An Expensive Solution to LEO...

Status
Not open for further replies.
F

Floridian

Guest
The biggest problem for space exploration right now is conquering LEO. An actual space elevator appears to be generations away. Here's an idea, I'm sure if its 100% possible but I think it is...

A 60km-80km Pyramid (tall enough to escape 99% of the Earths Air resistance) composed of crystalline titanium/steel/another substance. Instead of elevators, the pyramid uses trains that spiral around it all the way to the top.The trains would be the most advanced possible. The bottom floors would be very large, perhaps the structure could be anchored by a mountain. After about 20 km, it would be impractical/perhaps impossible to build a large structure, at this point the structure would start to get a good deal smaller. At a height of around 40km, the structure would be shortened even more, focusing on only supporting enough weight to carry two train tracks, one going up and one going down. On the bottom levels, a road might be able to spiral around with the train tracks if the structure was large enough. This would greatly decrease the need for elevators on the bottom floors which would compromise the structural integrity.

At the top of the structure there would be a few different options, keep in mind that at this point though we are technically in space, we still trapped within Earth's gravity and have not achieved escape velocity:
A) A Launch Pad for launching Rockets, these rockets could simply accelerate into orbit, or could accelerate out of Earth's gravity well. Seems like a waste, but this would actually be very beneficial, we would not have to overcome air resistance on rocket launches and the crafts would not have to be as structurally sound.

Docking with the top of the structure would be tricky, but perhaps theoretically possible, perhaps similar to landing on an air craft carrier, as the craft passes the structure a hook and a cable are attached which slow it down and reel it in. Or, no crafts launched from the structure ever dock, they simply connect together at a 60 km orbit, they could form a structure there where supplies was sent, until at one point they could be launched into escape velocity.


The next part sounds very crazy but it might be possible to extend a thin cable from the top of the structure to a satellite/small station 30,000miles out. Sort of like an actual space elevator but not quite. Even if this cable was only strong enough to carry electricity, it would be well worth it.

Another option would be constructing a rail gun on top of the structure that fired satellites into orbit.


In any case, it would create a butt ton of jobs.

If this structure was possible, it would generate HUGE amounts of revenue very quickly. Governments, MNCs (Multinational corporations), and private investors could pool funds and each own a share of the elevator, sort of like owning stock in a company, but it would be mainly for distributing profits.


Other thoughts:
Perhaps nothing would need to come down the structure, instead objects could be parachuted down and the parachutes recycled.


Concerns:
Terrorism
Funding

This proposal is more of a capitalist solution rather than a governmental fascist/socialist/centrally planned solution to space, and in my opinion, much more feasible, the whole point is creating profit, and making it worth it. Which would bring in investment.

Solutions to Terrorism, for example - a plane crashing into the structure.
A) Isolating the structure, giving it a giant air space, very advanced radar tracking/anti-air systems.
B) Inter-governmental treaty against attacking the structure
C) Making the first 20km basically entirely solid, the point is not to use this as a building, the point is supporting the top.
A missile or a plane hitting a 20km tall and miles thick structure isn't going to do ****.


Oh, one more thing. I don't know if this would actually work, but, heres another method of launching objects from the top of the space elevator.

At the top of the space elevator (remember how there is no air resistance, well basically none), there could be a ring. This ring would be connected to the elevator in the center, it would spin around its axis. It could also slow down. Since the space elevator would be connected directly to the ground and powered by nuclear reactors/other ground-based energy sources, there would hopefully be enough energy to spin the ring to a high enough velocity to launch objects into orbit.

For example:
Trains take a cargo container up the space elevator.
At the top, the cargo is loaded onto the ring. The ring begins spinning and continues spinning until it reaches a speed where it can launch the object out into space far enough to escape gravity.
 
M

MeteorWayne

Guest
Yeah sure, an 80 km pyramid. That will be cheap! :lol: :lol: :) :D :shock:
 
F

Floridian

Guest
MeteorWayne":2cn7vcap said:
Yeah sure, an 80 km pyramid. That will be cheap! :lol: :lol: :) :D :shock:

If you weigh the possible returns, technically yes :). You are right though, it would be f-ing expensive. But remember, the entire world would be investors. It would create millions of jobs.
 
