Space Elevator – Science Fiction or the Future of Mankind?

I personally think the accurate if sadly rather silly named space fountain might be the way to go myself, but still, a brief but elegant synopsis of what might be the future of space-travel one day.

What is a space fountain, you may ask? Well, luckily SMBC recently covered the subject with their usual grace and dignity.

Source.

Comments

[SolangeEggbert]

Space fountain is unfortunately utter, utter bollocks.
A space elevator in principle just requires a several-fold better tensile strength than we've managed to achieve in bulk in a cable.
Space fountain requires reliable massive linear accellerators handling massive amounts of power, as well as other difficulties.

[Bomarck]

So, I am assuming the pellets would be launched as needed instead of the orbital sandblaster that is shown in the comic?

[Lord Of Dorkness]

3857188

Completely true, a space fountain is sadly a high maintenance structure, while a space elevator requires more exotic materials but is lower maintenance. It's quite the big but interesting trade-off in theory, but one that probably would come down to nobody wanting to even risk their multi-billion dollar investment getting ruined by a power-outage.

I do however admire the elegance of the concept, compared with the more brute-force way of basically putting a giant string in orbit.

[Lord Of Dorkness]

3857204

Constantly active, actually.

The comic does however neglect to mention (but does show if not to scale) the two vacuum towers near the base that , meant to both reduce drag on the pellets and protect the magnetic equipment.

Think two giant 'gun' barrels that extends from ground level to the edge of space. Requiring materials that are still exotic by today's standards, but not as extremely exotic as the materials needed for a safe space elevator.

So a fascinating concept, but sadly one of those things that will probably be completely unpractical by the time we actually have the tech to build them.

[Keris]

Didn't hear about a space fountain before but the concept isn't bad, it just would use up a lot of power for keeping it stable because you would need to keep those particles running, when going for the same height as a space elevator it would probably be somewhat more cost intensive, but in comparison to the SE it would be currently build able.

The whole space exploration thing went dormant to the public for decades until 'recently'.
I guess its much more easy for governments to explain that they spend an extreme amount of their incomes to secure their own and take others resources with expensive but shiny weapons than to say "lets simply put that money into space R&D to find and grab some of that stuff out of the infinite expanse above us", because things are not worth anything if you haven't taken it from someone somehow, taking unclaimed stuff is like cheating.

[billymorph]

Check out something called a Lofstrom Loop if you want a cool alternative to either. It's one of those ideas that looks insane when you first glance at its heart it's somthing that we could do with current tech, though the scale is titanic.

[KMCA]

How do you keep said pellets on course on the way down? To me it sounds like they'd be lacking the insane velocity required to be unaffected by stuff like extreme winds.

[Lord Of Dorkness]

3857935

Sounds cool. I'll look into it.

3857490

Went into it above, but in short big honking vacuum towers that clears the atmosphere.

So... yeah, not exactly a ship in a bottle, as far as scale goes. Titanic really is a good word for it.

[wlam]

Why can't it be both? The problem with conventional space flight at this moment is that it's simply economically unfeasible. Even if there are unimaginable amounts of resources available throughout the solar system, the prohibitive cost of putting even one vessel into space makes any potential return on investment just not worth it. A space elevator (or analogous structure) is not only a massive improvement in terms of practicality and safety, it's a necessity if space travel is ever supposed to become anything even near casual and a larger part of our economy. As it is, it will never be more than some superpower's scientific pet project.

[Lord Of Dorkness]

3858359

Why can't it be both?

This one is actually really simple:

upload.wikimedia.org/wikipedia/commons/f/f8/World_map_with_equator.jpg

There's only so much room at the equator, many of those countries are economically and/or politically unstable, and all these structures are such massive undertakings that building one that works at 70-80% simply isn't feasible.

Brazil could one day be a real player in that field, but right now their space program is playing catch-up due to stiffing during the cold war.

But, yeah, I totally agree. Unless some new type of propulsion system is figured out, space elevators are probebly going to be the more efficient way of getting into orbit for a long, long time.

[wlam]

3858387
Science fiction and necessary future infrastructure, I meant. I don't really know enough about the engineering background to have any idea what the scales involved really are.

But yeah, as far as I'm aware, propulsion methods aren't really the problem so much as the sheer energy expenditure of lifting massive objects into orbit. As it is, the only way to actually do so is through self-propelled vessels, which have a limited carrying capacity, their own mass and a necessity for fuel, which lowers the margins involved even more. The simple overhead involved with lifting even the smallest thing into orbit just limits even the possibility for orbital assembly enormously. Raw materials, finished parts, bulky containers, all of it enormously heavy and all of it hideously inefficient. A space elevator would be the difference between taking a staircase and airlifting people with a helicopter every time they need to get to the fifth floor, basically speaking. The infrastructure and lifting capability is already halfway where you need to go and there are just much fewer moving parts involved.