The Early Days of a Better Nation

Friday, February 04, 2011



Space Rockets

Going to space with rockets: path dependent locked-in fluke or inevitable result of technological synergy?

We report - you decide.

(Thanks to Jack Crow in comment to post below for pointing these out.)

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14 Comments:

Well, both articles have elements of rightness and of wrongness.

Both articles omit a crucial element in the development of the V-2 and of nuclear weapons during WWII. Each side feared that the other was developing the same weapon, and thus continued their efforts out of fear. As it was, they were developing different weapons. Nuclear weapons arguably ended the war early; V-2s were less effective than that.

It's true that large rockets plus nuclear weapons have a synergic effectiveness as a weapon system. If the purpose of your weapon system is large-scale mass destruction. Rockets do have other uses as weapons, which became worthwhile at, oddly enough the same time as the V-2 was being built: aircraft firing them at tanks, ships and submarines; ground forces firing them as a different kind of artillery that is less accurate than canons, but deliver a lot more explosive. What made rockets practical was a sufficiently developed chemical industry to produce the huge amounts of propellant they need, at a price that made building lots of rockets possible.

The production of an atomic weapon rests on large scale grinding and refinement of Uranium. For a strictly Uranium weapon, the method is to use centrifuges, which is to say, the same technology as a turbine. Turbines creating power to spin grinders which feed centrifuges. Water power, in massive quantities, was needed for the fleet of fuges. And so it goes.

This part is completely wrong. The Manhattan Project didn't use centrifuges for enrichment. It used calutrons, gaseous diffusion and thermal diffusion. (And, of course, plutonium, which was a completely separate production route.)
And none of those involve "grinding" uranium - neither do centrifuges for that matter. They use gaseous uranium compounds or ionised uranium atoms. Using the word "grinding" here destroys the credibility of the author.

And any left over is finished off by this drivel:
"The reality of the ballistic missile, is that even relatively short flights, reach sub-orbital space, and are a breath away from orbit."

A breath away from orbit. Right.

Really, you could go through that pointing out an error in pretty much every paragraph.
"The internet is a result of the space programme". His continual misspelling of everyone's names ("Hilter", "Stephanson"). Firebombing Dresden as the key to victory over Germany. The V-1 being driven by a turbojet engine. Empires being founded in order to secure overseas supplies of coal and iron ore. Making oxygen industrially through electrolysis rather than distilling liquid air. Describing a rocket engine as a "one-way turbine". The fuel cell being invented in 1932 (try 1838). The "first and only large scale use of rockets" being by Germany on the UK. Hitler turning to rocketry to evade Versailles Treaty limitations. V-2s being fired from Germany to England.

It's just painful to read.

Thank you, Ken. I don't know enough about the field to comment - but the underlying argument and counter-argument intrigue me (errors notwithstanding).

What made rockets practical was a sufficiently developed chemical industry to produce the huge amounts of propellant they need, at a price that made building lots of rockets possible.

I'm not sure about this, because a large and highly-developed chemical industry is also what you need to make large-scale artillery possible.

Thanks, John and ajay. Oh dear. I just scanned both quickly, quite early in a rushed morning, and put down the odd niggle to my own ignorance or stupidity (usually a good way to bet).

I am not quite seeing what Stephenson sees as the obvious alternatives to rocketry. There is of course a good argument that the existence of nuclear weapons generated far more investment in rockets than would have been the case otherwise. But why would the absense have led to more investments to alternative launch methods? Instead of simply less interest in space at all?

The maddening thing about this 'debate' is that there are a lot of holes to be knocked in Stephenson's argument, but the other guy does such a piss-poor job of it.

Alternatives to rocketry - I suppose he's imagining space elevators. Still don't have the materials with a good enough strength/weight ratio. James P. Hogan (I know, I know, but this from before whatever got him got him) argued that space-planes were getting close in the late 50s and everything got diverted into big dumb rockets by the space race with the Soviets.

On the other hand, no other method of reaching extreme altitudes was ever seriously advocated even before the Germans dropped their proof of concept on London.

>Alternatives to rocketry-

Is there something horribly wrong with catapults?

His commenters seem to know enough schemes, lots of nuclear missiles and launch loops and lasers and what not. Some people seem to have a nearly religious belief in space, and they feel almost cheated if turns out hard and expensive.

Perhaps Stephenson's argument can be turned around. The historic path of the early cold war created a situation in which space seemed easier than it really was, because of the massive military funding. And two generations later, people's expectations are still locked into the extrapolations from those days.

How would you get a space elevator into place without rockets? Even if we do make the magic radiation-proof material. Could you maintain it without rockets?

You can't build it from the foundations up into the sky, can you?

Magnetic slingshots combined with spacesails are the only combination I can see for avoiding any sort of rocketry (I would count ion engines as soft rockets). That would be so awkward getting high enough that you could unfurl a sail in time before you fell. Just awkward all round, come to think of it.

Neal Stephenson's article annoyed me as in all that lengthy argument he just states:

"There is no shortage of proposals for radically innovative space launch schemes that, if they worked, ..." It is clear to me why they don't get funded, they are as likely to work as my design using big magnets that I worked up when I was ten. The only reasons NASA is spending a few dollars on encouraging elevator technology are that, eventually, it will be useful for landing on small moons and it keeps the sensawunda going, making good advertising.

Looking on the bright side, all those new planets being found implies that there are an aweful big number of moons out there.

There's always Orion, of course. And various combo approaches like SpaceShipOne/White Knight, or Pegasus, or dirigible-lifted rockets (rockoons). And one of the most promising ones, gun launch plus solid rocket orbital injection. I suppose those are alternatives to _just_ using rocketry.

Zamfir, that you for this:

"The historic path of the early cold war created a situation in which space seemed easier than it really was, because of the massive military funding. And two generations later, people's expectations are still locked into the extrapolations from those days."

That has more than the ring of truthiness to it.

The point about turbines and the V2. The fuel pumps of the V2 were turbine driven.

Centrifuges. The Russians did use centrifuges as did Pakistan, ironically these were invented by a German engineer who had been captured by the Russians.

Does one not have to grind uranium first prior to reacting it with F to make UF6?

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