Consider a mission to place a weather satellite in a Sun-synchronous orbit around an oblate Earth (J = 1082.6 10-6). The orbit perigee is located at the equator, and its radius, rp = 7000 km, is selected to be just high enough to ensure that the Earth's upper atmosphere does not induce measurable drag. Find the apogee radius needed to be to keep perigee and apogee at the equator throughout the operational life of the satellite.