Brushing away the dust gives the robot's survey instruments a clearer view of the texture and chemistry of the underlying rock.

BBC: Curiosity Mars rover deploys its rock brush

The acquisition will allow Chevron to gain a foothold in the Marcellus shale, a giant rock formation underlying Pennsylvania, New York and other states that has become one of the most prolific sources of natural gas in the U.S. But how much equity value does this really add to the company?

FORBES: Chevron's Natural Gas Push Has Limited Upside For Stock

Even then all can be lost due to the shifting legal terrain underlying fossil collection, as in the famous case of "Sue, " the rock star of T. rex skeletons.

FORBES: Fossil Hunting