GRACE Mission Promises improved maps of Earth gravity



Twin satellites, each the size of a sub-compact car, flying in formation around the Earth 16 times each day in a polar orbit, are set to revolutionize our knowledge about gravity on the planet.

Launched on 17 March from Russia's Plesetsk Cosmodrome, the Gravity Recovery and Climate Experiment (GRACE) promises to produce 60 gravity maps of the Earth, one each month for 5 years. Scientists estimate the maps will be 100–1,000 times more accurate than those currently used. In addition to providing basic gravity information, the mapping information will be used to study oceanography hydrology glaciology and other fields.