Scientists have found one.
So reports Ian Musgrave at Panda’s Thumb. The planet orbits a star in the Gliese 581 system:
“Importantly, the orbit for Gliese 581d has been refined too. It is now definitely within the habitable zone of its star. Gliese 581d is likely very unlike Earth, and it and Gliese 581c are probably water worlds. The refinement of the orbit of 581d means it is very-likely covered in liquid water, when the planet was first described it seemed more likely it would be an ice world . . .”
How strange it would be to travel to another star and discover a world covered in water. And how many of them must be out there—as many as the sands of the shore. How at once strange and familiar that would be to see one of them, almost like Charlton Heston in Planet of the Apes, after travelling in a space ship for a long period of time, suddenly, and with startled recognition, discovering that he had never really gone anywhere, and saying: “I’m home.”