NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, has awarded Airbus a significant contract to develop and construct the GRACE-C twin spacecraft. This joint endeavor between NASA and the German Space Agency at the German Aerospace Center (DLR) marks the continuation of a partnership spanning over two decades. The mission aims to ensure continuous monitoring of Earth’s gravity field, a mission that commenced in 2002 with GRACE and has persisted with GRACE Follow-On, launched in 2018.
Over its anticipated five-year lifespan, the GRACE-C Mission (Gravity Recovery And Climate Experiment-Continuity) will extend the legacy of its predecessors by meticulously observing shifts in Earth’s groundwater, oceans, ice sheets, and land on a month-to-month basis through the measurement of changes in the planet’s gravity field.
Alain Fauré, Head of Space Systems at Airbus, expressed admiration for the mission’s objectives, highlighting the remarkable capability of satellites orbiting over 200 km apart to provide critical insights into Earth’s climate dynamics. Fauré emphasised the necessity of continuity in environmental monitoring, underscoring Airbus’s commitment to international efforts in understanding climate evolution.
The GRACE-C constellation will comprise two identical satellites flying approximately 200 km apart at an orbit altitude of 500 km with an inclination of 89 degrees. Each satellite, measuring roughly 3 x 2 x 1 meters and weighing around 600 kg, will collaborate to achieve the mission’s objectives. Launch is scheduled for late 2028 from the USA.
Similar to its predecessors, the GRACE-C mission will employ advanced technology to precisely measure minute distance changes between satellites attributable to gravity fluctuations, with unprecedented precision down to the micron. These measurements will facilitate the creation of gravity maps, enabling scientists to assess global water balance, ice sheet dynamics, ocean currents, and the impacts of climate change.
GRACE-C represents a technological advancement, incorporating upgraded avionics and the joint US-German Laser Ranging Interferometer (LRI), enhancing the precision of ranging measurements. German contributions to the mission are supported by the Federal Ministry of Economic Affairs and Climate Action as well as the Federal Ministry of Education and Research.
Airbus Defence and Space in Friedrichshafen will spearhead the design, construction, and delivery of the satellites to the launch site, providing crucial support during the Launch and Early Orbit Phase (LEOP) for NASA/JPL. Operations will be managed by the German Space Operations Center (GSOC) of DLR.
In summary, GRACE-C represents the next phase in a successful series of missions dedicated to observing Earth’s environment, cementing the collaborative efforts between NASA, DLR, and international partners in advancing scientific understanding of our planet’s dynamics.
