Crystal Dike
A UK-led climate-monitoring satellite, HydroGNSS, has entered orbit after it was launched aboard a SpaceX rocket on November 28, the UK Government confirmed in a statement on Saturday.
The spacecraft is the first mission under the European Space Agency’s (ESA) Scout programme and was designed and built by Surrey Satellite Technology Ltd (SSTL) in Guildford. The project is backed by £26 million in funding from the UK Space Agency.
According to the release titled “HydroGNSS: UK leads ESA’s first ‘Scout’ climate mission into orbit,” the satellite will monitor global water movement, including soil moisture, surface flooding, frozen ground and vegetation cover. These measurements are expected to improve weather forecasting, flood prediction, agricultural planning and long-term climate research.
HydroGNSS uses GNSS Reflectometry, a technique that captures navigation-satellite signals after they bounce off the Earth’s surface. This allows the satellite to collect data through cloud and vegetation, overcoming limitations of traditional sensors and providing a cost-effective method for environmental monitoring.
Managing Director of SSTL, Andrew Cawthorne, said the successful launch of both HydroGNSS satellites marked a major milestone for the UK space industry, noting that they represent SSTL’s 75th and 76th satellites, launched in the company’s 40th anniversary year.
The satellites will provide frequent global measurements to enhance climate models and deepen understanding of the water cycle, supporting ecosystem monitoring, agricultural decision-making and disaster response in areas affected by drought, flooding and extreme weather.
Director of Operations at the Environment Agency, Paul Clements, said the mission would significantly strengthen flood forecasting and warning capabilities in the UK, helping protect lives, property and infrastructure amid increasing climate-related risks.
HydroGNSS will complement existing international missions, including ESA’s SMOS and Biomass missions, and NASA’s SMAP satellite, as part of a wider global effort to track environmental change. The project also demonstrates how small satellites—a UK strength—can deliver high-value science at low cost.
ESA’s Director of Earth Observation Programmes, Simonetta Cheli, described the launch as a milestone for ESA’s new generation of rapid, low-cost Earth observation missions, adding that the mission will provide valuable insights into key hydrological variables shaping Earth’s water cycle.