Other Life in Our Solar System?

[sfscriv]

Seth Shostak is a senior astronomer at the SETI Institute in Mountain View, California

Saturn's moon Enceladus - geysers of frozen water spewing from cracks in Enceladus' southern hemisphere. Scientists think reservoirs of liquid water lie beneath the frozen surface and are warmed by gravitational interactions between Enceladus and other moons around Saturn.

Mars - Likely to be salty meltwater only inches beneath Mars' dusty surface with the chance of protoplasm.

Saturn's moon Titan - The only world in the solar system (besides Earth) known to sport liquid lakes. These are lakes of ethane and methane — liquid natural gas — endlessly topped up by hydrocarbon rain. Despite the odd ingredients and Titan's gelid temperatures (minus 290 Fahrenheit, or minus 179 Celsius), it is a world where chemistry's a happening enterprise.

Jupiter's moon Europa - since there's probably more liquid water there than in all of Earth's oceans. The downside is that Europa's vast, salty seas lie beneath roughly 10 miles of ice. It would be difficult to get a probe beneath this icy armor. Europa's oceans are darker than a cave — which means photosynthesis won't work. However, something down there may subsist on geothermal heat or complex molecules from the surface.

Venus - It has scorching surface temperatures (850 F, or 454 C). The planet is generally assumed to be as sterile, but high in the Venusian atmosphere temperatures are refreshingly tolerable. Atmospheric sulfur dioxide and carbon monoxide might serve as food for floating microbes.

Jupiter's moons Callisto & Ganymede - May have buried, liquid oceans beneath at least 60 miles (100 km) of rock.

[PhoenixKsE]

My theory has always been that at some point, long ago, the sun was bigger or hotter than it is now, and Mars was the perfect distance away to support life. This could also be true of other planets/moons that seem to have water. Or, on the other hand, maybe it is set up that way because at some point, long in the future, the sun will get bigger or hotter, and Mars (and later, those other planets/moons) will become inhabitable once the ice melts.