A Small Satellite Constellation for Monitoring of the Aurora

As part of the European Space Agency\u27s D3S (Distributed Space Weather Sensor System), a small satellite constellation is currently being designed by OHB Sweden which will observe space weather impacts in Earth\u27s vicinity by monitoring of the auroral oval. The primary objective of the Aurora mission is to observe the Aurora Borealis and Australis continuously and as complete as possible. The auroral emissions are the result of interactions of the Solar Wind and Coronal Mass Ejections with the Earth which drive the location and strength of electron precipitation on the ionosphere. Such observations will thereby allow the identification, characterization and nowcasting of geomagnetic storms and sub-storms. Observation of the auroral emissions is expected to enable improved and new services relevant for critical infrastructures such as communication, satellite navigation, satellite operation, aviation, transport, power network operation, and resource utilization. The core instruments of the Aurora mission are the optical and far UV wide-field imagers. Furthermore, a radiation monitor and a magnetometer are baselined as a secondary payload to monitor magnetic field dynamics and the radiation environment. The availability of additional resources for other payloads relevant for D3S is under investigation. To minimize the number of satellites, while ensuring continuous and guaranteed coverage of the auroral oval, a constellation of four satellites in MEO orbit is envisaged. Such orbit however poses significant challenges for small satellites in terms of accessibility, sustainability, and radiation dose. The heritage microsatellite platform from OHB Sweden, InnoSat (designed for LEO), will thus undergo several upgrades in terms of maneuverability, shielding, communication, and reliability. Of particular importance is the low latency requirement which may favor an Inter-Satellite Link. In a first step ESA is implementing a demonstrator mission that shall be launched in 2027 with the aim of optimizing the performance and preparing the operational satellite constellation considered for implementation in a second step. We will report about the status of the satellite design and the mission architecture