The Solar Probe Plus solar array development and design

The Solar Probe Plus (SPP) spacecraft will orbit as closely as 9.5 solar radii from the sun; so close that its thermal protection shield (TPS) will reach a peak temperature of 1,400C. To work in this environment, the solar array will use pressurized water cooling and operate in the penumbra formed by the TPS at a 68° angle of incidence. Even with these mitigations, the array will be subject to extremely high intensity and temperature. This paper will summarize the array's environment, present a preliminary design, outline development plans and describe phase A test plans.