The eclipsing binary Kepler-47 is the first system detected to have multiple  circumbinary planets (Orosz et al. 2012). The binary consists of a Sun-like star and a companion roughly one-third its size, orbiting each other every 7.45 days. The planets were detected using transit photometry when each planet transits the stars of the binary. Figure 1 shows some of the planetary transits of this system. The inner and outer planets of Kepler-47 system have radii 3.0 and 4.6 times that of Earth, respectively. The inner planet, Kepler-47b, has an orbital period of 49.5 days. The outer planet’s orbital period is 303.2 days.

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