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I was very encouraged to learn that there seems to be some momentum building from the recent 4th Space Elevator Conference.

An impressive group of individuals representing a variety of interests appear ready to come together to create an organization to serve as a coalescing force for those interested in working on the scientific, engineering, economic and policy challenges inherent in constructing the solar system's first space elevator.

While individuals may be pursuing their specific interest in the space elevator, this potential new organization will put forward a united force to disseminate information that is both factual and timely. What's more, by organizing the various challenges ahead this organization will be providing an roadmap of what is being worked on, by whom, what needs to be done etc.

Foreign interest in the space elevator is also growing as was demonstrated at the conference with the strong presence of the Japanese primarily represented by the Japanese Space Elevator Association (JSEA). And in fact JSEA will be holding it's first conference on November 16th and 17th.

Interest in Europe is ongoing with with the 2nd European Space Elevator & CNT Tether Design Conference being held in Luxembourg on December 6th and 7th.

With a new organization in the works several social networking tools will be used to help the organization. There is now a Space Elevator Architect LinkedIn group created, a Twitter channel and I've created a new Facebook group for the organization. This new group, temporarily called the International Space Elevator Facebook group will evolve as the organization is formed and grows. For now I invite you to join this new group.

By Bryan Laubscher

Introduction

There is an old adage: “Getting there isn’t half the fun, it is all the fun!” I want to adapt it to spaceflight: “Getting there isn’t half the effort, it is all of the effort!” The reason for this is the physics of the rocket equation and the depth of Earth’s gravity well. In this missive I will perform a back of the envelope calculation for the cost per kilogram (kg) of transporting mass to the vicinity of Mars. This calculation is rough and certainly not the last word. It does not include the cost of rocket research, development or engineering. Moreover, the overhead of rocket structure, tanks and staging are not included. Thus the rocket equation represents the best case scenario – true rocket performance will be less. However, the resulting cost is stunning and creates a lot of questions around how much exploration, especially manned exploration, can we afford to do with rocket technology!

Note that in this discussion, the vicinity of Mars means that it is not in orbit nor on the surface – those two maneuvers cost more fuel and hence money. I chose the vicinity of Mars because at Mars aerobraking can be used to get into orbit or to the surface without fuel expenditure. Another reason for the choice is that the ΔV, (the amount of velocity change) to reach the vicinity of Mars is less that that required to “soft” land on the surface of the Moon. Thus all costs that I derive are greater for a lunar surface mission

The current controversy over Liftport’s release of a roadmap for the Space Elevator is important because it is allowing for a larger set of issues to be considered. In my opinion, the root of the action by Liftport and the contention to the release of its roadmap point to what is missing in the Space Elevator community.

Because we are in the “infancy” of the Space Elevator, it is not clear what it will grow into in its maturity. Therefore, we have a broad range of work that is valid, ranging from speculative visions to detailed scientific and engineering research. Unfortunately, not all of it is of high quality nor does all of it further the Space Elevator. In short, we have exuberant individuals and small teams working independently and in concert, some for the positive and some for the negative! There has been no oversight, criticism or acclimation of effort, no matter how well carried out or how shabbily executed. This must change!

As a community we need to work more closely together to encourage and support good work while discouraging shoddy work. And we need to do this out of the public eye. All of us need to be willing to have our work reviewed. Indeed, my most talented scientific colleagues insist on having their work reviewed by peers because they know the importance of their work and they honor their reputations! This level of activity is for adults with serious intentions. It is not for the insincere or insecure. Through this process we will all be called to a higher standard of work.

Liftport logo

A few days ago Liftport released a document titled “Road Map to the LiftPort Space Elevator”. The document is written to be a plan to develop the space elevator. It is a good idea to assemble the components for the space elevator that have been developed into a publicly available roadmap. This will help people understand and get involved in the effort. Unfortunately, the Liftport roadmap has little relevance to the space elevator development effort as a whole. Liftport apparently has not read or understood the literature on the space elevator and had no input from technical experts on the space elevator or large space or civil projects.

The team that compiled this roadmap consisted of: Michael Laine who has no technical background, Tom Nugent is a recent graduate with limited experience on the space elevator, and two student interns at Liftport. The three people they list as having supplied helpful input have extremely limited involvement in the space elevator development and have their own competing concepts. A video posted on the web shows Michael Laine, one of the authors of the document, giving a talk on the elevator (my old video playing the background) where he states he doesn’t know how the components work so don’t embarrass him by asking.

The major pitfalls of this roadmap include but are not limited to:

At the end of August an announcement came out from Los Alamos National Laboratory stating they had produced material 100 times stronger than steel (pound for pound). This is about 50GPa or about 15 times Kevlar, Vectran or Spectran. Efforts to produce large commercial quantities of material with these characteristics are underway. Liftport has this material strength milestone at the year 2020 and this drives much of their roadmap.