M

MeteorWayne

Guest
To me the idea of an expensive solution is just silly. We can't even afford a cheap method to LEO, so it seems pretty pie in the sky to me. But that's just me. Folks that will live another 75 years or so might consider that realistic :)
 
A

Astro_Robert

Guest
Actually, NASA has looked into what it would take to do a similar idea.

Since fabricating a tether for an elevator is difficult, NASA (at least I think it was them) somewhere once hypothsized about building something like a 30km (maybe it was only 3km, its been a while sinceI read the article and i'm having trouble locating it again) tower to attach to an elevator. The benefits would be similar.
- Decrease tether length (particularly the lower end through the atmosphere). The less stress on the tether due to length and wind shear the easier it is to make it.

I will try to find an article and post it later, I only seem to have an old powerpoint from NASA Institute for Advanced Concepts. A tower with an internal very high speed elevator would make much more sens than a pyramid with a train, but your heart is in the right place. A pyramid that is 60km tall might need to be 30kn wide at the base, that is an unimaginable amount of material.

The article I recall did discuss the challenges in the tower, and even wikki sort of referred to fixed base stations as saving a few kilometers of ribon length (and thickness). However, today's tallest building in the UAE is only 0.8km tall, so we have a ways to go yet. But then Arthur C. Clark did say when asked that he thought that Space Elevators would become a reality about 50 years after people stopped laughing, maybe he will turn out to be right.
 
N

neilsox

Guest
With the train spiraling up this should be cone, not a 3 or 4 sided pyramid. Ten kilometer radius at two kilometers above sea-level may be strong enough. We need lots of sub basements or the cone is likely to tip over 80 kilometers tall. Yes a large mountain can serve as the base. Elevators typically lift about 100 meters max then you change elevators = 800 elevator transfers to the top, makes the train look very attractive. Earth may not have enough titanium for such a structure, but it does have enough carbon, and we are learning to make cheap diamonds = stronger than titanium by both weight and volume. We can probably build it 120 kilometers tall, but it would take about 1000 times the annual gross domestic product of Earth = too expensive. Above the ten kilometer level, construction workers would need space suits. Neil
 
E

emudude

Guest
Considering the amount of garbage the globe produces each day, imagine if we could have that same output of strengthened carbon structures like diamonds...hopefully someday that will be possible. An interesting idea, after getting past the "are you seriously proposing this" point and seriously thinking about how it could be done :D .
 
S

seminone

Guest
There is another method for constructing a system that combines both proposals, i.e., your tall tower and that of the CNT tether systems.

There are several scientific papers including a very recent one by Prof. Quine at York University in Canada, that show that an inflatable tower can be built with existing materials and technologies, see http://www.spaceelevator.com/2009/09/ca ... lable.html. However, the one system I will mention is our own which is based also on current non-theoretical technologies. The system goes by the name of a SpaceShaft, see http://www.spaceelevator.com/2009/11/th ... .html#more.

The system was discussed at several conferences that are related to the popular CNT tether system, and we intended to compete at the games. However, it is not a candidate for the games since it does not fit the descriptions of a tether system.

With time, since I really have very little to pursue the endeavor, i.e. when financially possible, the calculations will be placed online for public review. For now just go to http://spaceshaft.org http://spaceshaft.org and keep visiting from time to time for the new pages.

by the way my apologies if the text above does not look good, since it is my first posting here and I have not experimented with the editor system of this blog
 
N

neilsox

Guest
I looked at your spaceshaft.org My guess is very optimistic CNT specs are required to get much higher than 15 kilometers. Alternately (with CNT not much stronger than Kevlar) the shaft needs to be tapered = getting a larger diameter with each section added at the bottom. 10 kilometer diameter sections might be needed to get the top to 120 kilometers which is barely LEO = low Earth orbit. The top is moving at about 1800 kilometers per hour due to Earth's rotation, which is much less than orbital speed, so a large 2nd stage is needed to get the payload to orbial speed. Neil
 
Status
Not open for further replies.