No abstract

We are now developing an innovative SETI project, tentatively named seti@home, involving massively parallel computation on desktop computers scattered around the world. The public will be uniquely involved in a real scientific project. Individuals will download a Screensaver program that will not only provide the usual attractive graphics when their computer is idle, but will also perform sophisticated analysis of SETI data using the host computer. The data are tapped off Project Serendip IV’s receiver and SETI survey operating on the 305-meter diameter Arecibo radio telescope. We make a continuous tape-recording of a 2 MHz bandwidth signal centered on the 21 cm H I line. The data on these tapes are then preliminarily screened and parceled out by a server that supplies small chunks of data (50 sec of 20 kHz bandwidth, a total of 0.25 MB) over the Internet to clients possessing the screen-saver software. After the client computer has automatically analyzed a complete chunk of data (in a much more detailed manner than Serendip normally does) a report on the best candidate signals is sent back to the server, whereupon a new chunk of data is sent out. If 50,000-100,000 customers can be achieved, the computing power will be equivalent to a substantial fraction of a typical supercomputer, and seti@home will cover a comparable volume of parameter space to that of Serendip IV.

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We explore how questions related to developing a sustainable human civilization can be cast in terms of astrobiology. In particular we show how ongoing astrobiological studies of the coupled relationship between life, planets and their co--evolution can inform new perspectives and direct new studies in sustainability science. Using the Drake Equation as a vehicle to explore the gamut of astrobiology, we focus on its most import factor for sustainability: the mean lifetime of an ensemble of Species with Energy--Intensive Technology (SWEIT). We then cast the problem into the language of dynamical system theory and introduce the concept of a trajectory bundle for SWEIT evolution and discuss how astrobiological results usefully inform the creation of dynamical equations, their constraints and initial conditions. Three specific examples of how astrobiological considerations can be folded into discussions of sustainability are discussed: (1) concepts of planetary habitability, (2) mass extinctions and their possible relation to the current, so-called Anthropocene epoch, and (3) today's changes in atmospheric chemisty (and the climate change it entails) in the context of pervious epochs of biosphere--driven atmospheric and climate alteration (i.e. the Great Oxidation Event).