Who is CASI? CASI is a DNA computer that predicts how long humans can survive under the sealed domes of Biosphere 2. CASI's creator, Tess Eliot needs that data for a more pressing prediction--what the soups of pollution we're stirring is doing to Biosphere 1, Planet Earth. Her space scientist husband, Chris Elkay thinks she's pursuing an impossibly complicated problem, even for a Climate Analog Situation Indicator. But he has his own impossible problem--why...