Ten years ago, ESA launched one of its most innovative satellites. GOCE spent four years measuring a fundamental force of nature: gravity. This extraordinary mission not only yielded new insights into our gravity field, but led to some amazing discoveries about our planet, from deep below the surface to high up in the atmosphere and beyond. And, this remarkable mission continues to realise new science today.
Because of factors such as the planet’s rotation, the position of mountains and ocean trenches and different densities in materials in Earth’s interior, the force of gravity at Earth’s surface varies from place to place.
Mapping these differences is important for measuring ocean circulation, sea-level change and for understanding otherwise hidden processes occurring deep inside the planet, for example.
Orbiting as close to Earth as possible, GOCE mapped these subtle variations with extreme detail and accuracy.
Just two years after it was launched, GOCE had gathered enough data to map our gravity field with unrivalled precision, resulting in the most accurate model of the ‘geoid’ – the surface of an ideal global ocean at rest.
In fact GOCE’s four years in orbit resulted in a series of gravity models, each more accurate than the last. And, importantly, yet another even more accurate model will soon be released to the public.