FORUM will fill a critical piece of the climate puzzle. Credit: Airbus
FORUM will arrive at the National Satellite Test Facility in 2026, marking the first time a European Space Agency (ESA) Earth Explorer mission has been assembled and tested on British soil.
FORUM, short for Far-infrared Outgoing Radiation Understanding and Monitoring, will be the first satellite to observe Earth in the far-infrared spectrum. It will measure heat emissions that escape into space to provide crucial data on greenhouse gases, water vapour, and ice clouds. This groundbreaking capability will enable scientists to refine climate models and better understand how the Earth's energy system responds to global warming.
As the ninth Earth Explorer mission under ESA's Future Earth Observation Programme, FORUM continues a series of pioneering satellites that tackle fundamental questions about Earth's systems and climate processes. The Earth Explorer programme focuses on delivering cutting-edge science missions that push the boundaries of satellite observation to address pressing global challenges.
The 891kg satellite represents a significant milestone for UK space capabilities. RAL Space has signed the testing contract with prime contractor Airbus Defence and Space in the UK, whose Stevenage facility is leading the satellite's assembly. The FORUM mission builds on the UK's growing expertise in Earth observation technology and satellite manufacturing.
Scientists will use FORUM's measurements to compile high-resolution views of the Earth's greenhouse effect and atmospheric properties that current satellites cannot detect. The spacecraft's Fourier Transform Spectrometer, provided by OHB, will operate in wavelengths never before monitored from space, filling a critical gap in climate monitoring data.
Officially opened in 2024 and operated by RAL Space, the National Satellite Test Facility is the UK's first “one-stop-shop" for large satellite testing. After completing rigorous tests there – including powerful vibration tests simulating rocket launch conditions and exposure to the temperature and vacuum extremes of outer space – FORUM is scheduled to launch in 2027 on a Vega-C rocket from French Guiana. The satellite will enter a polar orbit 830km above Earth, where it will work in unison with existing European weather satellites to provide complementary observations.
Dr Sarah Beardsley, Director of STFC RAL Space, said: “We're delighted to support this landmark climate mission by providing specialist test services for FORUM at our National Satellite Test Facility. This represents a major step forward for both UK space capabilities and international climate research. Hosting the full environmental test campaign in the UK signals the trust placed in our capabilities and paves the way for future collaborations with ESA on missions that deepen our understanding of Earth's changing environment."
Harshbir Sangha, Director of Missions & Capabilities at the UK Space Agency said: "FORUM showcases our world-class capabilities in engineering and advanced manufacturing, as well as the positive impact of long-term investments in the UK's space infrastructure. By pioneering far-infrared observation from space, the mission will fill a critical gap in data about our planet, supporting UK leadership in climate science and the work of our international partners.
“This will be made possible by the important testing that prepares the satellite for space, and it is great to see this taking place in Harwell."
Justin Byrne, Head of Science Programs for Airbus said: “RAL's satellite test facilities are effectively on our UK doorstep which will enable us to accelerate the comprehensive testing of this revolutionary spacecraft."
