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Mars's Thermal Environmentextracted from Thermal Environments JPL D-8160
Perihelion Aphelion Mean ---------------------------------------------------------------- Direct Solar 717 W/sqM 493 W/sqM 589 W/sqM Albedo 0.29 0.29 0.29 (subsolar peak) Planetary IR. near subsolar 470 W/sqM 315 W/sqM 390 W/sqM polar caps 30 W/sqM 30 W/sqM 30 W/sqM The Martian planetary infrared has been derived from Mariner and Viking Orbiter spacecraft data. The distribution of Martian albedo with latitude is shown below. This albedo shows a shift in spectrum to the red in comparison with other planets and peaks at 0.7micron (versus 0.47micron for the Earth). It should be pointed out that the above environments assumes no dust storms. The presence of global dust storms would slightly increase the overall albedo (dark area albedos would increase more than bright area albedos). The increase atmosphere opacity would dampen the effective diurnal temperature range making the IR more benign.
ALBEDO DISTRIBUTION Latitude Maximum ALbedo Minimum ALbedo ------------------------------------------------------- 80 to 90 0.5 0.3 70 to 80 0.5 0.2 60 to 70 0.5 0.2 50 to 60 0.5 0.17 40 to 50 0.28 0.17 30 to 40 0.28 0.18 20 to 30 0.28 0.22 10 to 20 0.28 0.25 0 to 10 0.28 0.25 -10 ro 0 0.28 0.20 -20 to -10 0.25 0.18 -30 to -20 0.22 0.18 -40 to -30 0.22 0.18 -50 to -40 0.40 0.25 -60 to -50 0.40 0.25 -70 to -60 0.40 0.30 -80 to -70 0.40 0.40 -90 to -80 0.40 0.40
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