If a shuttle trip from a planets surface to orbit costs "High" dollars; how much does a beanstalk ride cost? I'm thinking it costs Low. but if you're have a different opinion I'm interested in your argument. Also: if any of you can help me or point me in the direction to figure out the realative energy of aluminum-oxygen magnesium-oxygen and Hydrogen-oxygen rockets I'd really aprieciate it. It occures to me that Lunar shuttles probably use metal-LOX rockets because they're hydrogen poor. here's a cool link: http://www.wickmanspacecraft.com/marsjet.html