A wide variety of missions could be enabled by extended orbital flight in extreme low Earth orbit, defined as an altitude range of 150–250 km. This study investigates the feasibility of a nanosatellite (mass $<10\mathrm{kg}$) using a propulsive, attitude control system in conjunction with a primary propulsion system to extend mission life. The primary propulsion system consists of a pair of electrospray thrusters providing a combined thrust of 0.12 mN at 1 W. Pulsed plasma thrusters are used for attitude control. The mission consists of two phases. In Phase I, a 4U CubeSat is deployed from a 414 km orbit and uses the primary propulsion system to deorbit to an initial altitude within the targeted range of $244\pm 10\mathrm{km}$. Phase I lasts 12.73 days, with the propulsion system consuming 5.6 g of propellant to deliver a $\mathrm{\Delta }V$ of 28.12 m/s. In Phase II the mission is maintained until the remaining 25.2 g of propellant is consumed. Phase II lasts for 30.27 days, corresponding to a $\mathrm{\Delta }V$ of 57.22 m/s with a mean altitude of 244 km. Using this approach, a primary mission life of 30.27 days could be achieved, compared with 3.1 days without primary propulsion.

通过在极低地球轨道（定义为 150-250 公里的高度范围）中延长轨道飞行，可以实现各种各样的任务。本研究调查了纳米卫星（质量$<10\mathrm{公斤}$) 结合主推进系统使用推进姿态控制系统来延长任务寿命。主推进系统由一对电喷雾推进器组成，在 1 W 时提供 0.12 mN 的组合推力。脉冲等离子体推进器用于姿态控制。任务包括两个阶段。在第一阶段，4U CubeSat 从 414 公里轨道部署，并使用主推进系统脱离轨道到目标范围内的初始高度$244\pm 10\mathrm{公里}$. 第一阶段持续 12.73 天，推进系统消耗 5.6 克推进剂以提供$\mathrm{\Delta }伏$28.12 m/s。在第二阶段，任务会一直持续到剩余的 25.2 克推进剂被消耗完。第二阶段持续 30.27 天，相当于$\mathrm{\Delta }伏$57.22 m/s，平均海拔 244 km。使用这种方法，可以实现 30.27 天的主要任务寿命，而没有主要推进的则为 3.1 天。