Take the Elevator to Space.

mike65

Well it makes sense when you think about it.

This from Arthur C Clarke in [url=www.timesonline.co.uk/article/0,,1072-1794500,00.htmltodays[/url] Times.

In 1969, the giant multistage rocket, discarded piecemeal after a single mission, was the only way of doing the job. That the job should be done was a political decision, made by a handful of men. (I have only recently learnt that Wernher von Braun used my The Exploration of Space (1952) to convince President Kennedy that it was possible to go to the Moon.) As William Sims Bainbridge pointed out, space travel is a technological mutation that should not really have arrived until the 21st century. But thanks to the ambition and genius of von Braun and Sergei Korolev, and their influence upon individuals as disparate as Kennedy and Khrushchev, the Moon — like the South Pole — was reached half a century ahead of time.

If Nasa resumes lunar missions by 2018, that timing would be just about right: it will be only a year short of the 50th anniversary of Neil Armstrong’s famous “one small step”. But banking on solid rocket boosters to escape from Earth, as being planned, will not represent a big technological advance over the Apollo missions. Even if the spacecraft are reusable, it will still cost hundreds of thousands of dollars to launch every kilogram into space. I think the rocket has as much future in space as dog sleds in serious Antarctic exploration. Of course, it is the only thing we have at the moment, so we must make the best use of it.

But I would urge Nasa to keep investing at least a small proportion of its substantial budget in supporting the research and development of alternatives to rockets. There is at least one idea that may ultimately make space transport cheap and affordable to ordinary people: the space elevator.

First conceived by a Russian engineer, Yuri Artsutanov, in 1960, it was reinvented by a group of American scientists a decade later. And it’s based on a simple — yet daring — concept.

Today’s communications satellites demonstrate how an object can remain poised over a fixed spot on the Equator by matching its speed to the turning Earth, 22,300 miles (35,780 km) below. Now imagine a cable linking the satellite to the ground. Payloads could be hoisted up it by purely mechanical means, reaching orbit without any use of rocket power. The cost of launching payloads into orbit could be reduced to a tiny fraction of today’s costs.

The space elevator was the central theme in my 1978 science-fiction novel The Fountains of Paradise (soon to be a Hollywood movie). When I wrote it, I considered it little more than a fascinating thought experiment. At that time, the only material from which it could be built — diamond — was not readily available in sufficient megaton quantities. This situation has now changed, with the discovery of the third form of carbon, C60, and its relatives, the Buckminsterfullerenes. If these can be mass-produced, building a space elevator would be a completely viable engineering proposition.

What makes the space elevator such an attractive idea is its cost-effectiveness. A ticket to orbit now costs tens of millions of dollars (as the millionaire space tourists have paid). But the actual energy required, if you purchased it from your friendly local utility, would add only about a hundred dollars to your electricity bill. And a round trip would cost only about one tenth of that, as most of the energy could be recovered on the way back.

Once built, the space elevator could be used to lift payloads, passengers, prefabricated components of spacecraft, as well as rocket fuel up to Earth orbit. In this way, more than 90 per cent of the energy needed for exploration of the solar system could be provided by Earth-based energy sources.

I first read about this in the July 1979 editon of Future magazine also written by Clark. It seemed a brilliant idea then and it still is.

http://en.wikipedia.org/wiki/Space_elevator

Mike.

Capt'n Midnight

Here is what NASA should be looking at for the lunar mission -
ONE launch with existing materials and they have a way of dropping stuff to the moons surface. Using rockets to land stuff on the moon means that you have to allocate about 50% of the mass of the lander to fuel to slow you down. With a lunar elevator you can halve the amount of weight you need to carry out of the earths gravity well. The savings on the return trip are in the order of 4:1 since you save fuel both ways. It can't be used for people since it's too slow - but the vast majority of stuff you need to transfer to the moon can be sent up early.

http://www.universetoday.com/am/publish/lunar_space_elevator.html

The advantage of connecting an elevator to the Moon instead of the Earth is the simple fact that the forces involved are much smaller - the Moon's gravity is 1/6th that of Earth's. Instead of exotic nanotubes with extreme tensile strengths, the cable could be built using high-strength commercially available materials, like Kevlar or Spectra. In fact, Pearson has zeroed in on a commercial fibre called M5, which he calculates would only weigh 6,800 kg for a full cable that would support a lifting capacity of 200 kg at the base. This is well within the capabilities of the most powerful rockets supplied by Boeing, Lockheed Martin and Arianespace. One launch is it takes to put an elevator on the Moon. And once the elevator was installed, you could start reinforcing it with additional materials, like glass and boron, which could be manufactured on the Moon