Spirit rover on Mars. Fisheye lens view of the Mars Exploration Rover Spirit on the surface of Mars. This is a mosaic compiled from images taken by the navigation camera on the rover after it landed successfully on the planet on 4 January 2004. The lander's airbags (white, upper left) that protected the rover during landing, and the rover's solar panels (black, centre) for generating power can be seen. The golf buggy- sized Spirit rover, and an identical one called Opportunity, will study Martian rocks and look for water on the planet.