You may be aware of Goce, the European Space Agency's gravity mapping satellite.

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The first in the series, a gravity mapper called Goce, was launched in March 2009.

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This has a tendency to heat and raise Earth's high atmosphere, buffeting Goce with stronger winds.

BBC: Goce gravity mapper surfs atmosphere

As it is, Goce probably has sufficient xenon fuel only for another 50 weeks of operations.

BBC: Goce gravity mapper surfs atmosphere

Again, in this challenge to the existing models the Goce gradients appear most pronounced in high latitude and continental regions.

BBC: Europe's Goce satellite probes Earth's gravity

Tohoku was an exceptional event and this may explain why Goce, on this occasion, was able to pick it up.

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This will necessitate Goce's ion engine having to work even harder.

BBC: Goce gravity mapper surfs atmosphere

Goran Maznov earned a soft free-kick on the edge of the area and Ilcho Naumoski fired home after Craig Gordon tipped Goce Sedloski's effort onto the post.

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