Space radiation environment forecast for EGYPTSAT-2 satellite

摘要

The space environment provides an assortment of hazards whose ill effects can range from degraded performance up to catastrophic loss of a spacecraft. The radiation environment is believed to be the most significant in terms of spacecraft failures. Hence, the present work provides a radiation analysis for the EGYPTSAT-2 which is supposed to be launched in 2012 as a low Earth orbit satellite in order to assist the EGYPTSAT-2 instrument team with adequate planning decisions. AE-8, AP-8, Jet Propulsion Laboratory (JPL) model, and the cosmic ray effects in microelectronic (CREME86) code are used to estimate the fluences of the trapped electrons and protons, solar protons, and galactic cosmic protons, respectively. SHIELDOSE-2 code is used for space-shielding radiation dose calculations, and the nonionizing energy loss function is used to estimate the nonionizing dose of space radiation. Finally, the end-of-life solar cell performance is evaluated using the displacement damage dose (DDD) method. The slowed down spectra emerging from the shielding material is obtained using the Multilayered Shielding Simulation Software (MULASSIS) code. It has been found that the radiation environment will not impede the sensitivity of EGYPTSAT-2 materials over the course of the baseline mission lifetime. For 1.5 mm aluminum shielding thickness, total ionizing dose is 2.65 × 10 rads (Si) and DDD is 7.75 × 10 MeV/g(Si) for 5 years mission length, which are less than critical thresholds. Also, a flat glass of SiO2 sheet of thickness 0.5 mm is enough to resist the damage effect of the solar array cells.