12227"Super-Earths are Likely to Have Oceans and Continents"
- Jan 9, 2014URL to an interesting post from the Daily GalaxyChrisFirst few paragraphs"
"Are the surfaces of super-Earths totally dry or covered in water?" said Nicolas B. Cowan, a Northwestern University astrophysicist at the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) . "We tackled this question by applying known geophysics to astronomy." Massive terrestrial planets, called "super-Earths," are known to be common in our galaxy, the Milky Way. Now Cowen and a University of Chicago geophysicist report the odds of these planets having an Earth-like climate are much greater than previously thought.Cowan and Dorian Abbot's new model challenges the conventional wisdom which says super-Earths actually would be very unlike Earth -- each would be a waterworld, with its surface completely covered in water. They conclude that most tectonically active super-Earths -- regardless of mass -- store most of their water in the mantle and will have both oceans and exposed continents, enabling a stable climate such as Earth's.
"Super-Earths are expected to have deep oceans that will overflow their basins and inundate the entire surface, but we show this logic to be flawed," he said. "Terrestrial planets have significant amounts of water in their interior. Super-Earths are likely to have shallow oceans to go along with their shallow ocean basins."
In their model, Cowan and Abbot treated the intriguing exoplanets like Earth, which has quite a bit of water in its mantle, the rocky part that makes up most of the volume and mass of the planet. The rock of the mantle contains tiny amounts of water, which quickly adds up because the mantle is so large. And a deep water cycle moves water between oceans and the mantle. (An exoplanet, or extrasolar planet, is a planet outside our solar system.)"