Earth's Twin Update:Reflection of Alien Oceans Could Reveal Habitable Planet

  The next generation of telescopes could reveal the reflection of light or "glint" from Ocean surfaces that signal the existence of Earth-like planets outside our Solar System. Scientists hope the reflection of light from mirror-like ocean surfaces could be picked up by the James Webb Space Telescope, Hubble's successor, set for launch in 2014. Tyler Robinson at the University of Washington in Seattle is hoping this new technique could be used in the quest to find the Holy Grail for exoplanet astronomers - a possible twin Earth.

 "We're focussing on a class of extra-solar planets yet to be detected, so things comparable in size and composition to the Earth and similar distances from their central star as the Earth is from the Sun," Robinson told BBC News. "The goal is to find something Earth-like in almost every sense of the world so we can even prove it has liquid oceans on its surface."