Curiosity's discovery at its landing site in the equatorial Gale Crater provides the first real ground truth for those observations.

BBC: Curiosity Mars rover beams images of ancient streambed

Since 2008, the firm's Ground Truth project has mashed together licensed data with information gathered by its own fleet of Street View cars and bicycles.

BBC: Google Maps back on iPhone after Apple software fiasco

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.

UNESCO: Combating drought in the Horn of Africa

Now the hard truth is that for decades we've been losing ground.

WHITEHOUSE: President Obama Kicks Off "Educate to Innovate"

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.

BBC: Google Maps uses Ground Truth project to battle Apple

Actually, the truth is that 4, 000 tonnes or so of uranium in the ground is a trivial amount.

FORBES: Iran Announces New Uranium Deposits: Don't Panic!

In truth, Obama was a moderate young technocrat, whose first instinct was to seek the middle ground.

NEWYORKER: Replay