"These planets are unlike anything in our solar system. They have endless oceans." Astronomers have found planets covered by global ocean with no land in sight - http://news.harvard.edu/gazette...
"Astronomers have found a planetary system orbiting the star Kepler-62. This five-planet system has two worlds in the habitable zone — the distance from their star at which they receive enough light and warmth for liquid water to theoretically exist on their surfaces. (...) Kepler-62e is 60 percent larger than Earth, while Kepler-62f is about 40 percent larger, making both of them “super-Earths.” They are too small for their masses to be measured, but astronomers expect them to be composed of rock and water, without a significant gaseous envelope. As the warmer of the two worlds, Kepler-62e would have a bit more clouds than Earth, according to computer models. More distant Kepler-62f would need the greenhouse effect from plenty of carbon dioxide to warm it enough to host an ocean. Otherwise, it might become an ice-covered snowball. “Kepler-62e probably has a very cloudy sky and is warm and humid all the way to the polar regions. Kepler-62f would be cooler, but still potentially life-friendly,” said Harvard astronomer and co-author Dimitar Sasselov." - Amira
See also "The Songs of Distant Earth" - Arthur C. Clarke's science fiction novel which takes place almost entirely on the faraway oceanic planet of Thalassa. :-) http://en.wikipedia.org/wiki... - Amira
Thank you, @Amira!! :) - Harold Cabezas