Space: GOCE Completes his Mission
After more than four years in orbit, mapping the Earth's gravity, ESA's GOCE mission is coming to an end. Due to run out of fuel in mid-October, the sleek satellite will begin a natural descent towards the Earth. Most of the spacecraft will burn up in the atmosphere but its re-entry will be closely monitored from the ground. GOCE -- or Gravity field and steady-state Ocean Circulation Explorer -- was the first of ESA's Earth Explorer missions and has significantly improved our understanding of the Earth's gravitational field. Courtesy Mars Underground This has given rise to a unique model of the 'geoid', which is the surface of an hypothetical global ocean in the absence of tides and currents, shaped only by gravity. It is a crucial reference for measuring ocean circulation and sea-level change, which are affected by climate change. The colours in the image represent deviations in height ( -100 m to + 100 m) from an ideal geoid. The blue colours represent low values and the reds/yellows represent high values.