I’ve been attending the 2008 Space Elevator Conference being held at Microsoft’s Redmond campus this weekend. The many talks and papers given there clearly demonstrate the tremendous dedication and creative engineering that can be found in this nascent field.
For those of you who are fuzzy on the concept, the general idea of the space elevator involves running a tether from the surface of the earth to geosynchronous orbit and beyond. A mechanical “climber” then ascends and descends the tether, delivering payloads into orbit. If this sounds like science fiction, that’s because until recently, it was. Independently conceived by a Russian (Artsutanov) and an American (Pearson), the space elevator concept was popularized by the late science fiction writer Arthur C. Clarke in his 1979 novel, “The Fountains of Paradise”. At that time, no material was light enough and strong enough to make it possible. But with the developing field of nanotechnology and the discovery of carbon nanotubes (CNTs), a number of people have begun to take the idea more seriously. (For the record, Clarke is also credited with originating the idea of using geosynchronous satellites as telecommunications relays back in 1945, a concept that completely revolutionized communications.)
Now while the general concepts behind the space elevator are simple, the implementation is anything but. There are numerous technical issues to be worked out and an enormous initial investment to be made. But the potential payoff is huge. Currently, payloads to geosynchronous orbit constitute only about 3.5% of total launch weight and cost on the order of $5-10,000 per pound of payload. Payload efficiency on the space elevator could be as much as 90% or more depending on the method used. Payload envelopes wouldn’t be limited to the size and shape of cylindrical payload bays and nose cones. Pollution from rockets would be eliminated. Most importantly though, the cost per pound would plummet. As a result, a new space era would be born.
Why is this important? New materials and manufacturing methods could be developed which can only be achieved in zero-gravity. Off-world mining would allow us to supplement our diminishing resources. Solar power beamed from space could meet the needs of our increasingly energy-hungry world. Whether the space elevator is built by one country or becomes a multi-national effort, it will be a huge stimulus for the world economy, particularly for the key players involved.
But it’s not going to happen without support and financial commitment. True, NASA currently offers as much as four million dollars in prizes for the Spaceward Games, a competition designed to stimulate progress in the field. But the planning, the engineering analyses, the proof-of-concept work is all being done on a shoestring as thin as the carbon nanotubes themselves. Uncounted hours are being volunteered by engineers and enthusiasts the world over, people who know this will one day become a reality. But such dedication can take the space elevator only so far. The day is quickly coming when we’ll have to make a greater commitment if we want to participate in what will surely be one of the greatest engineering feats humankind has ever seen.