+ NASA Homepage + Mars Home + MGS Home Summary Science Instruments Spacecraft Configurations Major Parts of the Spacecraft Attitude & Articulation Control Subsystem Command & Data Handling Subsystem Electrical Power Subsystem Propulsion Subsystem Relay Antenna Telecommunications Subsystem Spacecraft Parts The spacecraft has several major subsystems: Attitude & Articulation Control Subsystem for helping to guide the spacecraft to Mars and for keeping it oriented correctly Command & Data Handling Subsystem for storing and processing data and commands Electrical Power Subsystem for providing electricity to the spacecraft Propulsion Subsystem for correcting the spacecraft's flight path and getting into Mars orbit Relay Antenna to transmit data to and from rovers and landers on the surface of Mars (to and from Earth using Mars Global Surveyor's High Gain Antenna) Telecommunications Subsystem for radio communications between Earth and the spacecraft Last Updated: + Comments and Questions