The cruise stage, aeroshell and lander for the Mars Exploration Rover-1 mission and the MER-2 rover arrive at KSC's Multi-Payload Processing Facility. The same flight hardware for the MER-2 rover arrived Jan. 27; however, the MER-2 rover is scheduled to arrive at KSC in March. While at KSC, each of the two rovers, the aeroshells and the landers will undergo a full mission simulation. All of these flight elements will then be integrated together. After spin balance testing, each spacecraft will be mated to a solid propellant upper stage booster that will propel the spacecraft out of Earth orbit. Approximately 10 days before launch they will be transported to the launch pad for mating with their respective Boeing Delta II rockets. The rovers will serve as robotic geologists to seek answers about the evolution of Mars, particularly for a history of water. The rovers will be identical to each other, but will land at different regions of Mars. Launch of the MER-1 is scheduled for May 30. MER-2 will follow June 25.