This image from August 2008 shows NASA's Mars Science Laboratory rover in the course of its assembly, before additions of its arm, mast, laboratory instruments and other equipment.

The six wheels are half a meter (20 inches) in diameter. The deck is 1.1 meter (3.6 feet) above the ground.

The Mars Science Laboratory spacecraft is being assembled and tested for launch in 2011.

This image was taken at NASA's Jet Propulsion Laboratory, Pasadena, Calif., which manages the Mars Science Laboratory Mission for NASA's Science Mission Directorate, Washington. JPL is a division of the California Institute of Technology.