Arctic Weather Satellite - One Year in Orbit

The European Space Agency's Arctic Weather Satellite (AWS) Proto-flight Model was successfully launched on August 16, 2024. Based on the OHB Sweden’s Innosat platform, the satellite carries a microwave sounder developed by AAC Omnisys. This paper presents the project execution, which balanced a short development schedule and tight cost boundaries, while ensuring that the mission could provide high quality meteorological data. Being a prototype for the design of the satellites to be deployed in the planned EPS-Sterna constellation, the in-orbit commissioning of AWS is crucial to validate the performance of the space segment. A key objective of the Arctic Weather Satellite mission is to demonstrate that high-quality meteorological data can be produced cost efficiently using a dedicated constellation of small satellites in low polar orbits providing frequent coverage of the polar regions to support Nowcasting and Numerical Weather Predictions (NWP), in particular of the Arctic and Antarctic regions. This is new approach for ESA and EUMETSAT in comparison to previous large-scale programs. With the increased recognition of the significance of the polar regions with respect to climate change and the increased economic and research activities occurring in the Arctic, the need for reliable weather forecast has increased. The paper provides a summary of in-orbit performance from the first year in orbit with focus on the Launch and Early Orbit Phase and Satellite In-Orbit Verification. The commissioning of the satellite platform, including required orbit adjustments and validation of the radiometer’s performance, was accomplished within a short timeframe, adhering to the project’s overall boundary conditions. AWS is designed with features to reduce operational costs of the constellation by enhancing onboard autonomy and operability. Examples of how the autonomy has performed, and what improvements have been implemented based on the operational experience gained during the commissioning, will be presented. The planned EPS-Sterna constellation will include six operational satellites distributed across three orbital planes, providing frequent coverage of polar regions to improve Weather Prediction accuracy for both the Arctic and Antarctic regions. The AWS prototype mission is funded under ESA’s Earth Watch program, with OHB Sweden as the mission's prime contractor and platform provider.