超低高度衛星技術試験機「つばめ」(SLATS)の姿勢軌道制御成果

Abstract

Super Low Altitude Test Satellite (SLATS) nicknamed “TSUBAME'' was successfully launched on December 23, 2017. The purposes of SLATS are 1) Test of keeping satellite's altitude with its own ion engine against high atmospheric drag at super low altitude, 2) Data acquisition of atmospheric density and atomic oxygen, and 3) Test of optical earth observations. SLATS operation was finished on October 1, 2019. SLATS got following results in terms of the attitude and orbit control. 1) Orbit transfer from initial orbit which is 643 Χ 450km elliptic and descending node local sun time (LST) 10:30 orbit to initial super low altitude orbit which is 271.5km circle and LST 16:00 orbit using a chemical gas jet system (RCS) and an atmospheric drag for about one year, 2) Altitude keeping at 271.5, 216.8km altitude for 38days respectively and at 250, 240, 230, 181.1, 167.4km altitude for 7days respectively, 3) Guidance and longitude keeping at 271.5km/1day, 216.8km/5days and 181.1km/3 days recurrent orbits. This paper shows the on-orbit results in terms of the attitude and orbit control of SLATS.