Solar simulator facility for the verification of space hardware performance

Abstract. The paper presents the main characteristics of the high flux solar simulator facility designed and developed at University of Padova as key enabling technology to evaluate the effectiveness of satellite hardware for missions to the inner planets of the Solar System. The designed solar simulator can reproduce the intensity and spectral distribution of the Sun's radiation up to 8 Solar constants (around 10000 Watt/m2) and the emitted flux can be directed to the viewport of a Thermal Vacuum Chamber in order to test the performance of space equipment under representative pressure and temperature conditions. Angles of incidence between 30° and 90° can be achieved using a motorised setup within the thermal chamber while different intensities of sunlight can be obtained by properly choosing the emitting lamp and regulating the electric power. After the verification of optical path alignment, a series of tests has been conducted to evaluate the flux homogeneity installing a commercial pyranometer on cartesian reference and moving the slide within the target area. A final Class A classification for the spatial non-uniformity of irradiance as for ASTM E927-19 has been achieved for the central target area. The facility has afterwards operated for validation campaign of satellite radiators in simulated orbital condition, verifying the repeatability of reproduced flux during continuous long-term operation.