The Parker solar probe, orbiting the Sun, experiences solar radiation flux of 650 kW m ⁻² . The heat shield (area =1.0 ~m ^2 , emissivity =1.0 ) surrounding the probe is internally cooled by a conductive heat transfer mechanism. The shield is designed to operate at 1500 K . The required heat transfer rate (in kW ) to be delivered by the cooling system is approximately