Skimsat: a small-satellite platform exploiting very low-Earth orbit (VLEO): in-orbit demonstrator mission update

Very Low Earth Orbits (VLEO) offer improved performance for payloads, and a lower radiation dose compared to LEO missions, allowing comparable performance with smaller and cheaper satellites. Skimsat is a small platform (<300kg) designed to exploit these advantages by operating at approximately 240km for up to 5 years. The in-orbit demonstrator mission (IOD) aims to demonstrate the concept and derisk the main technologies and operational concepts required for VLEO. The Skimsat IOD will utilise a gridded ion engine providing drag compensation to operate for up to 3 years in VLEO (with a propellant capacity for 5 years). Skimsat is designed to minimise drag and be aerodynamically stable—Direct Simulation Monte Carlo (DSMC) methods are used to simulate the aerodynamic performance in the denser residual atmosphere. Drag levels of 2.5mN–5mN are expected. Atomic oxygen exposure to external and internal surfaces is also simulated. This paper describes the latest progress in the analysis and design of the IOD since it was presented at the 1st International Symposium on VLEO Missions and Technologies in 2021. This activity is co-funded under Discovery, Preparation and Technology Development (DPTD) and the General Support Technology Programme (GSTP) activity run by the European Space Agency.