Abstract
One of the great surprises of the late 20th century was the discovery
 that a saltwater sea lies beneath an icy surface crust that covers
 Jupiter�fs moon Europa. Saturn�fs moon Enceladus has also been
 discovered to have an icy surface beneath which an ocean of liquid
 water provides the source of jetting plumes of water ice at the moon�fs
 south pole. Jupiter�fs Europa, Callisto, and Ganymede, Saturn�fs
 Enceladus and Titan, and possibly Neptune�fs Triton are all worlds
 in the outer solar system that are now known to harbor reservoirs of
 H20 in solid and liquid form. Inasmuch as life is found wherever 
there is water on Earth, the search for life at these destinations 
has become compelling. Any life detected at the remote �gocean worlds�h
 in the Outer Solar System is likely to have formed and evolved along 
an independent path from life on Earth itself.
The search for water and life in the Universe does not end with our 
solar system. In just the past decade the existence of scores of planets 
around nearby stars has been confirmed indicating that there are more
 planets then stars in our galaxy. It is expected that a class of
 these planets are ocean worlds. Humanity has surely embarked upon one of
 the most stirring epochs of exploration in history.