Project at Arizona State 20km Tower http://hieroglyph.asu.edu/project/the-tall-tower/ The tower project began when Neal Stephenson started asking a simple question: how tall can we build something? As he started working with structural engineer Keith Hjelmstad, it turned out that this question has some surprising answers. To learn more about the project or get involved, check out the Tower Group. http://hieroglyph.asu.edu/?gpages=tower-project High Altitude Launch for a Practical SSTO Existing engineering materials allow the constuction of towers to heights of many kilometers. Orbital launch from a high altitude has significant advantages over sea level launch due to the reduced atmospheric pressure, resulting in lower atmospheric drag on the vehicle and allowing higher rocket engine performance. High altitude launch sites are particularly advantageous for single stage to orbit (SSTO) vehicles, where the payload is typically 2% of the initial launch mass. An earlier paper enumerated some of the advantages of high altitude launch of SSTO vehicles. In this paper, we calculate launch trajectories for a candidate SSTO vehicle, and calculate the advantage of launch at launch altitudes 5 to 25 kilometer altitudes above sea level. The performance increase can be directly translated into increased payload capability to orbit, ranging from 5 to 20% increase in the mass to orbit. For a candidate vehicle with an initial payload fraction of 2% of gross lift off weigh t, this corresponds to 31% increase in payload (for 5 km launch altitude) to 122% additional payload (for 25 km launch altitude). http://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.1541305 Mass of Extremely Tall Truss Towers http://alnaspaceprogram.org/towers.html http://alnaspaceprogram.org/studies/towers/mass_of_extreme_towers.html http://www.newscientist.com/blogs/culturelab/2012/09/making-science-fiction-... Space tower: could we build a stratosphere scraper? 15:39 10 September 2012 Jim Giles, consultant Could a fictional tower that reaches far into the stratosphere really get built? The new Center for Science and the Imagination at Arizona State University brings novelists and engineers together to push the boundaries of science NEAL STEPHENSON has a big idea. He imagines a 20-kilometre-high steel tower that reaches into the stratosphere. From that height, weather patterns would be distant swirls. Planes could save fuel by docking at the tower rather than landing, and space missions could do the same by launching from it. A science-fiction novelist, Stephenson is not just using his idea as the basis for a story. The author of the critically acclaimed Snow Crash is taking the unusual step of teaming up with a structural engineer, Keith Hjelmstad at Arizona State University (ASU) in Phoenix, to work out how to actually build the tower. The project is not a one-off. This month will see the launch of the Center for Science and the Imagination, an ASU project that will bring together scientists, engineers, artists and writers and encourage them to think big. The idea is to team artists and authors with ASU researchers to turn science fiction into reality. In the first half of the 20th century, pulp science fiction, with its focus on intergalactic exploration, helped inspire a generation of children who grew up wanting to be astronauts and rocket engineers. By contrast, contemporary sci-fi is often far more dystopian. This project aims to find that inspiration again, not only for future scientists, but also for those who already have the skills to carry out such projects. "A well-written sci-fi story can obviate a lot of PowerPoint presentations and meetings," says Stephenson. Hjelmstad is now analysing the feasibility of Stephenson's tower. Preliminary modelling suggests that it could support its own weight, but many questions remain. Hjelmstad must determine, for instance, whether the tower can support the payload associated with each of the uses that Stephenson imagines. "The tower pushes well beyond anything anyone has ever done in structural engineering," says Hjelmstad. "Building [it] would be the biggest project ever undertaken by humans." The tower story will be published by Hieroglyph, a joint project between the centre and Stephenson, which will host online forums for further discussion. Other writers can also use Hieroglyph to contribute new stories and collaborate with ASU scientists. Author Cory Doctorow, for example, has a story and accompanying research project based around the idea of sending 3D printers to the moon, where the devices would build a base for humans to inhabit later. The idea of focusing on tangible outcomes, albeit ones that will probably not be realised for a decade or more, has not been a major part of previous collaborations between artists and scientists. "It has been a one-way door a lot of the time," says Tami Spector, a chemist at the University of San Francisco who writes about sci-art. "Scientists tend to view art as in service of science and artists tend to view science as a tool for doing art." The Wellcome Trust, a London-based biomedical research funder, spent close to £3 million on art-science collaborations between 1996 and 2006. When independent reviewers examined the programme in 2009, they praised the art it produced but also noted that it had little impact on scientific practice. Things may now be changing. In one recent project, for example, fashion designer Helen Storey teamed up with chemist Tony Ryan to treat clothes with compounds that purify the air. The pair are now developing a product for home use. The Wellcome Trust's arts adviser Meroë Candy sees a wealth of such possibilities. She says artists can help scientists visualise data to reveal previously unseen patterns or ask questions that lead research in unexpected directions. If Candy is right, the ASU centre may mark a new attitude towards sci-art collaboration. For Ed Finn, who will direct the centre, success will be measured in part by a change in thinking about "audacious moonshot ideas" that are seen as too ambitious for the incremental process of contemporary science. "I'll know we have succeeded if in five years we have lots of scientists and engineers clamouring to get involved in our seminars," he says.