Friedrichshafen / Ottobrunn – After a successful year-long test campaign by Airbus at IABG in Ottobrunn near Munich, the twin GRACE-FO (Gravity Recovery and Climate Experiment Follow-On) satellites will soon travel to their launch site in California.
During testing, the gravity-measuring satellites, which will track the continuous movement of liquid water, ice and the solid Earth due to Earth’s changing seasons, weather and climate processes, earthquakes and even human activities, were subjected to conditions similar to those they will experience during launch and in low Earth orbit. Both satellites, each weighing 600 kilograms, will be flown to the Vandenberg Air Force Base launch site in California in December to begin final launch preparations.
The Gravity Recovery and Climate Experiment Follow-on (GRACE-FO) mission is a partnership between NASA and the German Research Centre for Geosciences (GFZ). GRACE-FO is a successor to the original GRACE mission, which began orbiting Earth on March 17, 2002. GRACE-FO will carry on the extremely successful work of its predecessor while testing a new technology designed to dramatically improve the already remarkable precision of its measurement system. The GRACE missions measure variations in gravity over Earth’s surface, producing a new map of the gravity field every 30 days. Thus, GRACE shows how the planet’s gravity differs not only from one location to another, but also from one period of time to another.
Airbus Defence and Space (Friedrichshafen/Germany) is the industrial prime contractor to build the satellites.
The project is a partnership between NASA’s Jet Propulsion Laboratory, located in Pasadena, California, together with the German Research Centre for Geosciences (GFZ, Potsdam). Both GRACE-FO research satellites will be launched into a polar orbit at an altitude of around 500 km and at a distance of 220 km apart. Both satellites will then take continuous, very precise measurements of the distance variations between each other and make monthly maps of the changes in Earth’s gravitational field, which are used to track the monthly movement of liquid water, ice and the solid Earth.
The launch of the GRACE-FO twin satellites is planned for spring 2018 on a mission planned to last at least five years.