Astronomers have confirmed the existence of a new class of planet: a waterworld with a thick, steamy atmosphere. The exoplanet GJ 1214b is a so-called "Super Earth" - bigger than our planet, but smaller than gas giants such as Jupiter. Observations using the Hubble telescope now seem to confirm that a large fraction of its mass is water. The planet's high temperatures suggest exotic materials might exist there. "GJ 1214b is like no planet we know of," said lead author Zachory Berta, from the Harvard Smithsonian Center for Astrophysics.

Emergency teams have found two more bodies in the partially submerged Costa Concordia cruise liner that sank off the western coast of Italy. It brings to five those known to have died after the ship, carrying more than 4,000 people, hit rocks on Friday. The coastguard said divers had found the bodies of two unidentified elderly men trapped in a flooded area. Earlier three survivors were found, more than 24 hours after the ship ran aground near a Tuscan island.