Earth rotation-aware burn longitude guidance for targeted atmospheric entry interface of CubeSat

Introduction The rapid growth of CubeSat deployments in Low Earth Orbit (LEO) has intensified the need for reliable end-of-life disposal strategies to mitigate the accumulation of space debris. This present study proposes an Earth-rotation-aware burn longitude methodology for targeted atmospheric re-entry of CubeSat using a single finite-duration retrograde de-orbit manoeuvre. Accurate longitude-targeted atmospheric entry of CubeSat requires accounting for Earth’s rotation during the coast phase between burn execution and atmospheric interface. Methods This study presents an analytical Earth-rotation-aware burn-longitude guidance model that incorporates J 2 perturbation and atmospheric drag effects. The proposed guidance framework is integrated with a GPS-based navigation system and an Extended Kalman Filter (EKF)-assisted Attitude Determination and Control System (ADCS) for autonomous burn execution. Numerical simulations are performed for a 5.33 kg (dry mass) 4U CubeSat in circular low Earth orbits at 500 km, 600 km, and 700 km initial altitudes. Forward–only GMAT simulations independently assess the resulting re-entry trajectory without imposing a re-entry-longitude constraint, while Monte Carlo simulations evaluate the variation in the predicted re-entry longitude. Results The required burn longitudes are determined as 91.36°W, 91.47°W and 91.58°W, corresponding to Earth-rotation longitude of 11.37°, 11.50° and 11.63°, respectively, enabling accurate re-entry longitude targeting. The corresponding atmospheric-entry interface is characterized by the predicted re-entry longitude and latitude. Orbit-transfer analysis indicates that retrograde velocity increments of 108.9–162.1 m/s are sufficient to lower the perigee to the 120 km atmospheric-entry interface using less than 0.5 kg of hydrazine monopropellant. The analytical model predicts transfer times to the 120 km atmospheric entry interface ranging from 45.38 min at an initial altitude of 500 km to 46.41 min at 700 km. Discussion The proposed method provides a computationally efficient and practically implementable approach for controlled CubeSat disposal and re-entry planning in LEO.