The rover had been on Mars for years. It had sent back a tremendous amount of data to Earth. A few months back, while navigating a rough piece of terrain, the rover's communication system was damaged, and contact with Earth was lost. When the rover was designed, scientists created a computer that would imitate the personality of a human. The communications with the rover were very similar to phone calls between two people. When the scientists were no longer able to make contact with the rover, it wandered over the Martian surface awaiting instructions. When no instructions came, it attempted to carry on a meaningful existence. Its solar batteries enabled it to function, but with no purpose. Eventually the rover, with its semi-human personality, became frustrated with the isolation and climbed a steep ridge. At the top of the precipice, it lingered for a moment, then plunged to its death.