Spectral content of solar radiation on Martian surface based on Mars pathfinder

Photovoltaic arrays were used successfully to power the various instruments for the Mars Pathfinder. To identify the type of the solar cell most suitable for Mars surface missions in the future, the spectral content of Mars's solar radiation must first be determined. The response of photovoltaic cells depends on the solar cell type and the wavelengths of the incident light. The suspended dust particles of Mars's atmosphere affect the intensity and spectral content of the solar radiation reaching the planet's surface. The Pathfinder employed four bandpass filters for measuring the atmospheric optical depth during the course of the mission that lasted for about 80 sols (Martian days). The central wavelengths of these filters were 450, 670, 883, and 989 nm. This paper deals with the analysis of the optical depth of the Martian atmosphere based on the Mars Pathfinder measurements and includes 1) variation of the monochromatic optical depth with the time of the day, 2) variation of the monochromatic optical depth with sol for the duration of the mission, 3) variation of the optical depth with wavelength, 4) transmittance of the direct beam with wavelength, and 5) solar cell response on the Martian surface of the direct beam irradiance.