The Freja Science Mission

摘要: Freja*, a joint Swedish and German scientific satellite launched on October 6 1992, is designed to give high temporal/spatial resolution measurements of auroral plasma characteristics. A telemetry rate (520 kbits s-1) ≈15 Mbyte distributed board memories that the average 2 Mbits s-1 for one minute enables Freja resolve meso micro scale phenomena in 100 m range particles 1–10 electric magnetic fields. The on-board UV imager structures kilometer size with time image per s. Novel instruments capability increase spatial/temporal orders magnitudes above achieved satellites before. objective study interaction between hot magnetospheric topside atmosphere/ionosphere. This leads strong energization ionospheric an associated erosion, loss, matter from Terrestrial exosphere. orbits altitude ≈600–1750 km, thus covering lower part acceleration region. hosts processes heat energize zone, leading escape formation large density cavities.