European Space Agency (ESA) Gravity and Ocean Circulation Explorer (GOCE) mission

A handout photo received from the European Space Agency (ESA) March 31, 2011, shows a computer model created by the ESA's gravity mapping satellite, Gravity and Ocean Circulation Explorer (GOCE) mission, of how the pull of gravity varies minutely over the surface of the Earth, from deep ocean trenches to majestic mountain ranges. After just two years in orbit, ESA's GOCE satellite has gathered enough data to map Earth's gravity with unrivalled precision. The computer model called a 'geoid' is also used as a reference surface from which to map the topographical features on the planet. A precise model of Earth's geoid is crucial for deriving accurate measurements of ocean circulation, sea-level change and terrestrial ice dynamics. In addition, a better understanding of variations in the gravity field will lead to a deeper understanding of Earth's interior, such as the physics and dynamics associated with volcanic activity and earthquakes. Areas of strongest gravity are in yellow and weakest in blue.