Propulsion

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How are we supposed to get all of that stuff to the Moon?

ruveyn

apollo shuttles. unfortunately you are looking at ideas that are a long way into the future.
as long as it is cheaper to pull resources ou of the earth and that supplies the demand on earth, then we wont be having an moon trips. as it is we have arely scratche the surface with respect to mining. the deepest mines are only about 2kn deep and the earths crust is 40km and thats a hell of a lot of resources. it would be cheaper to dig up resources from 40km than it would be to get them from the moon. so, once supply and cost get too much on earth (and we are talking 100 years i guess) then they'll start moon programmes

Sounds like someone watches wayyyy too much science fiction programming.

Well, since you've admitted the Gauss means the most viable (read, the least science-fiction based), I'm bored enough to tackle the math.

First off, let's assume that we're going to be launching with the minimal distance between us and Mars: 57,936,384km.

Let's also assume, instead of just less than a month, you want to take a full month of 31 days. Doing this results in a necessary speed of 21.6km/s from the moment the ship has left the GPT.

To make it easy, I'll give you the g-force that would be experienced starting with an acceleration distance of 1km (neglecting the gravitational force of the moon experienced), so if you want the GPT longer, you can just divide the 1km's Gs by the new length to determine the new Gs.

Getting to 21.6km/s, I'm also going to assume a constant acceleration rate, since this will both make the math easier, and it will give us the minimum Gs experienced overall (having a varying acceleration would create lesser g-force at some points, but would require more Gs experienced later). So with a constant acceleration, the average velocity's going to be 10.8km/s. So this results in a time to travel the launch length of 1km equal 0.09246s. Using the equation V = A*t + Vo: Vo = 0km/s, A = V/t, resulting in an acceleration of 117km/s^2.

This equals a g-force of about 12,000 Gs. I sure hope you have some sturdy monkeys.

With this, you can change the depth required and, of course, the time you wish to spend travelling to the moon. Two months would require half the amount of Gs, three months a third the amount, and so on. But with length of time increased to the amount to make the Gs viable for humans to withstand, it renders this system pointless, so we'd better increase the length, neh?

Using the above math, if you increase depth of the GPT to 10km, that's 1,200 Gs and 100km is 120 Gs. At 1000km, you get a somewhat viable 12 Gs, but 1,000km is 2/7 the diameter of the moon. Building a GPT that long would cost trillions to quadrillions of dollars. Then there comes the issue of aiming it. Built into the moon, you're pretty much going to have just the one shot.

Are the taxpayers really going to spend that much money for a single shot that'll shave about a year over a trip launched using the current sling-shot method? And with this one shot, you have to make sure the damn thing's done by the deadline. In order to make sure you don't miss your single shot, you'll have to start building at least 50 years before the planned trip. Of course, you could hollow out a cone (an actual cone, not the semi-cones you're used to assuming is a real cone) into the moon to produce an ability to aim, but that only marginally increases your ability to launch, and would probably propel the cost into the quintillions of dollars.

This doesn't even include the issue of the energy required to accelerate the shuttle by such a means.

In other words, I'm hoping your post is a joke.

hey...how else can we ask questions, unless someone knows the answers?

I had this thought myself, only in the other direction. You build a cyclotron, which we already use to propel particles to half-light speed already. If you substituted a steady stream of matter, you could eventually get something moving at half-light speed.

WIth an infinite amount of matter to counterbalance the force needed to move the honkin' big mofo to that speed...

and an infinite amount of patience.. Still, I think the physics are possible, even if they're not cost-effective...


Still, we've already done something similar with ion drives...

Probably have to be something like the Yonadan asteroid on Star Trek...

There are working versions of Railguns and Coilguns but they just tear themselves apart, i guess the kinetic energy they produce in such a small length is just too much for the materials they are built out of.

Answer: Ion propulsion and making a "starwaltzer", a craft that travels at maximum velocity of 15 000 - 45 000 km/h but designed as a self-contained, self-sufficient colony in space. Takes a thousand years to get to Alpha Centauri (someone check my math) but we still get there.