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NASA found “an exoplanet that—as far as we can tell—is a pretty good close cousin to Earth and our sun,” the organization’s John Grunsfeld announced Thursday. “Are we alone in the universe? We’re going to take one small step to answering that question today,” he said. The planet, Kepler 452-B, is in the habitable zone of its star, and is likely to have a mass of five times of that of Earth. The Kepler telescope has defnitively answered that there are solar systems around the stars we see in the night sky, he added.