptions here are completely nonsensical. The problem has nothing to do with scaling Saturn Vs, and no one in their right mind ever thought that a "classic L5 space colony" would be built completely out of materials launched from the planet.
There is no good reason that we can't have launch costs of less than a hundred dollars a pound with chemical rockets, and give rides to millions of pounds of passengers and cargo. All that is needed is to make the investment into space transports, and set multiple teams of engineers loose on the problem, something that we have not done to date.
The cargo would be used to bootstrap production facilities for extraterrestrial resources, with high-value/pound payloads (i.e., electronics) coming up from earth. We do not need Orion to build space colonies. We need a lot of other things, but not that.
If there's no good reason, then why haven't we done it?
My Saturn V example was a tool for examining the problems with scaling. You're attacking the tree and ignoring the forest.
The mass has to come from somewhere. If you're talking the asteroid belt, then we still need to come up with a way to move the millions of tons of mass around the solar system. Are you seriously suggesting that chemical rockets are the solution for that?
If there's no good reason, then why haven't we done it?
Because there has been no perceived societal need for it. Space is not important.
There is no problem with scaling, if you use sensible vehicles, and not Saturn Vs. Or Shuttles.
Asteroids can be moved any number of ways. This discussion was about earth to orbit.
BTW, I'm hardly an Orion worshiper.
I'm well aware of the problems with the design, but at the same time I see a lot of unresolved problems with scaling chemical rockets into thousands of flights a year that people (including me) are wishing for.
Anon,
If you saw the six flights in the past few days of XCOR's operations and propulsion demonstrator for Lynx, you would not worry about scaling combustion rockets to thousands of flights per year.
Particularly if you assume more than one vehicle.
And what's the payload to LEO for the Lynx? Last I heard it was strictly suborbital.
Rand, just a question from a non-engineer:
What's the cost of the amount of LOX/h2 you need to put a human into orbit? (Just cost of fuel and his bodyweight, ignoring the weight and cost of any rocket)
I assume this figure would be the absolute floor of cost to orbit, right?
but at the same time I see a lot of unresolved problems with scaling chemical rockets into thousands of flights a year
Anonymous, I don't see this point. Chemical rockets scale quite well. Thousands of launches per year are merely a thousand times more frequent than a few launches a year. Sure you need to build a considerable quantity of manufacture and launch infrastructure. But I don't see the problem with building it.
What's the cost of the amount of LOX/h2 you need to put a human into orbit? (Just cost of fuel and his bodyweight, ignoring the weight and cost of any rocket)
Here are two very conservative numbers. A hundred pounds of propellant per pound of payload, and less than a dollar per pound of propellant.
And what's the payload to LEO for the Lynx? Last I heard it was strictly suborbital.
Yes.
What's your point? It's a rocket.
That article is also technically wrong.
The Saturn V put 100,000 lbs into a tranlunar injection orbit.
The payload to 300 miles (Skylab) was ove 240,000 lbs.
Even the Shuttle puts about that same amount of total payload (including the weight of the orbiter, into that same orbit (the Hubble delivery mission).
"We do not need Orion to build space colonies."
We don't - now. We might, if NASA succeeds in its mission of keeping mankind out of space for long enough. When the environment is sufficiently degraded, we are short enough of fossil fuels and there are enough wars going on because of all that; then we might get desperate enough to use Orion from the ground.
Let's not let it get that far, eh?
"When the environment is sufficiently degraded, we are short enough of fossil fuels and there are enough wars going on because of all that"
I just can't imagine spending my entire waking life constantly worrying about such idealistic flib flab.
When the environment is sufficiently degraded
Where do people keep getting this notion? It's like the Singularity, a straight line projection using the worst possible assumptions and ignoring technological and demographic change. We've already got electric cars being developed and sold. Hybrids are coming along nicely. Even if the Bussard Polywell doesn't work out there's still good old fission, and the waste (assuming no breeder reactors, which is, itself, an unlikely assumption) can be vitrified and dumped in the Marianas Trench for geocycling.
The world of Wall-E just isn't going to happen barring massive governmental and inter-governmental efforts to prevent better technologies from being adopted.
Jason:
Even if everything you say is true, there are still quite a few other problems that are not being addressed at all, or not being addressed anything like adequately. Aquifer depletion is one. Soil erosion is another. Deforestation and its accompanying loss of biodiversity is another.
