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Hello, Universe? Anyone Home? WASHINGTON, D.C. (Achieve3000, November 3, 2010) For thousands of years, people have asked the timeless question: Are we alone in the universe? Now, scientists are inching closer to an answer. For the first time, scientists say they have spotted an Earth-like planet that fits into what is sometimes called a "Goldilocks zone": a region of space that's not too hot and not too cold. It's juuuust right to support life. The new exoplanet is named Gliese 581g. It was discovered by astronomers R. Paul Butler of the Carnegie Institution of Washington and Steven Vogt of the University of California at Santa Cruz. Butler and Vogt found the planet circling a dwarf star called Gliese 581, which is about one-third the strength of our sun. Using ground-based telescopes, the two scientists tracked the star's precise movements over 11 years and watched for wobbles that indicate planets are circling it. Gliese 581g is located about 120 trillion miles away from Earth, so we won't be taking a close look anytime soon. Still, in the scheme of the vast universe, said Vogt, "the planet is "right in our face, right next door to us." In fact, if you were standing on Gliese 581g, you could easily see our solar system's sun. So far, astronomers have learned that the new planet is about three times the mass of Earth and is slightly larger in width. Gliese 581g is also much closer to its sun than Earth is to ours. The exoplanet is about 14 million miles from its sun. It completes a full orbit in only 37 days. Earth, on the other hand, is 93 million miles away from our sun and completes a full orbit in 365 days. Based on Gliese 581g's location from its sun—it's not too far away nor too close— scientists suspect that it could contain liquid water. This leads some astronomers to suggest that it might also support life. This doesn't mean Gliese 581g is home to E.T.like creatures, or even humans and animals. However, even a simple single-cell bacteria or the equivalent of shower mold would shake perceptions about the uniqueness of life on Earth. Previously, astronomers have proclaimed that planets outside our solar system were habitable, only to have them turn out not to be conducive to life. But Gliese 581g is unlike any of the nearly 500 exoplanets astronomers have found outside our solar system. This is due to its location inside a Goldilocks zone, or "habitable zone," of space. Not only is Gliese 581g not too hot and not too cold to support life, but it is neither too big nor too small for suitable surface, gravity, and atmosphere conditions. This makes it a promising candidate for habitability. "This really is the first Goldilocks planet," said Butler. For now, it's unclear whether water actually exists on Gliese 581g, or if the planet is actually habitable. Astronomers have determined that temperatures on Gliese 581g can reach a fiery 160 degrees Fahrenheit or an icy 25 degrees below zero. And because the planet doesn't rotate much, one side of the planet is almost always bright, while the other is dark. Still, on some parts of the planet, Vogt said, it would be "shirt-sleeve weather." The recent discovery of Gliese 581g hints to scientists that planets like Earth are probably not that rare. Butler and Vogt estimate that there are 200 billion stars in the universe. According to their calculations, as many as 1 out of 5 to 10 stars could have planets that are Earth-sized and located in the habitable zone. That would mean 40 billion planets would have the potential for life. Some astronomers, however, caution that this figure is too speculative to prove. Although Gliese 581g's ability to sustain life is currently open to speculation, scientists will have ample time to continue their research. Astronomers predict the planet's sun will live on for billions of years, much longer than our own sun. According to Butler and Vogt, that just increases the likelihood of life developing on the planet. "It's pretty hard to stop life once you give it the right conditions," Vogt said. The Associated Press contributed to this story.