EARTH-LIKE WORLDS COME INTO VIEW

摘要

In the race to find planets around other stars, the grand prize would be to find a world like Earth orbiting a star like the sun-and astronomers closed in on that trophy in 2009. The first known exoplanets were huge and gassy. Then in February a European group led by Alain Leger of the Institut d'Astrophysique Spatiale in Paris and Daniel Rouan of the Paris Observatory used the Corot space observatory to find a planet less than twice the diameter of Earth, the smallest confirmed exoplanet ever seen.