A spherical satellite circling the sun is to be maintained at a temperature of 25?C. The satellite rotates continuously and is covered partly with solar cells having a gray surface with an absorptivity of 0.1. The rest of the sphere is to be covered by a special coating which has an absorptivity of 0.8 for solar radiation and an emissivity of 0.2 for the emitted radiation. Estimate the portion of the surface of the sphere which can be covered by solar cells. The solar irradiation may be assumed to be 1,420 W/m2 of surface perpendicular to the rays of the sun.GIVENA spherical satellite partially covered with solar cells is orbiting the sunSatellite temperature (Ts) = 25?C = 298 KSolar cell absorptivity (αc) = 0.1Absorptivity of the rest of the satellite (α2s) = 0.8Emissivity of the rest of the satellite (εs) = 0.2ASSUMPTIONSAmbient temperature (T??) = 0 KQuasi steady stateSolar irradiation (Iso1) = 1420 W/m2 of the surface perpendicular to the rays of the sunSatellite and cell surfaces are graySurface temperature of the satellite isuniform

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T= 298 K 4= 0.8 T.- OK lae= 1420 Wim2 Solar Cells 4 =0.1