The ESA’s Gravity field and steady-state Ocean Circulation Explorer (GOCE), which was launched from Russia in March 2009, managed to spend 2 1/2 more years on its mission than was initially expected. During these extra years of work, it was taken to the lowest altitude orbit of any research satellite to capture the gravity data of unequalled accuracy.
On Monday, GOCE’s supply of xenon fuel was finally depleted and the ESA declared the mission over.
The work of the flight control team did not end with that, though, as the 1,100 kilogram satellite will still be orbiting for about two weeks, before its system stops working and it plunges back into the atmosphere from an altitude of 227 kilometers (139 miles).
The last part is particularly tricky, as even with all the latest technologies available, the space agency is unable to predict where parts of GOCE might fall.