One Third of Known Planets May Be Enormous Ocean Worlds

A new model of Super-Earths implies many of these planets are covered in enormous, thick oceans. (Credit: NASA) Water is a key ingredient for life — and new research suggests we might find it all over the galaxy. Scientists looked at the mass of Super-Earths, a kind of planet common across the cosmos but not present in our own solar system. These rocky worlds are several times larger than Earth, but the team's analysis of known Super-Earths reveals something astounding: Many of them may be literal water worlds. According to the research, many of these planets may be half water. By comparison, water is just a tiny fraction of Earth's mass. But that doesn't mean these Super-Earths are friendly places to live. The Harvard-led team determined that those planets with 1.5 times Earth’s radius or below would be terrestrial, or rocky. Super-Earths above 2.5 Earth radius might more like tiny ...