When an extrasolar planet passes in front of its star (transits), its radiuscan be measured from the decrease in starlight and its orbital period from thetime between transits. Multiple planets transiting the same star reveal more:period ratios determine stability and dynamics, mutual gravitationalinteractions reflect planet masses and orbital shapes, and the fraction oftransiting planets observed as multiples has implications for the planarity ofplanetary systems. But few stars have more than one known transiting planet,and none has more than three. Here we report Kepler spacecraft observations ofa single Sun-like star that reveal six transiting planets, five with orbitalperiods between 10 and 47 days plus a sixth one with a longer period. The fiveinner planets are among the smallest whose masses and sizes have both beenmeasured, and these measurements imply substantial envelopes of light gases.The degree of coplanarity and proximity of the planetary orbits imply energydissipation near the end of planet formation.
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