Water Planets
"CfA astronomer Dimitar Sasselov, together with two of his colleagues,
have begun the pioneering task of modeling the interiors of
super-earths. They address in particular the class of objects rich in
water. They define a "water planet" as any super-earth whose mass is
more than 10% water, whose core is made of silicates or metals, and
whose surface layer is lacking in significant amounts of gas. They model
nine possible water planets with a range of masses and water contents
(up to 50%), and study the near-surface layer for icy or ocean-like
properties. "
http://www.physorg.com/news183389336.html