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Exoplanet orbiting red giant gives hints of Earth's future

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Astronomers have discovered a new planet in another solar system orbiting a red giant star that provides clues into what may happen to our own solar system five billion years from now when our own, younger sun becomes a gigantic old star

The exoplanet (a planet in another solar system) is about six times the mass of Jupiter and orbits about 40 percent closer to its star, dubbed HD 102272, than Earth does around the sun. Scientists say this is apparently the shortest distance that a planet can be from a red giant (a large, relatively cool, elderly star) without burning up.

Astronomers from Pennsylvania State University in State College and Nicolaus Copernicus University in Poland found the exoplanet using the Hobby-Eberly Telescope at McDonald Observatory in the Davis Mountains of West Texas. They observed the red giant wobbling from the gravitational pull of a nearby object, identified as the exoplanet. They suspect there may also be a second planet orbiting the red giant, which would be a first. The findings are set to be published in the Astrophysical Journal.

Earth is expected to be destroyed by the sun when it becomes a red giant in about five billion years, but astronomers suggest that the effects on other planets may be far more pleasant. Instead of being engulfed by the massive star, frozen worlds–if far enough from the sun–such as Jupiter's moon Europa might actually warm up enough to sustain life, Penn State astrophysicist Alexander Wolszczan told SPACE.com.

(Artist's rendering of a red giant destroying a nearby planet courtesy of NASA.)