On my flight to Paris last night, I finished a detailed reading of The Space Elevator by Bradley Edwards and Eric Westling (I praised the book in an earlier post based on skimming it and reading a few sections). This 2003 book is a real tour de force that describes and analyzes the coming technology of space elevators with great clarity and detail. The amazing thing is that the space elevator (SE) is now not so much a problem of waiting for scientific breakthroughs as it is solving a lot of challenging but not unprecedented engineering problems (and getting the funding). The main technical breakthrough took place in 1991, with the discovery of carbon nanotubes (CNT). This material has many useful properties and a growing list of applications, but for SE applications, its main strength is its... strength! It's incredibly strong and light.
Within the last few months, I read of a technical breakthrough in the rapid fabrication of CNT ribbons and sheets of the type needed by the SE at a prototype rate of 7 meters per minute (published in Science magazine, August 19). These prototypes are very strong but not yet strong enough, and this is not fast enough for the thousands of kilometers of CNT ribbon that will be needed for the SE -- but it's a huge advance over previous methods of making CNT composites.
I also learned about the LiftPort Group a few weeks back -- a commercial venture that is developing SE technology now. They have begun to test early versions of the robotic "climbers" that will pull themselves up the ribbons and eventually to space. Their small test lifters recently climbed 1000 feet (305 meters) up a balloon-suspended test ribbon.
Here's the thing. Rockets are cool and have gotten us where we are today in space, but chemical rockets can never be an efficient and cost-effective way to get large cargos and people to space on a routine basis. The Earth's gravity well is just too deep, and a huge fraction of any rocket has to be fuel. The space elevator is the solution. It will eventually make access to low Earth orbit and beyond as routine and cost-effective as international airline flight is today. The astounding thing is that "eventually" is not centuries or even decades. We could have these things in 10-15 years. The benefits will be enormous. This is not science fiction, boys and girls.