Highlift Systems' Space Elevator In The News Again

Kris_J writes "Highlift Systems may have found a second location for the anchor of their space elevator -- Perth, Western Australia. Apparently we have the calm waters and international airport that it needs, amongst other things. Slashdot has covered this company's efforts before: Oct 9, 2002 and, earlier, August 13, 2002, but it's worth discussing again since '[recent funding] has been given momentum by the Columbia shuttle disaster.'"

Comments

Question

[KeatonMill]

This is probably a stupid question, but why wouldn't inertia rip it apart? The way I see it happening is as follows: The bottom of the elevator is firmly anchored to Earth and the top is floating in space. The bottom is anchored so its movements match Earth's. The top, however, is so high up that it lags behind a bit and bends the whole elevator. Eventually, the material weakens and bends enough that the Earth pulls it down gravitationally and breaks it in two.

Also, could this possible create drag in the solar wind and slow the Earth's rotation? (most likely another stupid question)

you slack or stupid?

[QuantumG]

Simply read the docs:

The simplest explanation of the space elevator is that it is a cable with one end attached to the Earth's surface and the other end in space beyond the geosynchronous orbit (35,800 km altitude). The competing forces of gravity at the lower end and outward centrifugal acceleration at the farther end keep the cable under tension and stationary over a single position on Earth. This cable, once deployed, can be ascended by mechanical means to Earth orbit.

Which just goes to show, if you're asking on Slashdot, then you're either too lazy or too stupid to find out yourself.

Just the opposite

[roystgnr]

This is why most designs count on the bottom of the elevator touching the ground, so that a significant portion of the elevator's weight can be supported by contact with the earth instead of tension in the elevator.

First of all, the tendency to buckle makes it vastly more difficult to build a long structure under compression than one under tension. Building a structure to support the elevator from below would be just like building any other skyscraper; you wouldn't get the top of the section under compression to be more than a mile off the ground, and after that you'd still have 25,000 miles to go.

But perhaps just as importantly, the bottom of a geosynchronous elevator design needs to touch the ground because it needs the base to be pulling down on it, not lifting up. If you want to take a 20 ton payload up the elevator without pulling it down, then the elevator is going to need to be under at least 20 tons of tension at the ground when there is no payload on it.

Lack of Imagination?

[mamahuhu]

I'm appalled at the lack of imagination shown by most of these posts.

First off if you read the PDF (15M) report to Nasa prepared by Bradley C. Edwards to satisfy the requirements of his $500 000 grant you will readily see that this is totally feasible.

Next check out the website - where they are calling for people to express interest in working on this project. They expect to be hiring in the next year or so. You'll also see that serious people are taking this seriously. Do you want a job?

Next understand that $17B is not very much money. Considering that BP just spent $6.7B on a oil company in Russia and has plans for more purchases.

I meantion BP because they have a plan to move beyond oil.... BP Solar is BP's attempt to become a broader energy company (check out their new sun logo) instead of an oil company. The High Lift systems news page says: -

BP Solar - a subsidiary of British Petroleum, currently doing $300M in annual sales. Our discussions have focused on BP's interest in using the SE for deployment of a solar energy satellite. Several items that came up included possible collaborative efforts, the performance of our system and the possibility of BP using our system. They are considering writing a letter of endorsement

If BP with the cash they have can throw $6.75 B at Russia they could, over 5 years, finance a large share of the Space Elevator. Who needs the Government? In fact Nasa would make sure it costs more to build than it should. Nasa is a bureaucracy, not a business, and is ill-suited to the sort of cost control required of economically viable business decision. Only communists would argue that a Space Elevator should be built and controlled by government.

What would BP Solar do? Build Power Sats....

These are High Lift's vision for the main use for the Space Elevator. Imagine a fleet of these beaming power to anywhere on earth. Every country on the planet could get cheap electricity without the huge national grid infrastructure required now. Without the huge investments in time and resources to build power stations - and without the fossil fuel use.

Use your imagination.

These ideas have been the subject of SF for decades - but the Space Elevator is now possible due to those nifty Carbon Nano-tubes.

When your imagination focussed by the reality of this thing actually being built in the near term (5 years) everything changes - and it'll change for us not our children. It'll change our careers.

Imagine this - an electric airplane that is powered by a Powersat beaming microwaves to it. No fuel to carry, super efficient travel - and at what speeds?

These guys are planning for the Space Elevator to be operational SOON - they have realistic timelines.

What I want to see here is some discussion of the uses that could realistically be made of a space elevator. We're the generation that will built it, use it and be changed by it. I like the parallel to be made with electricity, or flight, or the steam engine - in the early stages everyone probably dismissed it - and the world changed despite them.

What would you realistically (with a nod towards economic viability) do with the low launch costs they're projecting - $10/LB...

Ideas anyone?