Earth Observation from Elliptical Orbits with Very Low Altitude Perigee

Small Earth Observation satellites can obtain higher resolution with smaller payloads when operating at very low altitude. The life limiting effect of residual atmospheric drag can be reduced flying elliptical, low-altitude perigee orbits, with perigee right above the mission target; however, such orbits are severely affected by Earth gravitational field anisotropy and drag itself. The use of on-board electric propulsion enables this class of missions, making it possible to control and maintain orbital parameters without adding too much to the overall vehicle mass and size. This paper illustrates a possible validation mission for such a concept