Exploring the Possibility of Life Around Saturn
Reports that there may be large amounts of water in liquid form just under the surface of Enceladus, a moon of Saturn, has brought the satellite to the attention of scientists in the field of astrobiology – the study of life on worlds other than Earth.
According to a NASA press release, "the presence of liquid water inside Enceladus would have major implications for future astrobiological studies on the possibility of life within icy bodies of the outer solar system." Scientists theorize that the presence of water, plus the presence of organic compounds, may result in the evolution of simple life forms.
Such a theory, of course, has yet to be tested. Unlike their colleagues in other branches of biology, astrobiologists do not yet have bacteria, plants or animals to study. Instead, they are left to theorize about the possibility of life on other planets and moons.
Despite the hostility of most real estate in the Solar System, astrobiologists have raised the issue of life in a number of widely differing environments.
While Enceladus has shot to near the top of the list of potential life zones, Mars holds the title of long-time astrobiology favorite. Space probes have never conclusively proven that life exists or has existed on Mars, but have not entirely disproven it either. Confusing readings from an experiment on a Viking lander, coupled with possible fossilized bacteria found in a meteorite that may have originated from Mars, have left open the question that some sort of organism might exist on the Red Planet.
Also high on the list of potential homes to extraterrestrial life is Europa, a moon of Jupiter. Like Enceladus, Europa may have a large sea of liquid water just under the surface.