Whether they are advocates of space exploration or not, I believe that most human beings at one time or another look toward the sky and wonder if there is "anyone out there." For those of us who believe we are not alone in the universe, it's truly an easy assumption to think that among all those stars are other worlds like Earth.rnThis is why I'm thrilled that NASA is embarking on a new mission to specifically scan a region of our galaxy for Earth-like planets orbiting, as the agency has described, "in the habitable zone of stars like our Sun." The key, of course, is that the planet must be close enough-but not too close-to the star for habitable temperatures and liquid water, essential for life, to exist.
展开▼
