How can such a cold moon support life?
Many scientists believe that Europa’s vast subterranean sea could host living microorganisms similar in size and complexity to bacteria found on Earth. Others question whether a frozen moon with a surface temperature of -170 C can produce sources of energy useful for the basic chemical reactions necessary for life. But a new report in the January 27th 2000 issue of the journal Nature concludes that Europa does indeed contain plenty of biological fuels, thanks to billions of charged particles that constantly rain down from neighboring Jupiter. This relentless bombarbment of radiation “should produce organic and oxidant molecules sufficient to fuel a substantial Europan biosphere,” writes Christopher Chyba, associate professor (research) of geological and environmental sciences at Stanford University. On Earth, all organisms use carbon as a basic building block of life to construct everything from cells to DNA. Many organisms obtain their energy from carbon-based molecules like sugar, an
