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[Culise]

Ooh, and maybe it could implement space fountain compatibility, along with a launch loop system.  ^_^

[LordBucket]

Can a rail gun launch a space craft with a live crew of human beings without killing everyone onboard

Instead of using it for manned vehicles, why not use it exclusively for cargo, then use smaller craft for human transport? What's your goal? Building massive space stations that require large quantities of material? Or making space travel as common as air travel? A rail gun might be a good solution for some problems, but not so good for others.

[nekoexmachina]

As I understand the topic (badly), railgun is a giant electromagnetic field. Wouldn't the field itself be deadly for any alive stuff onboard?

[GiglameshDespair]

As I understand the topic (badly), railgun is a giant electromagnetic field. Wouldn't the field itself be deadly for any alive stuff onboard?

No.

Electromagnets mean that it uses magnetic fields created by currents f elctricity.

The electromagnetic spectrum is different - this contains the things that could be different i.e. gamma and microwave radiation, but is completely unconnected to railguns and would not be a risk.

[Culise]

I would consider that dangerous EM radiation is almost a non-starter, leaving aside the fact that it has little to do with railguns.  Because the passenger vehicle is essentially a hollow, air-tight, ferromagnetic slug (air-tight to manage the transition to space; ferromagnetic to be picked up by the railgun), it would be trivial to design it as a giant Faraday cage.  It won't help with static magnetic fields (which don't generate a electric current - thank you, Maxwell), but such a vehicle will be in a moving magnetic field due to the varying gradients caused by the rail gun in order to accelerate the vehicle in the first place.  Since a Faraday cage effectively neutralizes externally-forced electric fields within and vice versa, electromagnetic radiation from outside wouldn't get in once the cage neutralizes. 

By the way, if you're unfamiliar with Faraday cages, you've probably nonetheless seen one almost every day.  Any microwave oven contains one of these in order to keep the field contained while active.  That's the reason for the fine mesh in the window in front of them.  It's also why cell phones sometimes lose signal in elevators. 

[IronTomato]

PTW because dwarfy space travel

[Talvieno]

I'm more for a space elevator, personally. Maybe it takes a lot longer, but it requires far less material, and can not only boost you into orbit, but potentially even into Jupiter's orbit (or beyond, if you use a slingshot effect). It would take a lot less electricity, too.

[10ebbor10]

Space elevator from Earth to Jupiter? Seems a bit excessive. Of course, you can get there using low energy maneuvers, but that's spacecraft maneuvering, not using space elevators.

[Talvieno]

Space elevator from Earth to Jupiter? Seems a bit excessive. Of course, you can get there using low energy maneuvers, but that's spacecraft maneuvering, not using space elevators.

No, no. The "top" of the space elevator would of course be stationary over one fixed spot on the Earth's surface, and that far away, the earth's gravity wouldn't effect it as much - past the point of geostationary orbit, it actually takes less energy to go "up" than "down". With it so far away, and moving so fast, it would be able to launch ships away from the earth. Of course, we need a much stronger material than we currently possess to make sure it holds together, but it's completely doable. Well, in the future.

But yes, it's a bit extreme... about as extreme as a levitating tube that stretches into space.

[Sheb]

What? Now, it always take energy to move away from Earth anyway...

[Mr. Strange]

Space elevator from Earth to Jupiter? Seems a bit excessive. Of course, you can get there using low energy maneuvers, but that's spacecraft maneuvering, not using space elevators.

No, no. The "top" of the space elevator would of course be stationary over one fixed spot on the Earth's surface, and that far away, the earth's gravity wouldn't effect it as much - past the point of geostationary orbit, it actually takes less energy to go "up" than "down". With it so far away, and moving so fast, it would be able to launch ships away from the earth. Of course, we need a much stronger material than we currently possess to make sure it holds together, but it's completely doable. Well, in the future.

But yes, it's a bit extreme... about as extreme as a levitating tube that stretches into space.

Are you describing... a giant sling that uses earths spinning to launche spaceships? Because I like that idea, and may have to steal it.

[Talvieno]

Space elevator from Earth to Jupiter? Seems a bit excessive. Of course, you can get there using low energy maneuvers, but that's spacecraft maneuvering, not using space elevators.

No, no. The "top" of the space elevator would of course be stationary over one fixed spot on the Earth's surface, and that far away, the earth's gravity wouldn't effect it as much - past the point of geostationary orbit, it actually takes less energy to go "up" than "down". With it so far away, and moving so fast, it would be able to launch ships away from the earth. Of course, we need a much stronger material than we currently possess to make sure it holds together, but it's completely doable. Well, in the future.

But yes, it's a bit extreme... about as extreme as a levitating tube that stretches into space.

Are you describing... a giant sling that uses earths spinning to launche spaceships? Because I like that idea, and may have to steal it.

More or less precisely that... sort of.

A space elevator cable rotates along with the rotation of the Earth. Objects fastened to the cable will experience upward centrifugal force that opposes some of, all of, or more than, the downward gravitational force at that point. The higher up the cable, the stronger is the upward centrifugal force and the more it opposes the downward gravity. Eventually it becomes stronger than gravity above the geosynchronous level.

An object attached to a space elevator at a radius of approximately 53,100 km will be at escape velocity when released. Transfer orbits to the L1 and L2 Lagrangian points can be attained by release at 50,630 and 51,240 km, respectively, and transfer to lunar orbit from 50,960 km.[49]

At the end of Pearson's 144,000 km (89,000 mi) cable, the tangential velocity is 10.93 kilometers per second (6.79 mi/s). That is more than enough to escape Earth's gravitational field and send probes at least as far out as Jupiter. Once at Jupiter, a gravitational assist maneuver permits solar escape velocity to be reached.[29]

Look at that length... that's why I said it seemed a bit extreme. lol   Still requires less energy than a railgun. (Fun fact: The designs for the first railguns, in WWII, would've worked, but would've required enough energy to light up half of Chicago.)

[Mr. Strange]

And if that thing would be one giant rail gun accelerating the ship at maximun speed human body can survive the whole way to the top, it would be pretty fast. And that's before any onboard rockets or such.

[alway]

And if that thing would be one giant rail gun accelerating the ship at maximun speed human body can survive the whole way to the top, it would be pretty fast. And that's before any onboard rockets or such.

No. It's a space elevator. Literally an elevator attached to a cable.

[10ebbor10]

Yeah, I mean, if you're attaching rail gun systems to that the weight will very rapidly spiral out of control. Also, you're going to have to deal with effects if earth's geomagnetic field, which is annoying.