A Jewel in ESA's Crown

摘要

Its elegant and aerodynamic design catches your eye. It is designed to fly as low as 250 km, putting great demands on its thermal and mechanical stability. It uses an ion engine to compensate constantly for atmospheric drag to keep it in orbit. This is GOCE, the 'Ferrari' of gravity field measurement satellites. One of the main problems with observing gravity from space is that the strength of Earth's gravitational attraction diminishes with altitude. The orbit of the satellite must therefore be as low as possible to observe the strongest possible gravity field signal. On the other hand, the measurement environment provided by the satellite needs to be extremely quiet and ideally free of non-gravitational forces.