And if life on Mars proves a bust, try Europa. The Mars Global Surveyor shot, shows gullies perhaps formed by water. But, he adds, the science of astrobiology is advancing - driven by an increasing appreciation of the diversity of habitats on Earth. Wherever conditions are appropriate, life can make it, potentially. Water either is split to condense molecules or is introduced to break down molecules.
Life is in the business of capturing energy and transferring that energy into chemistry.
For a walk on the wild side, he suggests microorganisms associated with deep-sea hydrothermal vents, found along ridges where magma wells up from Earth's mantle to form new crust. Many organisms can breathe oxygen from seawater and eat hydrogen sulfide. Others eat hydrogen and breathe carbon dioxide. Now shift to Mars. While the planet has no plate tectonics, Pace says, there is water in the rock and soil that overlays Martian bedrock.