Another place which is wildely believed to be able to contain life, is Jupiter's moon, Europa. Observation show that Europa's surface is made of thick ice. Many scientists believe that under this layer of ice that covers the entire planet, there are vast oceans of liquid water. Water -- as we all know -- is one of the basic foundation for the existence of life.
Since the ice layer on Europa's surface is too thick to permit sunlight to go through, it is obvious that any life that might exist on this moon will not be able to draw its energy from sunlight. Although this might initially seem as a problem that prevents from life to exist on Europa, it is actually not.
Recent observasion on our own planet Earth has revealed that life exists in the deepest points of our oceans, where sunlight does not reach. Instead of drawing energy from sunlight, these deep-ocean creatures obsorb energy from the immense heat of the earths magma.
Since it is highly possible that the same conditions also exist in the deep points of the oceans of Europa, it is not unlikely that life has also spawned there. However, the human race still doesn't posses the ability to explore the oceans of Europa. this is why this hypothesis will stay unanswered for a few more years to come.