1 Introduction Electrostatic thrusters (“ion engines”) are the best developed type of electric propulsion device, dating in conception to the ‘50’s,(1) and having been demonstrated in space in 1964 on a suborbital flight of the SERT I spacecraft(2). The early history

The STAR 13B incorporates the lightweight case developed for the STAR 13 with the propellant and nozzle design of the earlier TE-M-516 apogee motor. The motor case has been stretched 2.2 inches to provide for increased propellant loading. The motor has been used to adjust orbit inclination of a satellite from a Delta launch

method was developed by Raschig. Anhydrous hydrazine is a clear, colorless, hygroscopic liquid with an odor similar to that of ammonia. Anhydrous hydrazine is a strong reducing agent and a weak chemical base. Aqueous hydrazine shows both oxidizing and reducing properties. Although potential data show hydrazine

Suppose we want to move a satellite in a circular orbit to a position ∆ϑ apart in the same orbit, in a time ∆t (assumed to be several orbital times at least). The general approach is to transfer to a lower (for positive ∆ϑ ) or higher (for ∆ϑ < 0 ) nearby

The result appears to be trivial, but it is not. Notice that the “velocity increment” ∆V is actually equal to the decrease in orbital velocity. The rocket is pushing forward, but the velocity is decreasing. This is because in a r-2 force field, the kinetic energy is equal in magnitude but of the opposite sign

Lecture 1a: Mission Requirements for Space Propulsion Missions Requiring High Thrust (chemical thrusters) Planetary takeoff (launch rockets) Planetary landing (Viking, Lunar Lander…) Apogee kick (GTO-GEO transfer motors) Perigee kick (GTO to escape) Rapid maneuvering (proximity ops., spacecraft attitude control)

一、单项选择题： １．推进我国政治体制改革的重点是（） A．坚持和完善人民代表大会制度 B．坚持和完善共产党领导下的多党合作制度和多党政治协商制度 C．坚持和完善民族区域自治制度 D．依法治国 答案： D

一· 新时期党的建设的总要求和工作重点 二· 思想建设必须放在党的建设的首位 三· 组织建设是党的建设的突出环节 四· 作风建设是党的建设的重要内容

一、港、澳、台问题的由来 二、完成统一大业是中华民族的根本利益所在 三、一国两制推进祖国的和平统一 四、国两制”的伟大实践

《马克思主义哲学研究》：结合西方马克思主义哲学推进马克思主义哲学中国化研究——葛兰西哲学对马克思主义哲学中国化研究的启示（吴昕炜）