On Day One Neal Stephenson and his team from Arizona State University presented on an awe-inspiring structure. I’m not sure I’d endorse it as a structure for space-launch, at least not yet, but a 20 km high Tower has a certain gravitas that makes it worthwhile contemplating. Certainly the exercise of designing a mega-structure (even a baby mega-structure like this Tower) will develop computational tools and experience that will help future mega-structure design, some of which will help develop and terraform the Moon, Mars and Beyond.
The mass figures were rather surprising, while the structural material choice was logical, as steel is the most abundant material we make after concrete. One estimate, before it was trimmed back, was about 2 billion tonnes. I sat next to Patti Smith, one of the chief Regulators of Commercial spaceflight, and exchanged comments with her – mostly positive, though my memory is patchy. I quickly estimated that 2 billion tonnes of steel was about 30 years of global production, but my global production figures are probably about 10 years out of date. I have a soft-spot for Colossal Mega-Structures. The automation/teleoperated machinery that building such would require could easily extrapolate to use in space, where multi-kilometre wide structures are regularly discussed. The technological spin-offs of a Space Tower would be profound – but unknowable if we never try to build it, even in detailed virtuality.