Trajectory design for the GEO Debris Observation Satellite

The satellite and debris environment in GEO (Geostationary Satellite orbit) region is also as serious as in the LEO (Low Earth Orbit). In this respect, there has been a need for improved surveillance of objects in the GEO region. In NASDA, a conceptual study has been carried out on the on-orbit debris observation system. In this study, we had designed its trajectories in two types. One is "Near-Geostationary Satellite Orbit (NGEO)" and the other is "Fixed Apsis High Eccentricity Elliptical Recurrent Orbit (HERO)". NGEO orbit is a candidate for circular orbit of 500 km to 1000 km lower than GEO orbit. Using this orbit, whole of the GEO region could be monitored with sufficiency long observation time. The HERO orbit has high eccentricity and high inclination crossing the GEO ring at the apogee point. This orbital apsis line does not move in the orbit plane virtually because it has optimum inclination with J₂ term effect. In this paper, we will explain these 2 types of orbits.