A closely packed system of low-mass, low-density planets transiting Kepler-11

摘要: When an extrasolar planet passes in front of (transits) its star, radius can be measured from the decrease starlight and orbital period time between transits. Multiple planets transiting same star reveal much more: ratios determine stability dynamics, mutual gravitational interactions reflect masses shapes, fraction observed as multiples has implications for planarity planetary systems. But few stars have more than one known planet, none three. Here we report Kepler spacecraft observations a single Sun-like which call Kepler-11, that six planets, five with periods 10 47 days sixth longer period. The inner are among smallest mass size both been measured, these measurements imply substantial envelopes light gases. degree coplanarity proximity orbits energy dissipation near end formation. NASA's mission, space observatory designed to detect study transit across disk their host hit jackpot discovery six-planet system orbiting now named Kepler-11. Five 47 days, measured. outermost less well characterized thus far. Only other confirmed (Kepler-9, three). This newly discovered resembles our own Solar System being close coplanar, but Kepler-11's orbit closer star. is due continue return data on Kepler-11 some yet, it should provide many valuable constraints models formation evolution solar systems general. (transits), reports days plus