Regarding the matter of soil erosion; I remember once seeing an article illustrating the scale of this particular problem. Somewhere in Kansas, there is a church with its associated churchyard, built about a hundred years ago in the middle of a flat plain. The area around it is farmed; the churchyard itself, naturally, is not. After that hundred years, the churchyard is now ten feet above the surrounding countryside. Ten feet of soil in a hundred years.
Somewhere in some tropical forest, there may be some obscure organism that is essential to life on Earth. We'll never know until we lose it.
There is serious concern about possible mass starvation caused by the fact that bees are dying in truly monumental numbers. Nobody knows why; but it's a fair bet that lack of wildflowers for them to feed on, and stress caused by amounts of pesticides not quite enough to kill them outright, have something to do with it.
It's not just about AGW. There are simply too many of us.
For the sake of laymen like me trying to follow the discussion, can you suggest a write-up that compares the Big Dumb Boosters (roughly speaking, Apollo, Ares/Orion, etc.) to fleets of reusables? If $100/lb is the number that would apply for an optimized SSTO reusable, what number would a BDB achieve under comparable assumptions? Thanks for the info.
For the sake of laymen like me trying to follow the discussion, can you suggest a write-up that compares the Big Dumb Boosters (roughly speaking, Apollo, Ares/Orion, etc.) to fleets of reusables?
Not really. For one thing, Saturn and Ares are not Big Dumb Boosters. They are Big Expensive Boosters. No Big Dumb Booster has ever been built.
But if you want a comparison to Saturn and Ares, they will never provide a hundred dollars per pound, or even a thousand dollars a pound (and they would never have a high flight rate, so a fleet of high-tempo space transports could put up much more payload).
"Somewhere in some tropical forest, there may be some obscure organism that is essential to life on Earth. We'll never know until we lose it."
Poppycock. If the Earth's biosphere were entirely dependent on one pivotal species in one place, it would have died long ago. Individual species go extinct all the time from entirely natural, Darwinian causes.
"There is serious concern about possible mass starvation caused by the fact that bees are dying in truly monumental numbers. Nobody knows why; but it's a fair bet that lack of wildflowers for them to feed on, and stress caused by amounts of pesticides not quite enough to kill them outright, have something to do with it.
It's not just about AGW. There are simply too many of us."
If you believe that the trees are producing invisible neurotoxins telling you to take your own life, seek professional help, urgently.
Rocketeer:
Nobody has to take his or her own life, or anyone else's for that matter. God will take care of that for us. All we have to do is not replace those that go - at least not all of them.
I remember the old Biblical command: "Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth."
OK. We have dominion, and the earth is replenished. The command was not "be fruitful and multiply until there are so many of you that there is no room for anything else to live". The replenishing bit is done. Let's quit already.
Incidentally, I happen to agree with the comment about using nukes and dropping the resultant waste in the Marianas Trench. Except that I have a better idea. Vitrify the lot. Pile it up in the middle of some otherwise useless desert, surrounded by a chainlink fence festooned with signs (in many languages) saying "IF YOU CROSS THIS FENCE YOU WILL DIE". Do nothing else. The result? We get rid of the waste, and if we need it or advancing technology makes it useful we can still get at it. And the average intelligence of humanity goes up fractionally. (This idea is not original with me, BTW.)
Ughh. Once the enviro nutjobs get on a tear, they won't shut up.
Back to the topic of discussion. Rand,you've been using versions of the same words, "there is no good reason", and "all that is needed..." for a decade on this issue and there's enough air in there to fit a Saturn V sideways. If you're unwilling to deal with the inflexibility of the existing market AS IT IS, then you're just talking semantics. Because who cares what COULD be done or what COULD BE NEEDED, if the existing market and world conditions are and for the forseeable future will be several orders of magnitude below what is currently needed to fund a true chemical RLV.
If you want a historical analogue (which I know you detest), who cares if the Phoenicians physically COULD have built massive reed boat fleets and traded with the Incas. Who cares if there was NO GOOD REASON the Romans couldn't have set up a colony in Cuba using the technology of dependable Roman sailing boats that ruled the Med for a millenium.
They didn't. It was too hard a technical nut to crack, and more to the point, market conditions didn't exist for them to even think of it much less try it.
That's where we are on rockets. At this point there's no lateen sail, no spice islands to head for for profit, and Hueng Cho's Ares I-V fleet is about to be shut down by disciples of the Goracle.
Maybe the situation will be different in ten years. But from here, I'm betting "only marginally, or perhaps even worse..."