CubeSats deployed from the ISS: development of a code to predict the orbital decay

In the last decade the number of satellites per year deployed from the International Space Station (ISS) is rapidly increasing. Despite the many pros of this strategy, the main cons is the low initial altitude of the ISS orbit which implies a shorter operational life. Indeed, a satellite deployed in that orbit, without a propulsion system, is usually meant to re-enter into the Earth atmosphere over a period of time ranging from few weeks to 3 years. This work is performed in collaboration with Nanoracks Europe which serves satellite deployment on board the ISS. The main objective of the study is to develop a software tool to predict the in-orbit behaviour of satellites deployed from the ISS, visualising the trend of the orbital elements up to the re-entry into the atmosphere and with a main focus on the altitude variation. The method, followed to examine the effect of perturbations on the satellite orbit, is a general perturbation technique, the solution of which is achieved through numerical integration; hence, the approach is semianalytical. The simulations show results for 1U, 2U and 3U CubeSats with an average relative error in the lifetime calculation of 15%. In conclusion, the work carried out could be continued by implementing some modifications to the code to strive more accurate results.