Sunday, December 03, 2006

Getting up there - Space elevators

Over the past few years this exciting concept has been steadily moving towards reality. When it does happen - and I believe it will - it will be a milestone in man's development.

Basically it involves putting a very large satellite or asteroid into geostationary orbit (so it appears fixed over one place on Earth like many satellites) and dropping a cable down to earth. This cable is then used by elevators to haul material and possible people up to orbit - slowly, safely and very cheaply. Like a railroad to the heavens...

The technology does not quite exist yet especially a cable strong enough but many feel the challenges can be over come. Research is being done and companies have been set up to build elevators. There is now an prize and annual competition to test the technology for short cables.

It would also seem to be energy efficient and friendly to the environment - the elevators might even be solar powered from collectors on the satellite.

Links
Wikipedia article

National Space Society Special Interest Chapter for the Space Elevator

3 comments:

Brian Dunbar said...

It would also seem to be energy efficient and friendly to the environment - the elevators might even be solar powered from collectors on the satellite.


Maybe - but not for a while.

One problem is that even after we get the cost _down_ to get to orbit it is still going to be expensive for a few years to operate anything in space. Score a point for a ground-based system to supply power.

Another problem is that the system must direct a free-electron laser to the lifter. People might be wary of a constellation of satellites firing (harmles) beams down.

brian dunbar
liftport

Andrew Mancey said...

Good point. But there seem to be so many possible solutions to powering the lifters that I am sure some good ones will be found... may take while as you say.

Andrew Mancey said...

Some further thoughts...

Climber with rotatable collector so it could initially use power beamed (or reflected sunlight) from the ground.

Further up the collectors could be repositioned to collect power from the satellite(s). If lasers are used the frequency could be chosen so that it would be absorbed or sufficiently attenuated by the lower atmosphere so that there no danger to us folks on the ground.

Large scale power generation in orbit will be needed in future elevator or not. The satellite will be in sunlight for much more of the day than the ground station and not subject to unpredictable weather. Energy storage is possible on the satellite since weight is not a problem. Even deserts get cloud sometimes.

The collection system could double as a solar power system for emergencies in case of beam failure.