A European gravity-mapping satellite orbiting about 340 miles closer to Earth than any other satellite is to be brought even lower and closer, officials say.

The Gravity Field and Steady-State Ocean Circulation Explorer, or GOCE, launched by the European Space Agency in 2009, is to have its orbit lowered by 12 miles to improve the resolution of its data-gathering instruments, ESA officials said.

Controllers have been reducing the height of the satellite's orbit by about 1,000 feet a day since August.

The move is not without its risks, as GOCE will have to fight atmospheric drag to stay aloft and maintain the stability needed to measure Earth's gravity.

But the improvement in accuracy should be worth it, the ESA said.

"The science benefit that you get from decreasing the altitude and thereby increasing the spatial resolution of the data, and also the precision of what you can measure, is quite spectacular," mission manager Rune Floberghagen told the BBC.

"We will get about a 35 percent increase in the quality of the data."

GOCE is equipped with super-sensitive instrumentation to measure the subtle variations in the pull of gravity across the surface of the Earth.