Arctic Weather Satellite paves way for constellation
The Arctic Weather Satellite Paves the Way for a Constellation of Small Satellites
The European Space Agency's (ESA) Arctic Weather Satellite has successfully completed its mission, demonstrating the feasibility of a new approach to Earth observation using small satellites. Launched in August 2024, this small prototype mission has exceeded expectations by providing high-quality data that has been assimilated into operational weather forecasts. The success of this mission has paved the way for a constellation of similar satellites, known as EPS-Sterna, which will provide frequent observations to support very short-term weather forecasts and nowcasts in the Arctic and around the world.
The Need for a Constellation of Small Satellites
The Arctic region is experiencing increasingly intense weather variability due to climate change, making it essential to have more frequent and accurate data to support weather forecasting. The concentrations of water vapor in the Arctic can change rapidly, affecting forecast accuracy. A single satellite cannot provide the necessary coverage, but a constellation of small satellites can fill this gap. The EPS-Sterna constellation will comprise six satellites, with two satellites as spares, leading to a total of twenty satellites to be built.
The Arctic Weather Satellite's Success
The Arctic Weather Satellite was designed to demonstrate the feasibility of a small satellite for Earth observation. Equipped with a cross-track scanning microwave radiometer, the satellite delivers detailed measurements of atmospheric humidity and temperature. Even though it was a prototype mission, the European Centre for Medium-Range Weather Forecasts (ECMWF) deemed its data so good that they assimilated it into operational weather forecasts. The data, along with numerous other observations, are merged with a short-range forecast that is guided by earlier measurements to produce the most accurate possible snapshot of the Earth's current state.
The EPS-Sterna Constellation
The EPS-Sterna constellation will provide global observations, with most data available within around an hour and revisit times of less than three hours for the same location on Earth. This will be a major step forward compared with current polar-orbiting satellite systems, which typically observe the same area only twice a day. The increased observation frequency will significantly enhance the monitoring of rapidly evolving weather, improving forecasts of severe events in vulnerable regions such as the Mediterranean, while also closing critical data gaps over the Arctic.
The Benefits of the EPS-Sterna Constellation
The EPS-Sterna constellation will have numerous benefits, including:
- Improved weather forecasting: The increased observation frequency will allow for more accurate and timely weather forecasts, which will be essential for mitigating the impacts of severe weather events.
- Enhanced monitoring of the Arctic: The constellation will provide critical data on the Arctic region, which is experiencing rapid climate change.
- Increased understanding of weather patterns: The EPS-Sterna constellation will provide a better understanding of weather patterns, which will be essential for improving weather forecasting and mitigating the impacts of severe weather events.
The Future of the EPS-Sterna Constellation
The EPS-Sterna constellation is expected to be launched in 2029, with the first satellites being built by the ESA. The constellation will be replenished twice during its lifetime to ensure continued delivery of data until at least 2042. The formal agreement between the ESA and Eumetsat is to be signed shortly, marking the beginning of a new era in Earth observation.
Conclusion
The Arctic Weather Satellite has successfully completed its mission, demonstrating the feasibility of a new approach to Earth observation using small satellites. The success of this mission has paved the way for a constellation of similar satellites, known as EPS-Sterna, which will provide frequent observations to support very short-term weather forecasts and nowcasts in the Arctic and around the world. The EPS-Sterna constellation will have numerous benefits, including improved weather forecasting, enhanced monitoring of the Arctic, and increased understanding of weather patterns. The future of the EPS-Sterna constellation is bright, and it is expected to be launched in 2029, marking the beginning of a new era in Earth observation.
