NASA Still Wants Space Elevator

Jerry Smith writes "The Guardian reports 'Each of the groups that will gather in New Mexico is competing to win a NASA prize set up to encourage entrepreneurs to start development work on the technology needed to create a space elevator.' It still might take a while though, progress is slow, so slow."

Comments

What happens

[ClaraBow]

when a plane runs into the elevator? It only takes one crazy pilot.

Re:What happens

[legoburner]

Since carbon nanotubes are so strong, I would assume it would be sheared apart (see jet crashing into concrete.)

Re:What happens

[VoidEngineer]

it depends on what stage of construction the space elevator is at. the long term goal would be to build additional layers onto the elevator until it's a megastructure in every sense of the word, and it would be many times the diameter of a skyscraper. during the first 50 years or so, it would undoubtably fall apart if an airplane ran into it. after sufficient mass is added, even a 747 shouldn't really affect (in the same sense that airplanes occassionally fly into skyscrappers without knocking them down, ala 9/11...)

Re:What happens

[Alaria Phrozen]

I was going to pick on your math for the 99.999% thing, but that's actually decently accurate (at least according to the article). I thought satellites were much much closer to earth (600ish miles) but after a little research I found out those are the asynchronous orbit ones. For true geosynchronous orbit you need an altitude of 22,223 miles. Roughly 1/10th the distance to the moon! Space is a wee bit bigger than I thoguht ;-)

The one thing that does seem far-fetched is the several-thousand-mile-diameter-no-fly-zone-idea... isn't that a significant portion of the earth (neighborhood of 1% of the surface area)? Maybe I'm just tired, but these differences in scale are just insanely hard to get my head around.

Intermediate technologies.

[argent]

The same technologies used to build a space elevator from earth would be usable for building other things: space elevators for other planets, for one, since every body in the system that could use a space elevator has a shallower gravity well than Earth; inter-orbital elevators; rotating tether slingshots; ...

Re:Doubtful

[VoidEngineer]

Try reading 'Fountains of Paradise' to understand the scale at which the space elevator is envisioned. It's not an elevator in the sense you may be thinking of. The idea is to build an initial small elevator, and then use that elevator to lift extra mass onto the elevator itself, and to build up its size until it's a megastructure. The goal isn't to build an elevator with a single shaft that can handle 10 people at a time. The goal is more like having a vertical subway system that can handle a million passengers *per day*. Think of the New York City subway system... only vertical. *Thats* the long term dream/goal of people who are into the concept of the space elevator.

Re:If a space elevator is cheaper

[RsG]

There are several commercial launchers... Despite the subsidised national space agencies.

What do you think made those possible? All the first order research was done by NASA, or it's counterparts, decades ago. Without that hard work and "wasted" money we would neve have developed the requisite launch technology.

What do you think a space elevator will use, fairy dust? It will consume vast quantities of energy both to build and to operate.

In terms of energy losses, the elevators are generally accepted to be more effecient (admittedly this is theoretical).

It takes enourmous amounts of energy to put anything in orbit. Period. Future technology, in whatever form it takes, will face the same physical limits.

Rocket fuels aren't cheap, and aren't going to get cheaper. Moreover, rockets have a very low weight limit - those commercial launches you mention put up tiny satellites, and even then they cost through the nose.

Show me the advanced launch tech that can put something heavy in orbit today. Oh, right, it's that model of effeciency the space shuttle. Trust me, if that's the cost per pound that a space elevator has to beat, we could make it out of pure gold and still come out ahead.

We don't have anything that can do what a space elevator can. Unless you can show me an example of a launch system (existing or theoretical) that can carry the same weight, then your arguement that "by the time we can build the space elevator, we'll have better tech", is invalid. Seriously, go take a look at stuff like the X-prize craft - these are the "spaceships of tommorow" and they still carry very little payload, to no higher than LEO, for a hefty price.