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Back in 1988, a Canadian scientist was commissioned by a 2nd world power to build a system that could be used for orbital launch 4 orders of magnitude cheaper per pound to orbit than what SpaceX can do.

http://en.wikipedia.org/wiki/Project_Babylon

It would have involved firing payloads out of a very large cannon, then firing a rocket onboard to circularize the orbit, so this is not for manned launch, but we should be able to ship bulk items like fuel, oxygen, and water this way.

Every time we launched the shuttle we took perfectly good fuel and burned it up in the atmosphere because we had no way to take the left overs from the external tank and store them in orbit.

We also burned up a perfectly good contamination free vacuum-proof hull the size of a 747 fuselage that was already 99% of the way in orbit. (External tank.)




Thanks for reminding me of that 'gun'. I was recently noodlingly around with the question "Can the Navy's rail gun launch projectiles into orbit?" [1] The production gun is expected to us 64 Megajoules. The challenge is that you have to impart all the energy you can before the projectile leaves the gun (because you then lose your source of acceleration) and drag (or air resistance) is proportional to the cube of the velocity. So the faster you try to make something go, the harder the air resists it moving.

Using the math from "Rocket Propulsion Elements" [2] it seems like for anything other than a needle shaped projectile it would not be practical.

[1] http://www.navytimes.com/news/2008/01/navy_railgun_test_0801...

[2] http://www.amazon.com/Rocket-Propulsion-Elements-George-Sutt... Pretty much everything there is to know about rockets that isn't classified.


Great post, but '2nd world' is not the right description https://en.wikipedia.org/wiki/Second_world


Actually, I know this and this wikipedia entry. It's hard to for me to classify Iraq. For awhile they were another totalitarian state with ties to the Soviet Union. For awhile they were more in the US orbit. I guess that would put them in the 3rd world, though economically they have been in a different class than the poorest 3rd world nations.

I was thinking of terming them a "second rate power."


Yeah - Sorry I know its a bit nitpicky, because "second world" is pretty commonly understood in this way (to mean "secondary power"/"partially developed economy" etc.) but although common it is really a bit of a misuse of a word that has a very specific original meaning and I thought its probably worth pointing out to people (not just you) where the differences lie.


I remember LOVING the "Doomsday Gun" movie when I was a kid. It was one of those that was on TV late at night and I watched it secretly long after I was supposed to be in bed.

Though you don't even need to look at what he did for Iraq, right? His first project launched projectiles into space for the DoD iirc.




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