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　　New Planet System FoundMay Have Hidden Super Earth

　　An artists impression of two Saturn-like planets orbiting the star Kepler-9.

　　Image courtesy NASA

　　Rachel Kaufman

　　for National Geographic News

　　Published August 26, 2010

　　A newly discovered planetary system orbiting a sunlike star may conceal a rare super-Earth, according to data from NASAs Kepler space telescope.

　　Launched last March, Kepler was designed to look for extrasolar planets, aka exoplanets, via transitsthe periodic dimming of light from stars due to planets passing in front them, as seen from the telescopes vantage point.

　　After analyzing seven months worth of data from Kepler, a team led by Matt Holman of the Harvard-Smithsonian Center for Astrophysics found two transiting exoplanets orbiting the star Kepler-9, which lies about 2,300 light-years from Earth.

　　One of the planets, dubbed Kepler-9b, takes just over 19 days to orbit its star. The other, Kepler-9c, takes almost 39 days to complete an orbit.

　　The researchers noticed that both planets orbital periods speed up and slow down at regular intervals. This means the two planets are locked in gravitational resonanceso that each planets gravity is affecting the others orbit.