The Mountain View, California has also driven more than 5 million unique miles as part of its five-year quest (called project Ground Truth) to build more accurate maps from its own raw data rather than licensing map content from others, said Brian McClendon, head of Google maps.

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Far from being the Pentagon Papers redux, the larger truth is how closely the ground-eye view in these documents reinforces what U.S. officials were long saying: that the war wasn't going well, the Taliban were making gains, and a new and invigorated strategy was needed to combat them.

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Beyond Ground Truth, Google also aims to improve its service by mapping the interiors of more buildings - the current emphasis is on transport hubs, shopping centres, museums and business that pay for an approved photographer to visit them.

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The technology processes remote-sensing data, including data from the LANDSAT and RADAR satellites, in combination with ground truth data provided by a ground penetrating radar and other information drawn from geological, hydrogeological, geographical, hydrological and climate data and, when dealing with deep aquifers, seismological data.

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